Acidic and Basic Amino Acids Explained

Discover the chemical differences between acidic and basic amino acids. Learn about the structure and nature of amino acids, the difference between acidic vs. basic substances, the pH scale used to measure them, and why these differences matter.

This article will quickly inform you of the difference between acidic and basic amino acids. We’ll provide the definitions and explanations you seek, including what are amino acids, what makes some of them acidic and some of them basic, and why that matters when it comes to the chemistry of the human body.

Amino Acids: Essential vs. Nonessential

Amino acids are the buildings blocks of protein in your body. In short, when it comes to protein synthesis and literally building new muscle, you cannot do it without your amino acids.

Nonessential Amino Acids

Your nonessential amino acids are the amino acids your body can create on its own as a byproduct of normal functioning. There are 11 of these amino acids, and they include the following:

  • Alanine (ala)
  • Arginine (arg)
  • Asparagine (asn)
  • Aspartic acid (asp)
  • Cysteine (cys)
  • Glutamic acid (glu)
  • Glutamine (gln)
  • Glycine (gly)
  • Proline (pro)
  • Serine (ser)
  • Tyrosine (tyr)

Essential Amino Acids

Your essential amino acids are the ones you need but cannot produce yourself, and so must be gained either from your diet or via supplementation. These amino acids include the following:

  • Histidine (his)
  • Isoleucine (ile)
  • Leucine (leu)
  • Lysine (lys)
  • Methionine (met)
  • Phenylalanine (phe)
  • Threonine (thr)
  • Tryptophan (typ)
  • Valine (val)

Now that you know the amino acids we’ll be talking about, let’s move on to an illustrative example of what an amino acid’s structure looks like.

Amino Acid Structure

To understand what differentiates amino acids, you’ll have to understand their structure and what they have in common. Each amino acid is made of a central alpha carbon atom (Cα), and attached to that central atom are three molecular structures, also known as functional groups: one is a carboxyl group (-COOH), the second is an amino group (-NH2), and the third is a single hydrogen atom (H). This is the same structure of all amino acids, until the last piece of the puzzle joins the rest: the R group side chain. The R group you can think of as the Radical group, as it is different and unique on each and every amino acid, of which there are 20 main ones in the human body.

Picture it, if you will, as a group of lava lamps. Each one is made up of a light bulb in the center, a power cord, a stand, and a cap. With a long row of 20 identical lava lamps, imagine that the only thing that would make any of them unique is the color combination inside its radical glass lava vessel. Maybe one vessel has blue water and green lava, while another one has purple water with yellow lava, while yet another has blue water combined with yellow lava. With 20 different color combinations, you have enough to represent all 20 amino acids. The light bulb in the center? That is your central alpha carbon. The power cord? The carboxyl group. The supporting stand? Your amino group. And the little decorative cap on top? Your single hydrogen atom.

We illustrate it this way because it’s that glass lava vessel that not only determines what kind of amino acid you have (i.e. what color your lava lamp is), but these side chains also determine whether or not an amino acid is basic or acidic. With that structure explained, let us next generally cover acid vs. base when it comes to a chemistry standpoint.

Acid vs. Base: The Basics About Acids

In chemistry, we’re talking about molecules (which are themselves made up of atoms). A base molecule or compound is the opposite of an acid. Acids are the compounds that donate a hydrogen ion (H+) to a base, while a base compound is one that can remove a proton (H+ is a proton) from an acid. A strong base molecule can deprotonate, or take the proton, of a weaker acid such as water.

Differences between acidic and basic amino acids.

Water, Acids, and Alkalis

Hydrogen molecules are why bases and acids are often measured in pH levels (pH stands for “potential of hydrogen”) as related to pure water. The pH scale goes from 0-14. The pH of pure water is 7, precisely in the middle.

When an acid is dissolved in water, it becomes a solution with higher hydrogen ion activity than water, making it more acidic, with a pH value less than 7. When a base dissolves in water, it creates a solution with lower hydrogen activity than water, giving a pH value greater than 7. Bases that dissolve in water are called alkalis. To summarize:

  • Pure water
    • pH level: 7
    • Pure water can be swallowed by humans, is neither corrosive nor caustic, and will not burn human skin.
  • Acids
    • pH level: less than 7 (<7)
    • Named from the Latin acidus or acere, meaning sour.
    • Acids are corrosive.
    • Acids lose their acidity when combined with alkalis.
    • Examples are: citric acid (lemon juice), acetic acid (vinegar), stomach acid, and battery acid.
  • Bases
    • pH level: greater than (>7)
    • Bases that can dissolve in water are also known as alkalis, or alkaline substances.
    • Alkalis are caustic.
    • When highly concentrated, a corrosive substance will cause a chemical burn.
    • Examples are: sea water, baking soda, ammonia, garden lime, and strong lye.

To recap: the further you get from pure water on the pH scale, the more corrosive or caustic a substance becomes, and thus the more harmful to human skin (for example). On the low end of acids, you can drink orange juice, and on the low end of bases, you can swim in sea water. On the high end of acids, you have battery acid, and on the high end of bases, you have bleach, drain cleaner, and lye, which you may remember from the 1999 movie Fight Club. It occurred when Brad Pitt’s character mixed human saliva with lye on Edward Norton’s character’s skin and stated, “This is a chemical burn. […] You can use water and make it worse, or use vinegar to neutralize the burn.” Vinegar is a 2 on the pH scale, an acid that can indeed neutralize a strong base like lye (a 13 on the pH scale).

Acidic and Basic Amino Acids

Of our amino acids, which are acidic, which are base, and why does it matter? First we’ll state which is which, while quickly pointing out that the acidity of amino acids is measured with a pKa number, obtained by applying a logarithm; simply put, pKa measures acid strength, while pH measures the hydrogen content of a solution.

As a further example, for acids that means the smaller the pKa number, the more acidic the substance, and thus the lower the pH value.

Acidic Amino Acids

The two acidic amino acids are:

  • Aspartate (aspartic acid)
  • Glutamate (glutamic acid)

Acidic amino acids are those with acidic side chains, specifically containing carboxylic acid groups with pKa measurements low enough to lose protons and become negatively charged. Acidic amino acids are also by their nature hydrophilic amino acids (meaning they like water, as opposed to hydrophobic amino acids), and polar amino acids (meaning they are positively charged, as opposed to nonpolar amino acids).

Basic Amino Acids

The three basic amino acids are:

  • Arginine
  • Histidine
  • Lysine

These basic amino acids are so classified because they have basic side chains containing nitrogen, which resemble ammonia (a base). The pKa values of basic amino acids are high enough to bind protons and give them a positive charge. By nature, basic amino acids are also polar amino acids, and are also hydrophilic, just like the acidic ones.

A for Acid, B for Base, C for Conclusion

In conclusion and to summarize: the difference between acidic and basic amino acids is the same as between any acid and base in chemistry and chemical substances. Their similarities still include being polar amino acids, as well as hydrophilic amino acids, and, of course, the biggest thing they have in common is that they’re all still amino acids, with the same basic structure.

Though some are essential and some nonessential, the reason amino acids matter, and the reason that all these tiny permutations matter, is because without each of them working together, our health and well-being would fail. We at Amino Co. have developed amino acid supplements specifically because we understand their vital importance to human life. The chemistry behind each person’s daily concert of amino acids is the science that drives our passion.

When Is the Best Time to Take Protein?

The best time to take protein supplements depends on your activity level, your personal goals, and the types of workouts you engage in. This article will provide you with specific, scientifically backed recommendations, and the reasoning behind that advice.

When taking protein supplements, people often wonder when exactly is the best time of day to consume them. Pre-workout? Post-workout? Is it okay to drink a protein shake before bed? Protein supplements can help people lose weight, build muscle, and recover from tissue damage due to injury or surgery. Because they’re so effective, most people want to be sure they’re utilizing protein the right way. So when is the best time to take protein? Short answer is: that depends on your health goals and the kinds of workouts you’re doing. For the longer answer and more detail, read on.

The Different Types of Protein Supplements

Protein is a source of energy for the body, essential for muscle growth, repairing damaged tissue, and preventing certain infections and diseases. Normal dietary protein comes from foods like meats, eggs, fish, dairy, grains, legumes, and seeds. Though animal products contain the most amount of protein, vegetables are sources of protein too, a fact well-known by those living a vegetarian or vegan lifestyle. Of the most popular protein powders on the market in fact, a significant portion are plant-based.

Plant-based proteins include:

  • Soy protein containing all nine essential amino acids.
  • Rice protein, which is lower in the essential amino acid lysine.
  • Pea protein, which has lower levels of the essential amino acid methionine and nonessential amino acid cysteine.
  • Hemp protein, which is low in lysine but high in fiber, and omega-3 and omega-6 fatty acids, both of which are essential, meaning your body can’t make them on its own, and needs to gain them from the foods you eat.

Dairy-based proteins include:

  • Whey protein, which is absorbed relatively quickly and contains all nine essential amino acids.
  • Casein protein from milk curds, also containing the essential amino acids, and with a slower digestion rate than whey (which is why people often take casein before they sleep, so it will digest throughout the night… more on that timing below).

Animal-based proteins include:

  • Egg protein powder made from pure egg white protein.
  • Creatine, which is not found in plants but can be synthetically created. Though it is an animal protein, depending on its origin source, it may nevertheless be possible for vegans to use creatine as a supplement.

These are among the most commonly known protein powders available to buy, but we here at the Amino Co. have also developed an essential amino acid (EAA) blend that isn’t lacking or low on any of the amino acids required for protein synthesis and new muscle growth. It also blends free-form amino acids with whey protein and creatine, a nonessential protein that nevertheless has great value as a supplement. These forms of protein are used to help those who want to build muscle rapidly, and can even benefit those with muscle, neurological, or neuromuscular diseases.

The Varied Uses of Protein Supplementation

From muscle building to weight loss, here’s a quick look at all that supplemental protein can do to benefit your body.

Exercise Performance and Recovery

Added protein has been shown to increase endurance during training and workouts, as well as reduce soreness and speed up post-workout recovery. The timing of your protein intake matters here, whether you’re eating high-protein foods or taking supplements. Read on to learn about workout-specific timing recommendations.

Muscle Building

Muscles can only be built when you have the proper amount of amino acids for protein synthesis, and when you’re consuming more protein than your body breaks down during workouts. Taking a protein supplement, especially one that contains all the necessary EAAs for muscle growth, can make a huge difference. Finding the right anabolic window, the period of time when the protein you take in will go directly to your muscles, is something the International Society of Sports Nutrition has done extensive research on, and we, too, will provide specific scientific reasoning below.

Muscle Loss Prevention

Muscle mass is lost not only during intensive workouts, but also naturally as we age. Each decade you live after the age of 30 brings with it a higher risk of losing muscle (anywhere between 3-8% per decade). Proper protein intake is not only valuable to athletes, bodybuilders, and anyone who works out regularly, but it’s also important for each and every one of us as we age. Most Americans reserve their protein more for dinner than breakfast (3 times the amount on average is the difference between the two meals), and could use a supplemental boost of protein first thing in the morning to shore up their protein stores and help prevent the loss of muscle mass due to aging.

Fat Loss Facilitation

Protein is filling enough to help curb hunger pangs and chemically contributes to appetite suppression by reducing the “hunger hormone” ghrelin. A high-protein diet raises your metabolism and increases levels of appetite-reducing hormones like peptide YY (PYY) and glucagon-like peptide-1 (GLP-1). More satiety means fewer calories consumed throughout the day, which quickly leads to safe, maintainable weight loss and the reduction of dangerous body fat.

The Enduring Power of Protein

Popular because they’re convenient and effective, protein powders and supplements are here to stay and can offer you a wide variety of options, from self-mix formulas and powders to ready-to-drink protein shakes. If you’ve got your preferred protein supplement ready to go, then it’s time to wonder: when should you drink protein?

The Best Time to Take Protein Depending on Your Workout

Depending on your goals and activities, there are recommended times to take protein for the greatest effectiveness for your energy levels and muscle-building needs. Here are specific recommendations based on different types of workout activity.

The best time to take protein supplements.

Aerobic/Cardiovascular Exercise

Best time to take protein: Pre-workout and post-workout

The amino acid leucine is one of the three branched-chain amino acids (BCAAs), and it promotes muscle recovery after workouts. Not only that, it activates protein synthesis, prompting new muscle to be built. One might think that due to leucine’s ability to boost endurance and stamina, one should take a BCAA supplement before a workout, but the science contradicts that idea. Not only are BCAAs only three of the nine essential amino acids needed to construct new muscle, leucine and the other BCAAs (isoleucine and valine) experience oxidative degradation during aerobic activity.

BCAAs are Insufficient Pre-Workout

Adding these limited amino acids before your workout, especially in the unbalanced form of BCAAs instead of a complete EAA formula, means that a greater percentage will be oxidized and used for energy instead of muscle building. Your body does not want to be out of balance, so a sudden overabundance of a few amino acids will cause the body to clean up and reduce them in order to maintain equilibrium.

Rather than risk burning off the protein you put in because your body is only looking for energy sources, it’s better to take a full measure of EAAs within the hour after your aerobic workout, when your body is looking for supplies to rebuild. Leucine will be there to prompt muscle protein synthesis, and the rest of the essential amino acids will all be included in the ideal ratio for generating new muscle growth.

EAAs are Effective Pre- and Post-Workout

That being said, taking a complete amino acid protein supplement before an aerobic cardiovascular workout (like a high-intensity interval training or HIIT class), not only provides the necessary ingredients for muscle building, but also helps fight fatigue in a way that only taking BCAAs can’t, by fueling your body with the amino acids that help produce dopamine and serotonin in the brain.

Whether you’re walking, cycling, running stairs, or jumping rope, start by taking your EAA supplement 30 minutes before your workout session. The biggest benefit comes when you take your EAA supplement within an hour after your workout, when your blood flow is strong and active. Not only will the amino acids rush in to replace damaged muscle fibers with new muscle, EAAs can also help calm unnecessary inflammation. That will help quicken your recovery, allowing you to feel only the good side effects of working out, like increased energy and light euphoria, instead of soreness and fatigue.

Resistance Exercise

Best time to take protein: Pre-workout, during, and post-workout

Research has shown that EAAs given 30 minutes before a resistance exercise workout prompt muscle protein synthesis much more effectively than consuming EAAs afterwards does. Taking a protein supplement before this type of workout helps prevent the breakdown of muscle protein during the activity, and also increases blood flow to the muscles, thus getting the amino acids quickly into the muscle where they’re needed.

Consuming EAAs after a resistance workout is not harmful by any means, as that method, too, will prompt the stimulation of muscle protein synthesis, but it’s not ideal to leave the consumption of EAAs until after your resistance training is complete. Our recommendation is to first and foremost take a complete protein supplement before a resistance workout, and if possible take them throughout and/or after as well to get the most benefit.

Bodybuilding

Best time to take protein: Pre- and post-workout, and also before bed.

Immediately before and after a weight-lifting workout, we recommend that you take 15 grams of EAAs each. An EAA supplement has been shown to have a faster effect on muscle protein synthesis than either whey or casein protein alone. However, our Amino Co. blend of free-form EAAs with whey and creatine support ensures that you get a fast dose of EAAs and that the EAAs from whey will digest more slowly as you work out, offering a steady supply to help prevent muscle breakdown. Creatine helps prevent catabolism by supplying faster energy than your body can naturally generate from muscle cell mitochondria. This means more energy for more reps, which ultimately means more work put in and more muscle gained.

An hour after your post-workout dose of EAAs, we recommend another 15-gram dose. On off days, continue taking these same doses, measured between meals instead of surrounding your workout. Lastly, it’s also recommended you take another 15-gram dose before bed to keep your muscles fed as you sleep and to help prevent muscle breakdown as much as possible. You work hard to gain your muscles, and we encourage you to protect those gains at every opportunity. Set your alarm to take one more dose around 4 am if you know you won’t have a problem falling back to sleep, that way your muscles never go hungry for fuel.

It should be noted here that bodybuilders aren’t the only ones who benefit from taking extra protein before bed. One study of 16 elderly men showed that those who consumed casein protein (which digests slowly) before bed had increased muscle growth over those who took a placebo, despite being less active individuals. When you’re sleeping, it’s the protein that counts, and not the activity.

Is There Any Downside to Taking Protein Supplements?

The majority of scientific studies into how our bodies process high amounts of protein show that you can safely consume plenty of protein without risk of harmful side effects. Unless your doctor advises against protein supplements or you have a known kidney issue like rhabdomyolysis, there is no need to worry about excessive protein intake; merely take your products as recommended and spread them throughout your day.

Timing Is Everything

At the end of the day, it’s true that people who work out need more protein, but even those with a less active lifestyle benefit from consuming extra protein for strength, for maintaining healthy weight levels, and for preventing the loss of muscle mass we all experience as we age.

Make a protein shake for breakfast, have another to curb your appetite between meals, and make another as a beneficial treat before bed. Know that the more regularly you take in balanced forms of protein like Amino Co.’s complete EAA blend, the more good you can do for your body. Whether you’re working out or not, upping your daily protein intake is safe and smart. Bulk up, slim down, and stay strong with protein!

What are Amino Acid Functional Groups?

What is an amino acid functional group? This article will answer that question with information on amino acid classification and how proteins (and possibly all life on Earth) are formed.

What are Amino Acid Functional Groups?

So you’ve heard of amino acid functional groups and you want to understand them better. This article will help to clarify the structure of amino acids, their functional groups, and what it all has to do with the creation of protein.

Some Basic Reference Definitions

Below are the names of the 20 common amino acids in the body, nine of which are essential amino acids, meaning humans must eat or otherwise consume them to get what we need to function. The essential aminos are designated with an asterisk (*). There are their names, their three-letter codes, their one-letter codes (as used in drawing models of molecular bonds), plus their bond type and properties. Polar vs. nonpolar bond types refers to their covalent bonds. We will start with those definitions for the bond type category—get ready for some high school clique metaphors to help you visualize all this organic chemistry.

Covalent Bonds

Covalent bonds form the base of the chemical reactions between atoms of different elements. The bonds form in only one way: when an electron becomes shared by two elements. That creates the connection that then results in a new substance. Covalent bonds can exist as polar or nonpolar compounds, and all bonds that are polar or nonpolar in nature are by definition covalent.

To visualize: think of these bonds like the bonds of friendship. Two students (atoms) come close to one another and share their lunch (electrons). This sharing means there is a bond of friendship (the covalent bond). Whereas before they had been two separate elements, strangers, now a new substance has formed: a friendship.

Polar Bonds

Polar bonds are bonds where the electrons are not shared equally between two atoms. These types of bonds are what designates polar molecules from nonpolar ones. This occurs when the two atoms bonding are from two different elements; atoms from the same element do not form polar bonds.

Just as bigger planets can hold bigger moons in their orbits, so it is with atoms: they pull electrons to the best of their ability, but when they come into the orbit of a better puller (a bigger planet), that atom will pull more electrons into its orbit (and steal the lesser planet’s moons).

When two atoms of the same element meet, neither is stronger than the other, and thus neither one is more attractive than the other regarding electrons, and so neither side exhibits the polar pull, and the bond is considered nonpolar. The negative charge end of the bond is the more attractive atom, because it can draw more negative (-) electrons.

To put this back into the context of our high school friends, let’s say the two atoms meeting and bonding are a vivacious theater student and a more reserved math student. In sharing lunch, somehow the theater student always gets more to eat because the math student is so transfixed and feels the need to be overly generous. This is true whenever the theater student meets someone with less personal magnetism, which means the theater student gets an overabundance of food (electrons), which is negative because the increased calories may cause the theater student to gain weight, or get a bad complexion from eating too much processed lunch food. Eventually the theater student will fill up to the brim with extra food, and won’t be able to accept any more.

Nonpolar Bonds

A nonpolar bond is formed when two atoms from the same element meet and share electrons equally and evenly with one another. Neither atom is a better electron puller than the other, and so there is no one side more polar than the other.

In our friendship metaphor, this is a bond between two theater students, or two math students, who pool all of their lunch food together in the middle of the table, and pull from the pile equally and in unison.

Hydrophobic vs. Hydrophilic

For the properties category, hydrophobic and hydrophilic refer to molecules and their reactions to water. Molecules that repel water, or are phobic of hydration, are hydrophobic. The molecules that can form an ionic or hydrogen bond with a water molecule are hydrophilic, they have a philia for water, they like the feel of it.

If atoms are students once again, the hydrophilic ones are either on the swim team itself, or part of a group that likes to swim and heads out to the beach or the lake every weekend. The hydrophobic ones either can’t swim or simply do not like it. Hydrophobic students will tell you that their friends and the community pool go together like oil and water: they don’t mix.

Your Amino Acids: Names and Designations

Amino-acid name: Alanine Amino-acid name: Arginine
Three-letter code: Ala

One-letter code: A

Bond type: Nonpolar

Properties: Hydrophobic

Three-letter code: Arg

One-letter code: R

Bond type: Polar, positively charged

Properties: Hydrophilic

Amino-acid name: Asparagine Amino-acid name: Aspartate
Three-letter code: Asn

One-letter code: N

Bond type: Polar, no charge

Properties: Hydrophilic

Three-letter code: Asp

One-letter code: D

Bond type: Polar, negatively charged

Properties: Hydrophilic

Amino-acid name: Cysteine Amino-acid name: Glutamate
Three-letter code: Cys

One-letter code: C

Bond type: Nonpolar, no charge

Properties: Hydrophilic

Three-letter code: Glu

One-letter code: E

Bond type: Polar, negatively charged

Properties: Hydrophilic

Amino-acid name: Glutamine Amino-acid name: Glycine
Three-letter code: Gln

One-letter code: Q

Bond type: Polar, no charge

Properties: Hydrophilic

Three-letter code: Gly

One-letter code: G

Bond type: Nonpolar, no charge

Properties: Hydrophilic

Amino-acid name: Histidine* Amino-acid name: Isoleucine*
Three-letter code: His

One-letter code: H

Bond type: Polar, positively charged

Properties: Hydrophilic

Three-letter code: Ile

One-letter code: I

Bond type: Nonpolar

Properties: Hydrophobic

Amino-acid name: Leucine* Amino-acid name: Lysine*
Three-letter code: Leu

One-letter code: L

Bond type: Nonpolar

Properties: Hydrophobic

Three-letter code: Lys

One-letter code: K

Bond type: Polar, positively charged

Properties: Hydrophilic

Amino-acid name: Methionine* Amino-acid name: Phenylalanine
Three-letter code: Met

One-letter code: M

Bond type: Nonpolar

Properties: Hydrophobic

Three-letter code: Phe

One-letter code: F

Bond type: Nonpolar

Properties: Hydrophobic

Amino-acid name: Proline Amino-acid name: Serine
Three-letter code: Pro

One-letter code: P

Bond type: Nonpolar

Properties: Hydrophobic

Three-letter code: Ser

One-letter code: S

Bond type: Polar, no charge

Properties: Hydrophilic

Amino-acid name: Threonine* Amino-acid name: Tryptophan*
Three-letter code: Thr

One-letter code: T

Bond type: Polar, no charge

Properties: Hydrophilic

Three-letter code: Trp

One-letter code: W

Bond type: Nonpolar, no charge

Properties: Hydrophobic

Amino-acid name: Tyrosine Amino-acid name: Valine*
Three-letter code: Tyr

One-letter code: Y

Bond type: Polar, no charge
Properties: Hydrophilic

Three-letter code: Val

One-letter code: V

Bond type: Nonpolar

Properties: Hydrophobic

It’s a lot of information, to be sure, but it’s provided as a reference point to help facilitate the following explanations.

What Are Amino Acid Functional Groups?

Amino acids are all made up of groups of atoms, and the functional groups are the important ones in each amino, it’s what makes them different and unique, deciding whether the amino overall is polar or nonpolar, acidic or basic.

Each of the above standard 20 aminos have one hydrogen atom, and two groups attached to its alpha carbon atom: an amino or amine group (~NH3+) and a carboxyl group (~COOH). They are each then distinguished from other types of amino acids by their third attached functional group: side chains referred to as R groups. When you ask what are amino acid functional groups, here they are, with the R group being the one with the most diversity. When you think of R groups, think R for radical, as it’s the variable part that makes each amino acid different from the rest.

What is the amino acid functional group?

About R Groups

Of the 20 standard amino acids that make up the building blocks of protein:

  • 6 of them have hydrocarbon R groups
  • 7 of them have neutral R groups
  • 6 of them have acid or base R groups

The simplest of the amino acids is glycine, which has just one hydrogen atom in the position of the side chain group (no R group at all, just an attached loner).

Some Quite Interesting Relevant Facts

  • In chemistry, organic compounds are generally thought of as any chemical compound that contains carbon, which includes amino acids.
  • All amino acids are soluble in an aqueous solution (water), even the hydrophobic ones (counterintuitive but true).
  • All naturally occurring amino acids are in the L-form; L for levorotatory, referring to the way you’d turn the amino acid to read the order of its attached groups (the opposite of is dextrorotatory or D-form).
  • As you can see in the above list, 50% of the amino acids have nonpolar side chains. The other half is designated polar, five of which have side chains that are not only polar, but charged.
  • Because the carboxyl group is an acid, it can form peptide bonds with the base amino groups of other amino acids, causing chemical reactions that create polypeptide chains and amino acid residues.
  • When two amino acids react and form a peptide bond, and that process goes on to be repeated, many amino acids may string together, which forms a protein structure.
  • This protein synthesis (though a little more complicated than just linking acid to base over and over again like links of a chain) is among the most fundamental of biological processes, an invaluable component of every cell. Proteins make our nails and hair, protein builds and repairs our tissues, protein is needed to make our hormones, our enzymes, and many other chemicals in the human body.
  • In 1953, Stanley Miller and Harold Urey conducted a simulation, to test a hypothesis about how life originally formed on Earth. They built a closed system that contained a heated pool of water under a mixture of gases that were thought to be present in the early atmosphere of Earth. They delivered an electric current to simulate lightning, and after a week analyzed the contents of the liquid pool. In there they discovered that several organic amino acids had spontaneously formed from inorganic raw materials. This leant support to the theory that the first life on Earth arose out of the primordial ooze through naturally occurring chemical reactions like a little flash of lightning.

Conclusion

The functional or R groups of amino acids are the groups that define the chemistry of proteins. They are the basis on which amino acids are classified, and according to the Miller-Urey experiment, possibly the start of all organic life on Earth. Not only is “What are amino acid functional groups?” a stimulating question to ask, but the answer to that question comes awfully close to revealing the true answers behind life, the universe, and…well…everything.

BCAA vs. Creatine: What You Need to Know

BCAA vs. creatine: a comprehensive look to help you decide which you should choose, or whether you’d rather utilize a product that combines the two supplements for better energy, muscle strength, and protein synthesis.

If you spend enough time in the gym, you will eventually run across this question: BCAA vs. creatine, which supplement do you prefer? Before you can answer that question, you’ll need the information behind both BCAAs and creatine: what are they? What are the upsides and downsides to each? How can they help build muscle? Can they both be taken together? You’ll find the answers to all of those questions here, plus learn about the one ultimate supplement that perfectly marries the two together, so you never have to compromise for imbalance in your muscle-building nutrients.

BCAA vs. creatine: a comprehensive look.

What Is BCAA? What Is Creatine?

We’ll start with the definitions, and then move on to the differences between these two supplement options.

BCAA: Branched-Chain Amino Acids

A BCAA supplement is made up of branched-chain amino acids, specifically the three amino acids leucine, isoleucine, and valine. There are a total of nine essential amino acids, essential because you must eat or otherwise consume them to get them (other amino acids are produced in-house by your body). Leucine, valine, and isoleucine are essential amino acids.

“Branched-chain” refers to the molecular structure of these three specific amino acids. The chemical bonds branch off of the main structure.

Studies have shown that BCAAs help reduce muscle damage and soreness in post-workout recovery.

While it’s possible to get a sufficient amount of the BCAAs from your diet, for those who work out intensively, and/or for those on specific diets aimed to lose weight, it might be difficult to get the right amino acid balance, which is why some will chose a BCAA supplement in the hope that it will round out their nutrients. However, it should be noted here that muscle synthesis cannot take place without all nine essential amino acids, so a complete essential amino acid (EAA) supplement is preferable to a BCAA one—you cannot build muscle with only a third of the necessary ingredients.

To cut calories without having a negative impact on protein intake for muscle mass is important, and BCAAs are often taken to try to ensure there’s no interruption to protein synthesis while dieting. Even if weight loss isn’t your goal, the BCAAs gained from taking a complete EAA supplement might still help in that department by contributing to appetite control.

BCAAs have similar benefits to a whey protein shake, but with fewer calories. Moreover, the amino acid leucine is one of the two specifically ketogenic amino acids, another way that BCAA supplements contribute to fat loss (the ketogenic diet is all about burning off fat, and doing it both quickly and safely).

BCAA supplements are perhaps best suited for CrossFitters, bodybuilders, or rowers, but again, they are only a third of the essential amino acids, all of which are necessary for muscle building.

BCAA Quick Facts

  • BCAAs provide three of the nine essential amino acid building blocks of muscle tissue.
  • BCAAs help protect lean muscle and guard against muscle wasting.
  • BCAA supplements are a source of longer-term energy, and can help reduce exercise fatigue.
  • BCAAs help promote fat loss via appetite suppression and increased metabolism for burning calories.
  • BCAA supplements provide higher strength gains than whey protein does.
  • There are no harmful side effects reported from BCAA supplementation.

Creatine: The Energy Protein

Creatine is creatine monohydrate, the protein found in animal sources of meat like fish, poultry, pork, and red meat. Creatine contains two different amino acids, arginine and methionine, of which methionine is essential.

Unlike the weight-loss potential in BCAA supplements, taking creatine can lead to initial weight gain, as it causes some water retention in the muscles. Likewise, if you’re not drinking enough water while taking creatine, cramping can occur, meaning it’s more important than ever to stay hydrated while working out.

Researchers have stated that creatine might help lessen the effects of osteoarthritis, slowing the loss of bone mass as you age. Another unique benefit of creatine is its ability to deliver the rapid energy that is needed during fast muscle contractions (when sprinting, for example). That means creatine gives you longer endurance, which means more reps, which means more muscle growth. This is why creatine is best suggested for powerlifters or sprinters, and why it’s a part of our unique EAA blend (see below for further details).

Creatine Quick Facts

  • Creatine breaks down into phosphocreatine (CP), which provides rapid energy for muscle contractions.
  • Creatine causes the release of the anabolic hormone IGF-1, used in promoting muscle growth.
  • Creatine is a quick source of muscle energy, allowing for more reps.
  • Creatine use aids long-term bone strength for weight trainers.
  • Creatine increases strength during resistance training by up to 20%.
  • Some water retention and cramping is reported with the use of creatine, but the effects are short term.

BCAA vs. Creatine: Which Should You Use?

If you’re here to make a choice, now’s the time to review your fitness goals and how each of these products might influence them. Research suggests that BCAAs help to increase muscle mass for those doing resistance training. If your diet is low on protein intake, say if you’re vegetarian or vegan, BCAA supplements are a great way to promote muscle protein synthesis, but remember that they are also only a partial supply of the amino acids you need for muscle building.

Likewise, a study also showed that muscle strength increased up to 8% for those using a creatine supplement while resistance training. Creatine can provide rapid energy when the usual muscle cell energy supply of adenosine triphosphate (ATP) is slow to regenerate, and it goes a long way towards the kind of strength building and increase to muscular force that might be preferred by powerlifters.

Both supplements aid muscle recovery, both contain at least one essential amino acid, both help drive protein synthesis, both of them are good to take as pre-workout supplements for their benefits, and honestly, unless you have a specific reason to not take one of them, you may be thinking that you want to take both. Well good news for you then, because you can! In fact, we recommend that you do.

BCAA and Creatine Together

You may have noticed that there was no overlap between the amino acids from BCAA supplements and creatine supplements, which means taking both will not overdose you on any one amino acid. Rather than think of them as enemies in some competition for supplement supremacy, BCAAs and creatine can be two valuable players on the same team: your team. Nothing bad will happen to you if you combine them (they’re not baking soda and vinegar in a third grader’s science fair volcano or anything), and since they both aid sports performance, boost muscle building, help with fat loss, and ease muscle recovery, when taken together you may see improved results in all of those categories.

However, if you’re after a full roster of the essential amino acids, there are amino acid supplements that include all three BCAAs, plus the other muscle-building EAAs. Whether you’re looking into supplementation because you’re lifting weights or attempting to lose body fat or both, a protein powder with only partial, unbalanced amounts of amino acids just won’t do the trick.

A Complete EAA Blend

When it comes to muscle-building supplements, our blended EAA formula not only contains eight of the nine essential amino acids, including the BCAAs, but it also supplies them with the energy of creatine and the steady amino acid digestion that comes from whey protein supplements (derived from milk).

This supplement is scientifically proven to increase human muscle growth and can help prevent muscle breakdown in the elderly. It was also designed to contain the exact ratio of amino acids needed to build muscles without overtaxing your body with excessive or unnecessary amounts of any one.

When building muscle, you don’t want to show up with a partial supply of the building blocks of protein. Instead, you want a comprehensive EAA supplement that helps all the work you do weight training at the gym to pay off. Instead of a dose of BCAAs here or a dash of creatine there, we recommend you get the most out of all of the above with our combination of EAAs with creatine and whey protein support. If the question is BCAA vs. creatine, the real answer is the Amino Company’s blends: for balance, for building, for the best of both worlds and more.

L- vs. D-Amino Acids

The difference between L- vs. D-amino acids: explore the structure of these important building blocks of human life, their definitions, their similarities, their distinctions, and their uses within the body.

Of the 20 common amino acids in the human body that build our proteins, each of them (except for glycine) occur in two isomeric forms: L-forms and D-forms. This means that the same components of the molecules can be arranged in two different orders, a tad like how a palindrome is the same word backwards as forwards (like “radar” and “kayak”). Actually with L- vs. D-amino acids, it’s more like the playful term for a word that backwards becomes a different word, a “Semordnilap” (which is “palindromes” spelled backwards). As Oprah Winfrey named her company Harpo Studios, or the town of Retsof, New York, was named for salt mine owner William Foster. Wolf vs. flow, room vs. moor, star vs. rats: the same letters, arranged exactly backwards, that then come to hold a whole new meaning. That is the basic difference between L- and D-form amino acids. The rest of this article will provide more detail and context.

What Do the L and the D Stand For?

It’s easy to assume that if something is called L-form, that must mean it’s in the form of an L, like a sectional sofa, or that D-form would refer to a half-moon shape, like a semi-circular booth in a restaurant, but that’s not what those letters stand for here. In this context, the L and the D are referring to the order the side chain structures attach to an amino acid’s central carbon atom (also known as the chiral carbon or alpha carbon). Those groups are: a single hydrogen atom (H); a carboxyl group (or COOH group); an amine group (or NH2 group); and the distinguishing R group which mostly differentiates one amino acid from another.

Picture a pair of pinwheels with four color petals (the four functional groups) attached to the centers (the alpha carbon or chiral molecules). The L-form’s colors follow the alphabet and go blue, green, red, yellow if your eyes read it like a clock; your eyes read clockwise, while the wheel spins counterclockwise. The D-form goes the opposite way: to read it in the order of blue, green, red, then yellow, D-form will have to spin clockwise, while you read it backwards, eyes traveling in the counterclockwise direction.

“L” Stands for “Levorotation”

In order for your eyes to read the amino acid correctly (in alphabetical color order) the molecule itself must rotate counterclockwise, or to the left. Levorotation refers specifically to that counterclockwise rotation.

“D” Stands for “Dextrorotation”

In order for your eyes to read the amino acid in alphabetical color order, the molecule must spin clockwise, or to the right. The prefix of dextrorotation comes from the Latin, dextro, meaning “to the right.” Your right hand is your dexterous one, and the left hand in the Latin would be your sinister one (many apologies to the left-handed among us; like right-handed writing desks and scissors weren’t enough, you are also designated sinister as well).

How to Remember Which Is Which

If you know you’re not going to remember the Latin, just remember this:

  • L stands for left-moving: The molecule rotates left so you can read its structure forward, towards the right.
  • D stands for your dextrous right hand: The molecule spins right so that you’re reading its structure counterclockwise, backwards towards the left.

L- vs. D-Amino Acids: What Do They Do?

This section will attempt to clarify the properties of L- and D-form amino acids, what makes them different, and what they have in common.

The difference between L- vs. D-amino acids.

L-Amino Acids

L-amino acids are the molecules used to produce proteins in the human body and are divided into nonessential amino acids and essential amino acids (which we must get from consuming our food). In fact, L-amino acids occur in all proteins made by animals (including humans), plants, bacteria, and fungi. They serve as both hormones and enzymes, regulating the functions in the body. L-amino acids are also the ones that can be produced by lightning reactions, possibly the origin of the organic compounds of life on Earth, and the building blocks of our proteins.

D-Amino Acids

The D-forms of amino acids are mirror images of the L-form amino acids. D-amino acids are not incorporated into proteins; however, D-serine acts as a neurotransmitter in the brain. Some D-amino acids can be found in bacterial cell walls, but again, not in bacterial proteins.

The Similarity

They are each one of the two forms that amino acids can take in nature. Normal chemical synthesis of amino acids always creates a racemic mixture, which is a mixture of equal parts L- and D-amino acids. They are mirror images of one another, and each contain a central carbon atom, a hydrogen atom, a carboxylic acid group, an amine group, and an R group carbon chain. They are like identical twins born to be the reverse of one another, as in this real case of twin boys who were nearly conjoined, but instead were born with their livers, hearts, and spleens on opposite corresponding sides of their bodies. That means one twin has a condition called dextrocardia, where his heart points towards the dextrous or right side of his body, instead of the left side. They are identical, but with opposite features, as in one of the boys is right-handed, and the other, left-handed. (Interestingly enough, there is a chance that as many as a quarter of all identical twins could be mirror twins.)

The Difference

The main difference between these two formations is the location of the amine group in their structure, which designates how the amino acid will be used. L-amino acids are used in protein synthesis, while D-amino acids are not. L-aminos rotate counterclockwise or left in a process known as levorotation, while D-amino acids rotate clockwise to the right, in what’s known as dextrorotation. Usage-wise, L-amino acids are used to produce proteins, making them vitally important to our healthy functioning, while D-amino acids are found instead in the cell walls of bacteria.

Conclusion: L vs. D

Hopefully the explanation and comparison of the L- and D-form amino acids has enlightened the subject and shown you their similarities and their differences: less like dexter vs. sinister, and more like brother-to-brother twins.

What Are Hydrophilic Amino Acids?

You may have run across the term hydrophilic amino acids and wondered what it meant and what do they do? Hope you feel like brushing up on some basic organic chemistry, because this article’s aim is to shed some light on the subject.

You may have run across this term and wondered what it meant—what are hydrophilic amino acids and what do they do? Hope you feel like brushing up on some basic organic chemistry, because this article’s aim is to shed some light on the subject, and give you a quick chemistry refresher course on these important structures and molecules in our bodies.

Definitions

We’ll start with the basics: polar molecules, hydrophilic vs. hydrophobic molecules, and the amino acids.

Polar Molecules

Polar molecules are what form when two atoms from different elements come together to make an uneven compound. One atom will be stronger and will pull negative electrons away from the other atom. That makes the molecule polar: one end is positive, with fewer electrons, and the other end is negative, hogging as many electrons as possible.

Water is a polar molecule because H2O means there’s two hydrogen atoms that can then form hydrogen bonds attached to the one stronger oxygen atom: oxygen has six electrons of its own, but it can hold onto eight, and so when two unsuspecting hydrogen atoms come along, each of them having just one electron to call their own, oxygen gathers them close and insists that they share. Now oxygen has all eight of its electron spots filled. With the majority of the electrons always resting on oxygen’s side of the bonded H20 molecule, water is a polar molecule, and oxygen holds the negative side of the bond, while the hydrogens hold a positive charge. Now, speaking of water molecules…

Hydrophilic

Hydrophilic means “water loving,” and hydrophilic molecules are receptive to water and are likewise in the polar group of molecules. Hydrophilic molecules can bind with water, and thus they make up substances that can dissolve in water. Sugar and salt are examples of hydrophilic substances, but even the Titanic, 2 miles down at the bottom of the ocean, is slowly dissolving in water and corroding away. Water is not easy to resist.

Hydrophobic

Water is not impossible to resist, however: hydrophobic molecules resist water, repel it even, or as the name suggests, they are phobic or “fearful” of water. Examples of hydrophobic molecules are oils, fats, and lipids that will not dissolve in water.

Elementary science: put some colorful oil and water into one clear bottle, shake up it like crazy, and then watch as the oil and water slowly return to their own sides of the bottle. Oil will float to the top, and water will pool on the bottom. As hydrophilic molecules dissolve in water and are polar, hydrophobic ones will only dissolve in oil and are nonpolar.

Amino Acids

Amino acids are the building blocks of protein structures in the body and are each made up of several molecular groups. Each amino acid has a core alpha carbon atom (Cα), and attached to that is a single hydrogen atom, a carboxyl group (-COOH), and an amino group (-NH2).

If you think of an amino acid structure as a four-member band like the Beatles, the alpha carbon is their manager Brian Epstein. The alpha carbon manager then signs on (or rather peptide bonds with) Ringo, Paul, and George in a ring structure around him. Then he signs the most defining member of the band, the R group side chain, or as per our metaphor, John Lennon. The R group you can think of as the Radical group, the one that provides each amino acid with its defining functions.

Of the 20 common amino acids, all are defined by their R group’s chain atoms. The nine hydrophobic amino acids are alanine (Ala), glycine (Gly), valine (Val), leucine (Leu), isoleucine (Ile), phenylalanine (Phe), proline (Pro), methionine (Met), and tryptophan (Trp). The nine hydrophilic amino acids are listed below, with the remaining two amino acids tyrosine (Tyr) and cysteine (Cys) defying categorization at this time.

Hydrophilic Amino Acids

To recap: hydrophilic amino acids are polar amino acids, they seek aqueous solutions, meaning they love water and can’t wait to dive in the pool. Here are their amino acid names, with their uses and functions explained and defined.

Hydrophilic amino acids: what do they do?

Arginine

  • Three-letter code: Arg
  • One-letter code: R

Arginine is a conditionally essential amino acid. Sometimes the body is able to synthesize arginine in-house, and sometimes (in young and premature infants for example, or in extreme cases of trauma like burn victims), the body needs arginine to come from an outside source. Arginine can be found in foods such as chickpeas, nuts, soybeans, seeds, seafood, poultry, beef, and dairy products.

Arginine plays a role in strengthening the body’s immune system, detoxifying the liver, promoting fertility in males, and keeping supple the skin and joints. Arginine is being researched as a treatment for cancer, AIDS, and impotence.

Asparagine

  • Three-letter code: Asn
  • One-letter code: N

Asparagine is a nonessential amino acid, but though we don’t require it in our diet, it can still be found in seafood, eggs, beef, dairy, soy, nuts, legumes, and asparagus where it was first discovered (hence the name). Asparagine has a necessary role to play in protein synthesis and is used for ideal functioning in the human nervous system (it helps us maintain equilibrium).

Aspartate

  • Three-letter code: Asp
  • One-letter code: D

Nonessential, aspartate or aspartic acid is derived within the body from oxaloacetate, ornithine, or citruline. Aspartate is incredibly important in building protein molecules, and specifically vital to several other essential amino acids like threonine, lysine, isoleucine, and methionine. Aspartate is like the office administrative assistant that gets a raise every year, because the whole place would be a mess without its ongoing support.

Glutamine

  • Three-letter code: Gln
  • One-letter code: Q

Glutamine is a nitrogen transporter, a muscle builder, a sanitation worker (removing ammonia from the liver), and a light rail conductor, able to pass through the blood-brain barrier to assist with our central nervous system. Glutamine may have uses in mental health functioning as a treatment for depression, epilepsy, senility, and schizophrenia, as well as potential to benefit those with Crohn’s disease and other intestinal disorders.

Glutamine is popular as a supplement among bodybuilders, and for good reason: up to 60% of muscle tissue in the body is made of glutamine. Because of its ability to build muscle mass, glutamine is also used for those with potentially muscle-wasting medical conditions like cancer and AIDS.

Glutamine can also be gained from many foods, but its sources (leafy green vegetables such as parsley and spinach) should be eaten raw, as cooking them negates the glutamine content.

Glutamate

  • Three-letter code: Glu
  • One-letter code: E

A neurotransmitter, glutamate is the anion of glutamic acid and is a nonessential amino acid. Important in cellular metabolism, glutamate plays a role in memory and learning, and primarily functions and resides in the brain.

Histidine

  • Three-letter code: His
  • One-letter code: H

An essential amino acid, histidine develops the myelin sheaths in the brain, which coat our nerve cells and allow for the transmission of electrical messages. Balance is important when it comes to histidine, as too much of it has been linked to disorders like schizophrenia and anxiety, while too little has been linked with deafness from nerve damage, as well as rheumatoid arthritis.

Histidine is important in sexual health, as it’s responsible for the chemical (histamine) that stimulates sexual arousal. With roles in the immune system and a contributing factor in digestive health, histidine is invaluable. A detoxifier, it can be gained from eating high-protein foods like wheat, rice, rye, dairy products, and meat.

Lysine

  • Three-letter code: Lys
  • One-letter code: K

An essential amino acid, lysine can be obtained from eggs, milk, cheese, potatoes, fish, red meat, soy products, and lima beans. Antiviral, it helps prevent cold sore and herpes outbreaks and is important for bone growth and health. Supplemented for those with shingles or other viral outbreaks, lysine also speeds injury recovery and muscle strength.

Serine

  • Three-letter code: Ser
  • One-letter code: S

Serine (like threonine below) possesses a hydroxyl group in its chemical structure, meaning there’s an extra oxygen atom bonded to a hydrogen atom. Lack of serine may be associated with fibromyalgia, chronic fatigue syndrome, insomnia, depression, and anxiety, and is essential in healthy brain functioning.

A nonessential amino acid, serine is derived from glycine, resides in the myelin sheaths covering our brain’s nerves, and produces the phospholipids that contribute to making every cell in the human body. From the immune system, to the central nervous system, to the muscles of the heart, serine is invaluable.

Threonine

  • Three-letter code: Thr
  • One-letter code: T

Threonine is an essential amino acid that can be obtained from food sources like meat, poultry, fish, sesame seeds, lentils, and cottage cheese. Threonine is needed to make both glycine and thus its derivative, the above serine. It also supports the immune system by aiding the supply of antibodies, is involved with liver function, and contributes to cardiovascular health. Useful for treating ALS (or as it’s commonly known, Lou Gehrig’s disease), threonine may lessen the symptoms of the condition.

Water, Water, Everywhere

Hopefully now you have a solid understanding of the nature and designation of the different amino acids in the hydrophilic category. Go forth with this knowledge, and if you love water too, go swimming the next time you get a chance.

What Are Nonpolar Amino Acids?

What are nonpolar amino acids? This article will help explain how these amino acids are designated and what purpose they serve in the body.

Of the 20 common amino acids in the human body that build protein structures, 9 of them are essential (meaning we must eat or otherwise consume them to get them), and half of them are nonpolar. What are nonpolar amino acids? Which are they, and what does “nonpolar” mean? The review of the topic in this article will help explain.

The Definition of a Nonpolar Molecule

The nonpolar molecules we’ll be talking about are hydrophobic amino acids, meaning “water fearing” because they don’t mix with water molecules. You know how oil and water don’t mix? That’s because oil is hydrophobic.

The opposite of a nonpolar molecule is, as you might guess, polar. Polar molecules are hydrophilic, meaning “water loving.” If you’d like to visualize: polar molecules are like puppy dogs who love water so much that they’ll go barreling straight into muddy or smelly water after a tennis ball, with no hesitation at all. That would make nonpolar molecules like cats, better known for avoiding water, no thank you, and cleaning themselves without it.

Molecules are classified this way based on the charges on the atoms bonded together to form the molecule. If you remember your first taste of high school chemistry, you may remember that atoms have a nucleus of neutral neutrons and positive protons in the middle, and negative electrons swirling all around. Protons have a positive charge that draws electrons to it, like how opposites attract.

When two atoms bond together, they share electrons. Two atoms of the same element have equal positivity, so don’t have the power to steal electrons from the other. These molecules are nonpolar because they have no resulting charge. When atoms of two different elements connect together, invariably one of them will have the higher charge and attract the most electrons to its end of the joint molecule. That means the molecule is polar, or charged, and that charge will then be identified as either a positive or negative charge.

Examples of Nonpolar Molecules

Methane gas is an example of a nonpolar molecule that is created during the breakdown of food and released as a gas (or more colloquially, a fart). Methane is made up of one carbon atom that is bound to four hydrogen atoms: this hydrogen bonding allows the atoms to all share electrons equally, so this smelly molecule has no charge and is nonpolar.

Inside our body, we have both polar and nonpolar molecules, which includes those 20 amino acids mentioned above.

Nonpolar Amino Acids

The chemical properties of amino acids are largely determined by one group of molecules, what’s known as the R group: a side chain that differs on each amino acid. To visualize the amino acid groups, picture a pizza with four toppings, and a little support table in the middle that’s there to keep the cheese from sticking to the lid. That table is the alpha carbon to which all the groups or toppings are attached.

Every amino acid has three groups/toppings in common: the amino group (-NH2), the carboxyl group (COOH), and a hydrogen atom, which in pizza terms would be three standard toppings, say pepperoni, sausage, and cheese (cheese is hydrogen, which is just one atom and not a group of them, and so it gets the plainest topping). That fourth quarter of the pizza? That is the R group, the functional group that identifies and characterizes different amino acids—when you think of the R group, think R for Radical, because that is a completely different and unique topping, and every R group amino acid side chain has a distinct flavor of its own. To get up to 20 it would have to be pineapple, spinach, olives, Canadian bacon, jalapeño, garlic, anchovies, bell pepper, salami, feta cheese, beef, oregano, bacon, barbecue sauce, chicken, pesto, chorizo, broccoli, eggplant, and mushroom. Some are weirder than others.

The nonpolar amino acids have R groups mostly made up of hydrocarbons, though the amino acids methionine and cysteine also each feature a sulphur atom. The nonpolar amino acids are as follows, with more information on each one.

Glycine

  • Three letter code: gly
  • One letter code: G

The body needs glycine to make compounds like as glutathione, creatine, and collagen, which is the most abundant protein in your body. Collagen is a vital part of your muscles, blood, skin, cartilage, ligaments, and bones. Glycine may also protect your liver from alcohol damage, contribute to heart health, and improve your sleep quality. Glycine might also protect those with type 2 diabetes from muscle-wasting. You can gain more glycine by eating certain meat products or by taking a collagen supplement.

Alanine

  • Three letter code: ala
  • One letter code: A

Alanine is an amino acid that helps convert glucose into energy and helps eliminate excess toxins from your liver. Alanine keeps muscle protein from being cannibalized by the body during intense aerobic exercise or activity, and it’s needed to balance nitrogen and glucose levels in the body, which it does via the alanine cycle.

Alanine is a nonessential amino acid, which means that usually your body can make the substance on its own and doesn’t need you to ingest it from outside. However, people with eating disorders, extremely low-protein diets, diabetes, liver disease, or certain genetic conditions that cause UCDs (urea cycle disorders), may need to take a supplement or adjust their diet to gain this amino acid.

Good sources of alanine are meat, fish, poultry, eggs, and dairy products, as well as some protein-rich plant foods, like avocado. There are supplements containing alanine on the market, however, taking any one amino acid alone could upset the balance of nitrogen in the body, putting stress on the liver and kidneys as they try to eliminate waste. It is advisable that those with liver or kidney disease should consult a trusted medical professional before taking any amino acid supplement.

Proline

  • Three letter code: pro
  • One letter code: P

Proline is needed for the manufacture of cartilage and collagen, which helps heal cartilage and cushion our joints and vertebrae. It keeps joints flexible, and skin supple when it is affected by sun damage or signs of normal aging. Proline breaks down proteins for cell creation, and is essential at sites of injury where the tissue must be rebuilt to heal. Proline supplementation is sometimes valuable to people with chronic back pain or osteoarthritis.

Proline is also needed for the maintenance of muscle tissue, and is sometimes found low in long-distance runners and other serious athletes. Proline is usually nonessential, as the body naturally derives proline from its supplies of glutamic acid. However, if necessary, proline can be found in natural sources like dairy, meat, and eggs, or can be gained from amino acid supplementation.

Valine

  • Three letter code: val
  • One letter code: V

Valine is a branched-chain amino acid (BCAA) that works with the other two BCAAs (isoleucine and leucine) to regulate blood sugar, repair tissues, and provide the body with energy. Valine assists in stimulating the central nervous system and is necessary for mental functioning. Valine helps provide muscles with extra glucose energy during intense physical activity, which prevents muscle breakdown, and helps remove toxic excess nitrogen from the liver. Valine may help the liver and gallbladder recover from damage due to alcoholism or drug abuse, as well as help possibly reverse alcohol-related brain damage, or hepatic encephalopathy.

Valine is an essential amino acid, and must be obtained through a diet including meats, mushrooms, dairy products, peanuts, and/or soy protein. Most people have no problem getting enough valine, however maple syrup urine disease or MSUD is caused by an inability to metabolize leucine, isoleucine, and valine. Supplementation is sometimes warranted in those with low-protein diets or who are trying to build muscle mass, but be advised that too much valine intake will make one’s skin feel like it is crawling, and may cause hallucinations. Supplements should always be taken responsibly.

Leucine

  • Three letter code: leu
  • One letter code: L

Leucine helps with blood sugar regulation, muscle repair, and energy production. It also helps burn fat located deep inside the body that is hard to reach through diet and exercise alone.

Leucine is a branched-chain amino acid (BCAA) along with valine and isoleucine, all of which help to promote post-exercise muscle recovery, leucine being particularly effective, as it converts to glucose the fastest of the three. That is also why leucine is closely linked with the regulation of blood sugar, and why a leucine deficiency causes symptoms like hypoglycemia: headaches, fatigue, dizziness, confusion, depression, and irritability.

Leucine promotes the recovery of skin, bones, and muscle tissue after injury or surgery. Natural sources of this essential amino acid are meat, nuts, soy flour, brown rice, beans, and whole wheat.

Isoleucine

  • Three letter code: ile
  • One letter code: I

An isolated form of leucine, isoleucine is prized by bodybuilders for its ability to increase endurance, help repair muscle tissue, and encourage clotting at sites of injury. Isoleucine is broken down for energy inside muscle tissue, and helps stabilize energy levels by aiding in blood sugar regulation. An isoleucine deficiency also produces symptoms that mimic hypoglycemia.

Isoleucine is an essential amino acid, and food sources include high-protein options like nuts, peas, lentils, seeds, meat, eggs, fish, and soy protein.

Methionine

  • Three letter code: met
  • One letter code: M

An essential amino acid that helps the body process and eliminate fat, methionine contains sulfur, a substance required for the production of the body’s natural antioxidant, glutathione. The body also needs methionine to produce two other sulfur-containing amino acids, cysteine and taurine, which help the body eliminate toxins, build tissues, and promote cardiovascular health.

Methionine helps the liver process fats (lipids), preventing accumulation of too much fat in the liver, which is essential for the elimination of toxins to stay functional. Methionine is needed to make creatine, a nutrient found mainly in muscle tissue and often taken as a supplement to boost athletic performance. Methionine is also needed for collagen formation, which is then used to make skin, nails, and connective tissue. One study suggested that taking 6 grams of methionine a day can improve memory recall in AIDS patients who otherwise show a marked methionine deficiency. Methionine may also help treat symptoms of Parkinson’s disease.

Methionine is an essential amino acid, and can be gained from eating garlic, beans, seeds, eggs, fish, lentils (in lower levels), meat, onions, soybeans, and yogurt.

Tryptophan

  • Three letter code: trp
  • One letter code: W

Tryptophan is an essential amino acid that helps balance nitrogen in adults and growth in infants. It also creates niacin, which is needed to create the “happy” neurotransmitter serotonin. In this way, tryptophan helps influence relief from depression and anxiety, managing pain tolerance and increased emotional well-being. Tryptophan is also associated with promoting deeper sleep.

You can get tryptophan through certain foods or a supplement in powder form. Natural food sources include cheese, milk, fish, turkey (famously), chicken, eggs, pumpkin and sesame seeds, chocolate, as well as tofu and soy.

Phenylalanine

  • Three letter code: phe
  • One letter code: F

Phenylalanine is an essential amino acid that is needed for the functioning of the central nervous system. It has been successfully used to help control feelings of depression and chronic pain, and other diseases linked to a malfunctioning central nervous system. Especially effective for treating brain disorders, phenylalanine is able to penetrate the blood-brain barrier, and only chemicals that are able to cross that barrier can directly influence brain function.

Phenylalanine is used to make epinephrine, dopamine, and norepinephrine, neurotransmitters that control how you perceive and interact with the world around you. Phenylalanine supplementation can help you feel happier and more alert, and it also has been used to treat chronic pain and improve cognitive function. An essential amino acid, phenylalanine is normally obtained from high-protein foods like meat, fish, chicken, eggs, milk, dairy products, beans, and nuts.

Cysteine

  • Three letter code: cys
  • One letter code: C

Cysteine is an amino acid containing a sulfur atom, and is used to form healthy bones, skin, hair, and connective tissue. It is also needed to make glutathione, one of the body’s natural antioxidants that fight free-radical damage. Cysteine and glutathione work together to remove toxins from the liver, and cysteine is often used in emergency rooms to treat acetaminophen overdoses before they can cause liver damage. It also protects the brain and liver against toxins from alcohol and cigarettes, and may be useful in preventing hangovers.

Cysteine is a nonessential amino acid, which means the body manufactures it in-house, but foods such as meat, eggs, dairy products, and whole grains are also good sources of cysteine.

Nonpolar Knowledge

There you have the rundown of the amino acid nonpolar side chains, the nonpolar aminos that variously help form protein molecules in our bodies, and do so much to keep us alive and functioning at top form.

Best Amino Acids for the Ketogenic Diet: Which Ketogenic Amino Acids Should You Be Eating?

The value of a ketogenic diet? To burn fat rather than just lose weight on the scale. The core question: in what foods can the six essential ketogenic amino acids be found?

The value of a ketogenic diet? To burn fat rather than just lose weight on the scale. Beginners at dieting often attempt to lose weight with short-term crash diets, which put the body in starvation mode and cause it to stockpile more fat as soon as possible (an evolutionary protection against times of famine). Conversely, the ketogenic diet puts the body into more of a sustainability mode, a stable way to reduce and optimize calorie intake, while focusing on foods that provide the essential amino acids for the ketogenic conversion of fat into energy.

So which ketogenic amino acids should you be eating, and where can you find them?

Amino Acids: the Fat Burning, the Sugar Forming, and the Switch Hitters

The building blocks of protein, amino acids can be categorized as exclusively ketogenic, exclusively glucogenic, or like Dr. Jekyll and Mr. Hyde: radically both. This is based on the end products produced during amino acid metabolism.

Essential amino acids for the ketogenic diet.

As you can see, the predominant category is the glucogenic group, with 13 amino acids. The carbon skeletons that result from the breakdown of glucogenic amino acids can be used via gluconeogenesis to synthesize glucose, simple sugar and an important energy source found in many carbohydrates. These are not the amino acids that will derive energy from your body’s pre-existing fat stores.

The second largest category contains five amino acids, the switch hitters that when catabolized can yield both glucogenic and ketogenic products.

Exclusively ketogenic amino acids are just that: exclusive. Lysine and leucine are the only two amino acids that produce Acetyl CoA or Acetoacetyl CoA without any glucogenic byproducts.

Acetyl CoA (the precursor of ketone bodies) and Acetoacetyl CoA are the first steps of the Krebs Cycle of energy production, which combines glycolysis and pyruvate oxidation with the citric acid cycle (which itself includes α-ketoglutarate, succinyl CoA, fumarate, and oxaloacetate—all byproducts of glucogenic amino acids). To access citrate synthase, the catalyst of this cycle, without glucose or carbohydrates is the value of ketogenic amino acids: it’s like buying the product you need without bringing home any unnecessary or harmful packaging around it.

Acid Eater: the Amino Acids Essential to a Ketogenic Diet

Classes of amino acids can be further categorized as essential vs. nonessential, essential being the ones you must eat to obtain, and nonessential being those that naturally occur in the body, and are not reliant on the food you eat.

Nonessential amino acids:

  • Asparagine
  • Alanine
  • Glutamic acid
  • Aspartic acid

Essential amino acids:

  • Histidine
  • Valine
  • Methionine
  • Isoleucine
  • Phenylalanine
  • Threonine
  • Tryptophan
  • Leucine
  • Lysine

You may have noticed those last two are the exclusively ketogenic amino acids, meaning they only come from sources outside the body. Likewise, four out of five of the switch hitter or versatile amino acids are on this essential list as well, excluding only tyrosine, a conditional essential, as it’s derived from phenylalanine (which is itself essential). Regardless of that particular debate, the core question remains: in what foods can the six essential ketogenic amino acids be found?

The Key Ingredients to Ketogenesis

Intro 101 of the keto diet is to go deeper when dieting, to the cellular level of biological sciences. This is more advanced than the grocery aisle surface choices people often make between low-carb and no-sugar-added options. It’s important to remember that the colorful labeling on the front of food packages can often be subjective. It’s better to know how to read the nutrition label with a keen (keto) eye.

Better yet, know what basic foods have the ketogenic keys to turn fatty acids into ketone bodies. These ketone bodies will then provide energy from your fat stores, without adding carbohydrates, and without impacting insulin or blood sugar levels. Here are where the six essential ketogenic amino acids reside.

1. Isoleucine

Along with leucine and valine (glucogenic), isoleucine is an isomer (isolated form) of leucine that is one of the three branched-chain amino acids (BCAAs), all of which help to promote post-exercise muscle recovery. Involved in hemoglobin production, isoleucine can be found in:

  • Protein sources like meat, fish, and eggs
  • Dairy, particularly cottage cheese
  • Seeds, grains, nuts, and beans including almonds, brown rice, cashews, lentils, and chia seeds

2. Phenylalanine

The source of tyrosine and one of the aromatic amino acids, phenylalanine is used in the biosynthesis of norepinephrine, dopamine, and thyroid hormones (huge players when it comes to mental health). Possibly effective in treating mood disorders, phenylalanine is contained in:

  • Olives, figs, raisins, avocados, pumpkins, and most berries
  • Meat, chicken, fish, and eggs
  • Rice, beans, quinoa, and seeds
  • Spirulina, seaweed, and leafy greens

3. Threonine

An essential nutrient in the diet of vertebrates, threonine supports the central nervous system, along with the heart, liver, and immune system. A key component in the production of collagen, elastin, and muscle tissue, threonine can be gained from:

  • Beans, nuts, lentils, and quinoa
  • Lean beef, lamb, pork, and chicken/turkey
  • Seafood including shellfish, particularly salmon, whelks, cuttlefish, octopus
  • Seeds, including chia and hemp seeds
  • Raisins, figs, avocados, and pumpkin
  • Spirulina, watercress

4. Tryptophan

Needed for nitrogen balance, tryptophan is also used to produce melatonin (for regulating sleep and wakefulness), niacin, and serotonin, the neurotransmitter known as the “happy” chemical. Tryptophan can be found in:

  • Turkey (rather famously), as well as red meat, rabbit and goat meat, eggs, and fish
  • Milk and cheese, particularly reduced fat mozzarella
  • Pumpkin and squash seeds, along with chia, sesame, and sunflower seeds
  • Almonds, peanuts, bananas, and chocolate (ideal ingredients for a sundae)
  • Spirulina

5. Leucine

Another of the BCAAs, and one of the two exclusively ketogenic amino acids, leucine builds muscle by stimulating protein synthesis. It can be sourced from:

  • Nuts, peas, beans, seeds, and pumpkins
  • Chicken, beef, and pork
  • Seafood including tuna
  • Soybeans, whey protein, and plant proteins
  • Cheese, particularly Parmesan

6. Lysine

Necessary in the formation of collagen, connective tissue, and muscle growth and repair in the body, lysine can be found in:

  • Protein sources like meat, poultry, seafood, and eggs
  • Beans, peas, almonds, cashews, and chia seeds
  • Spirulina, parsley
  • Cheese and yogurt
  • Whey protein

The Ketogenic Conclusion

You may have noticed some foods dominating the field; when it comes to essential amino acids for a ketogenic diet, where you find a good source of protein, you often find the ketogenic advantage. Donald K. Layman, Ph.D. along with Nancy R. Rodriguez, Ph.D. penned a paper for Nutrition Today titled “Egg Protein as a Source of Power, Strength, and Energy,” but in it pointed out that egg is not the only food that packs that much value. With so many high-yield proteins, any dietary practice—be it vegetarian, vegan, kosher, or allergy-restrictive—can still gain you the essential amino acids for perfecting your ketogenic journey if you’re diligent about ensuring your protein macros.

Your body is not so much a temple as a laboratory, a series of chemical reactions. Providing your body with the right ketogenic amino acids (instead of an overabundance of glucose precursors) sets you up for the ideal fat-burning catabolic pathways. This leads to healthy protein turnover for muscle growth, weight loss, and the energy to propel you forward.

Taking an essential amino acid supplement (which includes the ketogenic amino acids lysine and leucine) can help protect against any protein insufficiencies you may encounter while following dietary restrictions, such as the high-fat, moderate-protein requirements of the keto diet.

Foods That Are Rich in Sulfur and Why You Should Be Eating More of Them

A diet that contains sulfur-rich food is necessary for keeping connective tissue flexible and helping the body detox and metabolize food. Get enough sulfur by eating a protein-rich diet that includes Brussels sprouts, kale, meat, and eggs.  

As an essential mineral found in proteins and the amino acids cysteine and methionine, sulfur is a critical nutrient for the human body. Sulfur is most likely known best for its sulfur compounds, which give garlic its distinctive aroma, cause tears when chopping onions, and lend a funky smell to urine, but sulfur does so much more. The mineral stabilizes and shapes some protein structures, aids in metabolism and detoxification, and keeps connective tissue and cartilage supple, making it essential that our diets contain sulfur-rich foods.

Good Sources of Sulfur-Rich Foods

Sulfur doesn’t discriminate by diet. Whether you’re a meat lover or a plant-based eater, there’s a wealth of sulfur-rich foods to choose from.

Meat, Fish, Poultry, and Other Proteins

Building and maintaining healthy skin, nails, and hair depend on protein-rich foods, such as fish, poultry, meats, nuts, and legumes. Packed with protein, eggs are also an optimal source of sulfur, which is found in both the egg yolk and the white, although sulfate content is higher in egg whites.

Protein-rich foods contain sulfur in the form of the amino acids cysteine and methionine. These amino acids provide the amounts of sulfur our cells need to function properly. In addition to helping make protein, sulfur serves as a cofactor for enzymes that result in chemical reactions.

Cruciferous Vegetables

Many fibrous, often green and non-leafy vegetables fall into the category of sulfur-rich vegetables. Cruciferous vegetables, such as wasabi, horseradish, cabbage, kale, bok choy, Brussels sprouts, and cauliflower, pack a punch when it comes to nutrients.

Brussels sprouts, asparagus, and legumes also are very high in methylsulfonylmethane (MSM), which provides a major source of sulfur. Additionally, these cruciferous veggies provide healthy doses of fiber, vitamins C, E, and K, folate, and carotenoids, as well as the sulfur-containing chemicals known as glucosinolates. Thank these chemicals for the bitter flavor and distinctive, pungent aroma that set cruciferous vegetables apart from so many others. When glucosinolates break down, for example during digestion, they form compounds, including indoles and isothiocyanates. Researchers have studied these specific compounds most often for their anti-cancer effects. Studies have shown that the compounds, indoles, and isothiocyanates can have antiviral and antibacterial effects, as well as anti-inflammatory properties.

Alliums

Other foods high in sulfur include allium vegetables, like leeks, garlic, chives, and onions. They contain organic compounds that contain sulfur, and studies in animals have shown that these vegetables may help prevent esophagus and colon cancers. Though more clinical trials need to be performed to determine their efficacy in humans, this research shows that the cancer-fighting potential of alliums warrants further exploration.

Stay healthy with a sulfur-rich diet.

Understanding Amino Acids

Most commonly referred to as the building blocks of protein, amino acids assist in many biological functions. There are 20 amino acids in protein. Nine of them are essential, which means we must get them through nutrition because our bodies don’t produce them on their own. Since our bodies do not store them, adults need to eat healthy diets to get these nine essential amino acids: valine, leucine, lysine, isoleucine, methionine, phenylalanine, tryptophan, threonine, and histidine.

The other remaining amino acids fall into the categories of nonessential and conditionally essential. Nonessential amino acids are naturally occurring in our bodies, and we can also get them from the foods we eat. Alanine, asparagine, and aspartate are examples of nonessential amino acids.

Arginine, glutamine, tyrosine, cysteine, glycine, proline, serine, and ornithine are both nonessential and conditionally essential. This means our bodies synthesize them, but during times of sickness or stress, we may not be able to produce the amount we need. In those instances, we must ensure our amino acid needs are met through our diets or with supplementation.

Only two amino acids, methionine and cysteine, contain sulfur. Methionine is critical for good health because it is required to build proteins and produce many molecules in the body, including SAM, which is used to modify DNA. Methionine also plays a critical role in many cell functions and helps prevent liver damage in acetaminophen poisoning.

Why the Consumption of Sulfur Foods Matter

In addition to providing strength and resiliency to hair, sulfur assists in many other biological processes.

Sulfur is needed to synthesize the tripeptide glutathione, which is a chain of three amino acids that is joined by two peptide bonds. Not only is glutathione a key antioxidant, but it also regulates a number of cellular processes. It helps to control the rapid production of cells, aids in the detoxification of foreign organisms and free radicals, and influences immune function.

Sulfur is integral in binding together the two chains of amino acids that form the hormone insulin, which regulates our bodies’ sugar use. Taurine synthesis also depends on sulfur. Taurine is an organic compound that contains sulfur and plays an important role in metabolizing fats, restoring insulin sensitivity, and supporting the general functions of muscles and the central nervous system.

How Much Sulfur Do We Need?

The recommended dietary allowance set forth by the Food and Nutrition Board of the National Research Council/National Academy of Sciences for methionine plus cysteine is 14 mg/kg of body weight per day. Regardless of age or sex, a person weighing 70 kilograms would need to consume about 1.1 grams per day.

Who Suffers from Low Sulfur Levels

Though sulfur is one of the most abundant minerals in our bodies and many foods contain the mineral, we can suffer from low sulfur levels. First, the American diet often includes many processed foods and carbohydrates, and not many high-protein foods. A low-protein diet can result in low sulfur levels. Sometimes, those who eat little or no protein from animals, such as vegetarians and vegans, also may have lower amounts of sulfur in their systems.

Even when we eat balanced diets, we may not have the sulfur content levels we expect. Overcooking sulfur-rich foods can compromise their nutrition, negatively impacting the amount of the mineral our bodies get. Also, industrialized farming practices impact the levels of sulfur in the soil where crops grow. The bottom line is that if we are not buying and consuming local, organic produce or acquiring our meat and produce from grass-fed animals, there’s a very great chance we are not getting the essential vitamins and minerals our bodies need.

What Are Polar Amino Acids?

There’s more to amino acids than first meets the eye. There are actually two types: polar and non-polar. Here we uncover the polar amino acids and what they mean for you and your health.

When most people think of amino acids, they probably have a vague memory of their high school science teacher discussing the building blocks of protein. But did you know there are actually two types? Known as non-polar and polar amino acids, each group is classified according to its side chains—the shorter chains of atoms attached to the main chain, or backbone, of a molecule.

When amino acids join together to form proteins, only their side chain groups are exposed and able to interact with each other and their surroundings. And the shape of the protein—yes, proteins really do have shape—is determined mainly by the sequence of amino acids in that chain.

The non-polar groups are hydrophobic amino acids, which means they have side chains that are repelled by water. These amino acids are thus located in the protein core, safely tucked away from any contact with water.

In contrast, polar amino acids have hydrophilic side chains, which means they’re actually attracted to water and participate in hydrogen bonding with the highly polar water molecules. Because of this water-loving characteristic, these amino acids are generally located on the surface of proteins, in contact with the aqueous cell environment.

Interestingly, although the hydrophilic nature of polar amino acids means that they readily dissolve in water, they actually have the opposite reaction when placed in oil. In this case, instead of dissolving, the presence of the oil results in the amino acids being attracted to each other.

Which Amino Acids Are Polar?

There are many different amino acids, with over 300 known forms listed in the Practical Handbook of Biochemistry and Molecular Biology. However, only 20 are used to synthesize proteins.

These 20 amino acids are known as the common amino acids. Of these, 10 are considered polar. Including their three-letter codes, these amino acids are:

Arginine (Arg)
Histidine (His)
Asparagine (Asn) Lysine (Lys)
Aspartate (Asp) Serine (Ser)
Glutamine (Gln)
Threonine (Thr)
Glutamate (Glu)
Tyrosine (Tyr)

Contrast these with the non-polar amino acids, which are:

Alanine (Ala)
Phenylalanine (Phe)
Glycine (Gly) Proline (Pro)
Isoleucine (Ile) Tryptophan (Trp)
Leucine (Leu) Valine (Val)
Methionine (Met)

What Are the Properties of Polar Amino Acids?

The polar amino acids can be further broken down into neutral, basic, and acidic groups. And each of these categories functions in a different way.

1. Neutral Polar Groups

As the name suggests, neutral polar amino acids are neither basic nor acidic. This means that their side chains contain exactly one amino group and one carboxyl group (hence the name “amino acid”). The majority of amino acids, both polar and non-polar, are in fact neutral. Of the polar amino acids, asparagine, glutamine, serine, threonine, and tyrosine are neutral.

2. Acidic Polar Groups

If the side chain contains an extra element of carbolic acid, the amino acid becomes acidic. Aspartate and glutamate are acidic amino acids. These forms are also known as aspartic acid and glutamic acid, respectively. The aspartate and glutamate types are the anions, or negatively charged ions, of these substances.

3. Basic Polar Groups

If the side chain contains an extra nitrogen group, the amino acid becomes basic. Arginine, histidine, and lysine are basic amino acids and have a positive charge.

Group Polarity

The degree of polarity is also determined by the functional groups—the groups of atoms that dictate the chemical behavior of a compound—contained in the side chains. In the case of polar amino acids, this refers to the various combinations of amide and carboxylic acid groups that interact to create the neutral, acidic, and basic forms.

What Role Do Polar Amino Acids Play?

Like the rest of the common amino acids, the neutral, acidic, and basic polar groups all perform important functions in the body. Some of these include:

Polar amino acids for optimal health.

More to Learn

You may have noticed that we mentioned 20 common amino acids earlier but listed only 19. While it may have looked like we were bad at math, we promise we really knew what we were doing when we left cysteine (Cys) out of our lists.

You see, cysteine is classified as only slightly polar and thus doesn’t fit well into either the polar or non-polar category.

In fact, where amino acids are concerned, researchers continue to disagree on several points, including whether certain forms should be considered polar or hydrophilic.

So, as you can see, even though we’ve come a long way in our understanding of amino acids and the important roles they play in the human body, we still have more to learn before we can say we’ve truly mastered all the intricacies of these essential building blocks of life.