We all know the importance of diet and exercise for weight loss—along with a sustained commitment to losing weight and keeping it off. And there is, unfortunately, no magic weight-loss pill that can help us shed the pounds and keep them off for good. But there are some pretty miraculous organic compounds that not only prime your body for weight loss but also help boost your metabolism. And these little building blocks of protein are completely safe and natural too. So come with us as we explore amino acids for weight loss and discover the many ways they can support your body’s metabolism and help you reach your weight management goals.
Amino Acids and Metabolism
Our bodies are constantly burning carbohydrates, fats, and proteins to provide the energy our cells need to perform the thousands of biochemical reactions that are continuously taking place throughout the day.
The sum total of the energy utilized by all these reactions is called the basal metabolic rate—the body’s rate of energy production when it’s at rest and not actively digesting food.
Because the basal metabolic rate is determined when the body’s at rest, the best time to measure the rate is when you’re sleeping (but since that’s not really practical for most of us, there are a number of online calculators available that can help you estimate your personal basal metabolic rate).
What’s more, the same basic metabolic functions that determine the basal rate of energy expenditure are also going on when the body’s active.
So, by adding the basal rate—which occurs continuously—to the amount of energy expended during daily activities, it’s possible to determine the body’s total metabolic expenditure (thankfully, there are online calculators that can help you measure this too).
Granted, this is all rather technical, but it helps us illustrate the fact that weight-loss promotions and articles that feature the appealing words “boost your metabolism” are really just saying, “Increase your basal metabolic rate.”
Here’s how it works: if your basal metabolic rate is greater than the number of calories you consume in a day, you’ll lose weight.
To express this in a slightly different way, if you can rev up your basal metabolic rate (i.e., boost your metabolism), you’ll lose body weight even if you maintain the same caloric intake—which is great news for those of us who don’t fancy eating a lower calorie diet.
There are two major contributors to the body’s basal metabolic rate:
- Reactions involved in maintaining a proper balance between sodium and potassium levels in the blood and inside the cells and reactions that use energy, such as those that make glucose
- The energy cost of protein turnover
Although it’s difficult to do much about the first, you can definitely increase the rate of protein turnover and thus boost your metabolism.
What Is Protein Turnover?
Protein turnover refers to the process by which the thousands of proteins in the human body are continuously created and broken down.
Energy, in the form of adenosine triphosphate, or ATP, fuels protein turnover—both the process of tearing protein down and the process of building it back up. Anywhere from one third to one half of our basal energy production is used to fuel protein turnover.
But the exact amount of energy used for protein turnover depends on how much muscle you have (the amount of protein in the rest of the body is pretty constant between individuals) and how fast muscle protein is turning over.
So the most effective way to boost your metabolism—and therefore your fat-burning capability—is to increase your muscle mass.
A 10-kilogram difference in muscle mass, with all else staying constant, equates to about a 35,000-kilocalorie difference in energy expenditure over a year.
And since about 3,500 kilocalories is stored in 1 pound of body fat, a 35,000-kilocalorie difference in energy expenditure translates to a gain or loss of 10 pounds of body fat over the course of a year.
What’s the Best Way to Build Muscle Fast and Increase Muscle Protein Turnover?
If you want to increase muscle protein turnover and build lean muscle fast, then incorporating exercise and protein/essential amino acids (EAAs) into your routine is absolutely essential.
Exercise increases muscle protein turnover for many hours after a workout and can, over a period of time, help contribute to both muscle growth and muscle mass. However, don’t expect major changes in muscle mass from exercise alone because you must increase the amount of protein and EAAs you consume to significantly affect mass.
So increasing dietary protein/EAA intake—whether through food sources, protein supplements like whey protein, or supplemental amino acids—is the key to boosting basal metabolic rate. Doing so will stimulate muscle protein turnover and increase muscle mass over the long term.
Dietary protein—and EAAs in particular—stimulates muscle protein turnover in two respects.
First, amino acid supplements have been shown to increase the basal rate of muscle protein turnover—which means that more energy is used to fuel the increase in protein turnover, thereby giving a persistent “boost” to your metabolism.
And this can have a positive impact on both weight loss and body composition. Check out the results in the figure below.
Second, increased dietary protein and EAA intake helps boost metabolism and promote fat loss by influencing what’s known as diet-induced thermogenesis.
The body’s metabolic rate goes up about 10% for a couple of hours after eating a meal that contains dietary protein or consuming an EAA supplement. The exact amount of the increase depends on how much protein you eat with the meal or how many grams of EAAs you take. This response has been studied for many years and is called diet-induced thermogenesis.
Diet-induced thermogenesis refers to energy lost as heat after you eat protein. This process is only activated by dietary protein or EAAs, as neither dietary carbohydrates nor fats have much effect on metabolic rate.
However, when you consume dietary protein or an EAA supplement, your metabolic rate increases because energy is used to digest the protein and absorb the amino acids.
Therefore, eating a meal that contains dietary protein or taking an EAA supplement increases the metabolic rate by stimulating the rate of protein synthesis in the body, particularly in muscle, since the process of protein synthesis requires energy.
In addition, diet-induced thermogenesis of dietary protein actually lessens the caloric impact of protein.
Calories are classically determined by combusting a food source in a device that measures the amount of energy released. In the case of protein, 4 kilocalories per gram is normally released by combustion, so the caloric equivalency of protein is traditionally considered 4 kilocalories per gram.
This means that you can calculate how many protein calories are in a meal by multiplying the number of grams of protein by 4 kilocalories per gram.
However, since the digestion of protein increases the body’s metabolic rate by approximately 10%, the net caloric intake from the protein component of the meal is actually 10% less—or 3.6 kilocalories per gram—than the value you’d get by following the traditional approach.
So why not just stimulate diet-induced thermogenesis with dietary protein?
Because consuming EAAs increases protein turnover more than any dietary protein can, so EAAs therefore have a greater impact on diet-induced thermogenesis. Take a look at the following figure.
It requires less work for EAAs to be absorbed by the intestines, so on a gram-per-gram basis, it may take less energy for the body to digest them than it does intact protein.
Even so, the consumption of EAAs actually stimulates protein synthesis about three times more than the consumption of intact protein does—thus leading to a greater increase in diet-induced thermogenesis.
Branched-Chain Amino Acids and Weight Loss
The branched-chain amino acids (BCAAs) leucine, isoleucine, and valine are a special group of EAAs that are known to have a direct impact on metabolic health.
Interestingly, although science has known for decades that blood concentrations of BCAAs are elevated in individuals with type 2 diabetes, the link between levels of BCAAs and the development of insulin resistance is not what it may initially seem.
In fact, the theory that dietary BCAAs are somehow to blame for the impaired glucose metabolism that leads to diabetes is contradicted by numerous studies over the past 20 years that have shown that supplementing with BCAAs can improve insulin sensitivity, and that increased concentrations of leucine, in particular, may actually improve blood sugar control.
Because people with insulin resistance and metabolic syndrome—a related group of conditions that includes obesity, insulin resistance, and high blood pressure and cholesterol levels—have greater difficulty losing weight, you might then assume that increased consumption of supplemental BCAAs could be helpful with weight loss.
And while the connection between BCAAs and weight loss has not been studied as thoroughly as the connection between BCAAs and insulin resistance, the research that has been performed on humans would indicate that your assumption is indeed correct.
For example, no human studies have thus far demonstrated any gains in body fat with consumption of BCAAs. In fact, just the opposite has been shown, with current research indicating that a calorie-restricted diet that’s high in BCAAs may actually lead to both greater fat loss and improved muscle retention.
Why Use Amino Acids for Weight Loss Instead of Drugs?
Although a number of both over-the-counter and prescription-based medications are currently being marketed as weight-loss aids, these types of drug-based approaches come with potential negative side effects, some of which may be severe.
By contrast, the stimulation of protein synthesis that occurs after ingesting EAAs is an entirely natural biological process without any known adverse effects. Moreover, long-term consumption of EAAs has been proven to result in a number of health benefits—advantages that aren’t seen with drug therapy.
Yet it’s important to keep in mind that protein synthesis can’t occur unless all EAAs are present in their optimal amounts. So to ensure you’re getting the most out of amino acids for weight loss, always look for a formula that includes a balanced supply of all nine EAAs.