When you evaluate your diet, chances are you consider the ways it will affect your body. If we're being honest, many of us are focused primarily on how the foods we eat impact our physical appearance. However, food not only affects your appearance, but also directly shapes the way you think, feel, and age. By choosing the best food for brain health, you can both protect and enhance your mental capacity. Researchers, including Lisa Mosconi, neuroscientist and author of Brain Food: The Surprising Science of Eating for Cognitive Power, have proven that well-fed brains show increased abilities to process information, recall memories, learn new things, focus on complex tasks, and more. Read on to learn more about optimal eating for brain health and the particular importance of a balanced supply of amino acids.
Understanding the Brain's Unique Nutritional Needs
"What the brain needs to eat differs from what the rest of the body needs to eat," explained Mosconi, who also serves as associate director of the Alzheimer's Prevention Clinic at Weill Cornell Medical College, in an interview. The foods we eat, in combination with our lifestyles as a whole, have a profound impact on our brains, making it crucial to cultivate healthy habits.
Though the brain is one of the most studied parts of the body, it remains one of the most mysterious. The brain, which serves as the coordinating center of sensations as well as intellectual and nervous activity, performs countless functions that are essential to our survival.
To coordinate these essential functions, the brain must rely on a constant stream of signals. These take the form of tiny electrochemical currents, and the brain uses a variety of substances called neurotransmitters to convey them from one region to another.
Three of the most important neurotransmitters—dopamine, serotonin, and norepinephrine—belong to a class of chemicals called monoamines, which regulate our mood states and experiences of fear and pleasure. They also play key roles in many cognitive functions.
To generate neurotransmitters and carry out the rest of its duties, the brain commandeers approximately 20% of the calories you eat in a day. Without a consistent supply of calories, your brain power drops.
Where the calories come from matters too, if you're invested in having a healthy brain. For instance, salmon contains omega-3 fatty acids, necessary ingredients for the creation and maintenance of brain cells. And one of the many benefits of increasing your intake of anti-inflammatory, antioxidant-rich foods is a reduction in cellular stress, which a wealth of research has shown contributes to cognitive decline and neurodegenerative conditions like Alzheimer's disease.
The Basics of Eating for Brain Health
Mosconi and other scientists have used cutting-edge medical imaging and genomic-sequencing studies to further their comprehension of how diet influences brain health. "Nutrition plays a vital role in brain function and aging," said Mosconi.
Some foods have neuroprotective qualities, meaning they help protect brain health and prevent cognitive impairment. Others, however, can actually cause harm to the brain and even raise a person's risk of dementia. A poor diet has a more damaging effect on the brain than any other organ in the body, according to Mosconi.
How the Blood-Brain Barrier Works
Once our digestive system has broken down the food we eat into its constituent nutrient parts, those nutrients can enter the bloodstream and travel through it to reach the brain. Because of the brain's vulnerability, it's protected by a specialized defense system known as the blood-brain barrier. This barrier controls which nutrients can access the brain and which cannot.
"There are also gates in the brain that open and close depending on whether the brain is “hungry.” No other organs in the body have the same strict rules," Mosconi said.
Which Foods Are Best for Brain Health?
Many of the nutrients the brain requires—Mosconi puts the total number of nutrients needed for optimal function at 45—it makes itself. However, there are some indispensable nutrients that must be provided from your diet. Furthermore, during times of illness or stress, it can be quite helpful to bolster the brain's stores of self-produced nutrients.
Here are 10 of the best foods for brain health, all with impressive, research-validated benefits.
Though it does not often appear on lists of superfoods, caviar may just be the most brain-healthy food in existence. The term caviar traditionally refers only to roe (eggs) from wild sturgeon caught in the Caspian Sea and Black Sea, but in some places today, you may see it applied to roe of other species of sturgeon or other fish altogether such as salmon, steelhead, trout, lumpfish, whitefish, or carp.
Though traditional caviar (Beluga, Ossetra, and Sevruga) remains the most sought-after, and the most expensive, other varieties contain the same special mix of nutrients: omega-3s, several B vitamins (choline as well as B6 and B12), magnesium, iron, vitamin A, vitamin C, selenium, and plenty of amino acids.
2. ColdWater Fatty Fish
Given that caviar's price-point exceeds many households' budgets—even relatively affordable picks like wild salmon roe clock in at $19.99 for 3.5 ounces—it's fortunate coldwater fatty fish offer many of the same valuable nutrients at a significantly lower cost.
Fish like Alaskan salmon, mackerel, bluefish, tuna, herring, sardines, and anchovies all contain high quantities of brain health-boosting omega-3s.
According to a 2017 study, individuals with high levels of omega-3s showed correspondingly higher cerebral perfusion (blood flow in the brain). High cerebral blood flow is associated with a decreased risk of cognitive decline and dementia. Per the study cited above, it appears that there may also be a connection between omega-3 levels and improved cognition.
3. Nuts and Seeds
If you're a vegetarian or vegan, you can still find a plethora of food sources for the omega-3 fatty acids your brain craves.
Chia seeds are a fantastic source of plant-based omega-3s that also provides tons of fiber and protein in each serving. A single ounce of chia seeds not only meets, but exceeds, your daily recommended intake for omega-3s, netting you 4,915 milligrams.
Hemp seeds, flaxseeds, and walnuts are also loaded with omega-3s and other healthy fats.
Many nuts and seeds contain troves of vitamin E, a powerful antioxidant that can help keep cells safe from the ravages of free radical-induced oxidative stress. The effects of this form of oxidative stress can become even more pernicious as we age, leading researchers to hypothesize that vitamin E-rich foods may offer protection against Alzheimer's and other forms of dementia.
According to a 2014 review published in Nutrients, research consistently shows a clear association between higher blood levels of vitamin E and improved cognitive function.
Sunflower seeds, almonds, and hazelnuts have some of the highest concentrations of vitamin E.
As discussed above, foods replete with antioxidants can ward off signs of cognitive decline such as memory loss. Many types of berries contain an array of valuable flavonoid antioxidants.
By reducing oxidative stress and inflammation, the antioxidants found in berries produce a range of benefits, including a lower risk of Alzheimer's disease. A review published in Neural Regeneration Research stated that new research shows that antioxidant compounds found in berries, including anthocyanin, caffeic acid, catechin, and quercetin, "can prevent age-related neurodegenerative diseases and improve motor and cognitive functions."
Some of the brain-health benefits noted in the review are:
- Enhanced communication between brain cells
- Lower inflammation levels throughout the body
- Increased plasticity, which encourages the formation of new connections between brain cells, thereby improving learning and memory
- Decreased risk or delayed onset of dementia and cognitive decline
Berries known for their impressive antioxidant content include blackberries, blueberries, strawberries, raspberries, mulberries, blackcurrants, and goji berries.
5. Dark, Leafy Greens
These well-known power players of the health food world have highly desirable benefits for the health of your brain, thanks to the wealth of vitamins, minerals, and antioxidants they contain.
Here, as in other realms, kale takes a place of pride in the superfoods royal court. Kale (and other cruciferous vegetables) provide your body with compounds called glucosinolates, which your body then breaks down into isothiocyanates.
Research indicates that isothiocyanates show formidable neuroprotective effects. According to a 2015 study, isothiocyanates "could be regarded as a promising source of alternative medicine for the prevention and/or treatment of neurodegenerative diseases."
6. High-Glucose, Fiber-Rich Foods
Your brain requires a vast supply of energy (20% of the body's total burn, remember?), and its preferred form of energy is a simple sugar called glucose. It loves glucose so much that the blood-brain barrier allows it to pass directly through to your brain cells.
The downside of our brain's reliance on glucose is that when our blood sugar levels dip too low, that can have a rapid and adverse impact on brain function. Think brain fog, headaches, and other unpleasant and inconvenient symptoms. High blood sugar can also interfere with brain function.
Your brain works best when blood sugar levels remain stable. While simple carbohydrates provide quick energy, using these for brain food leaves you vulnerable to dips and spikes. Complex carbohydrates, however, serve as a more stable energy source.
Foods that pair a high-glucose content with a high-fiber content are ideal for brain health, as they have a more moderate effect on blood sugar levels while still offering your brain the glucose it needs.
Some wonderful options for high-glucose, fiber-rich foods include sweet potatoes, whole grains, beets, and kiwis.
Not only are eggs a great source of amino-acid laden protein, but they also provide plenty of B vitamins, specifically, vitamins B6, B12, and folic acid.
Those three B vitamins can lower blood levels of homocysteine, a biological compound scientists have identified as a risk factor for brain atrophy, cognitive impairment, and dementia.
According to a randomized, controlled trial published in PLOS One, a preeminent peer-reviewed scientific journal, supplementing with vitamin B6, B12, and folic acid can slow the rate of brain atrophy for individuals with mild cognitive impairment.
Soybeans, as well as foods made from soy beans like tofu, provide tons of polyphenols,—specifically, isoflavones like daidzein and genistein—antioxidants linked to a decreased risk of dementia and increased cognitive abilities across age groups.
Soy also contains tyrosine. Though tyrosine is a nonessential amino acid (the body can synthesize it from phenylalanine), research, including this article published by a Belgian scientist, indicates that when you increase your dietary intake of tyrosine, you also increase the ratio of tyrosine to other amino acids like leucine, isoleucine, valine, and tryptophan.
As the article cited above notes, animal studies reveal that a supplemental intake of tyrosine can offset the negative impact of acute stress on cognitive performance, while human studies show it can counterbalance the ill effects of sleep deprivation and chronic stress on cognitive function.
We'll talk more about tyrosine in the section below.
9. Extra-Virgin Olive Oil
When it comes to healthy fats, extra-virgin olive oil ranks unquestionably high on the list.
Extra-virgin olive oil is loaded with beneficial monounsaturated fat as well as potent nutrients proven to keep your brain healthy as you age, like omega-3s and vitamin E. It's also a cornerstone of the Mediterranean diet, an eating approach associated with numerous health benefits, including a lowered risk of dementia.
A research team from the Lewis Katz School of Medicine at Temple University found that extra-virgin olive oil safeguards memory and learning ability while reducing the formation of amyloid-beta plaques and neurofibrillary tangles, two abnormal developments in the brain that signal the onset of Alzheimer's disease.
10. Dark Chocolate
The higher the cocoa, or cacao, content of a particular chocolate bar, the better it is for you. Cacao is a rich source of flavonoids—and the flavonoids found in cacao seem to be especially beneficial for the brain.
Findings published in the British Journal of Clinical Pharmacology indicate that the flavonoids found in cacao, most abundantly, epicatechin, induce widespread stimulation of cerebral blood flow, as well as "angiogenesis, neurogenesis and changes in neuron morphology, mainly in regions involved in learning and memory." The flavonoids in chocolate can lower your risk of Alzheimer's disease as well as your risk of stroke.
As many of us know from lived experience, chocolate can also have a positive effect on mood.
The results of a 2018 study with human participants indicates that dark chocolate with cacao concentrations of 70% and up generate changes in brain activity that correlate to "enhancement of neuroplasticity, neural synchrony, cognitive processing, learning, memory, recall, and mindfulness meditation."
Why Amino Acids Are Particularly Important for Brain Function
Amino acids are the precursors of neurotransmitters, a technical way of saying that amino acids make the neurotransmitters our brains depend on for balance and function. Changes in the production of neurotransmitters can occur when we fail to provide our brain with an adequate supply of amino acids from protein-dense foods. Alterations in the production of these transmitters can, in turn, directly influence the brain’s health.
Three amino acids—tryptophan, tyrosine, and phenylalanine—function as precursors to the production of three key neurotransmitters: serotonin, dopamine, and norepinephrine. Other amino acids also make significant contributions to brain health, like acetyl l-carnitine (a form of the amino acid carnitine), l-glutamine (a form of the amino acid glutamine), and the branched-chain amino acids.
Tryptophan is the rarest of the essential amino acids found in food and is the precursor of serotonin, one of the body’s natural antidepressants. Tryptophan can enhance positive mood and lower obsessive thinking, which is often related to eating disorders, anxiety, and depression.
However, a careful balance is needed, because serotonin is an inhibitory neurotransmitter and an increase can induce a sensation of fatigue and ultimately hasten sleep. The long-standing tradition of dozing off after a big turkey dinner can be attributed (at least in part!) to the relatively high abundance of tryptophan in turkey.
Tyrosine is the precursor of three neurotransmitters: norepinephrine, dopamine, and epinephrine. Tyrosine is not typically considered an essential amino acid because it can be synthesized by humans from phenylalanine; however, studies have shown that in certain instances the brain may not be able to synthesize sufficient tyrosine from phenylalanine to meet its needs. For example, delirium is associated with a low conversion rate of phenylalanine to tyrosine.
As touched on above, while tryptophan and tyrosine are the two primary amino acids connected to brain health, they're not the only amino acids that play a role in brain function.
Carnitine converts fats in the body into fuel that can be used by the brain. This amino acid also removes toxins that interfere with brain activities.
Glutamine improves the uptake of serotonin and dopamine, and stimulates the production of neurotransmitters that assist with brain function and focus. Glutamine can also be converted to the amino acid glutamate, another neurotransmitter.
The branched-chain amino acids (BCAAs)—leucine, valine and isoleucine—make indirect contributions to the production of natural neurotransmitters. The BCAAs, along with phenylalanine, tyrosine, and serotonin, are all transported into the brain by the same transport system. An increase in BCAAs can inhibit the uptake of tryptophan, phenylalanine, and tyrosine by occupying the transporters.
Key Sources of Tryptophan, Tyrosine, and Other Amino Acids
As we've seen, amino acids can be found in protein-dense foods. Some foods contain more of specific amino acids than others, however. Animal protein is the most efficient means of meeting your body's amino acid needs. It is possible to get all the essential amino acids exclusively from plants, but it will require more intentionality. We've included options for vegans and vegetarians on each of the lists below.
6 of the Best Sources of Tryptophan
While poultry and fish provide the most tryptophan per ounce, there are good options for vegetarians and vegans too. Red meats also contain this amino acid, but they should be eaten in moderation because they have more saturated fat.
1. Turkey and Chicken
The best dietary sources of tryptophan are turkey and chicken. A 4-ounce portion of turkey or chicken breast provides 350 to 390 milligrams of tryptophan.
Shrimp is also a good source of tryptophan. A 4-ounce serving contains 330 milligrams.
3. Other Types of Seafood
Fish, such as tuna, halibut, salmon, sardines, cod, and scallops, contains between 250 and 400 milligrams of tryptophan per serving.
4. Pumpkin Seeds
Among nuts, pumpkin seeds are the best sources because they provide 110 milligrams of tryptophan per one-fourth cup.
Legumes, such as kidney beans and black beans, contain 180 milligrams of tryptophan per cup.
Dairy contains less tryptophan per serving compared to meat and fish. A 1-cup serving of milk provides 100 milligrams of this amino acid.
5 of the Best Sources of Tyrosine
Low tyrosine levels are rare, but you may need a higher dose during stressful times. Tyrosine is found in a variety of foods, such as meats and cheese. Legumes are the best option for vegans.
The amount of tyrosine you need each day is linked to the essential amino acid precursor phenylalanine—for adults, that is 14 milligrams per kilogram per day.
1. Red Meat
Roast beef, a decadent meal, is undoubtedly one of the best sources of tyrosine. It provides 1,178 milligrams per 3-ounce serving. Pork contains slightly less, typically, around 1044 milligrams in a 3-ounce serving of lean pork chops.
2. Poultry and Fish
Protein options such as salmon, turkey, and chicken contain between 900 to 1,000 milligrams per 3-ounce cooked portion.
Parmesan cheese contains 559 milligrams per ounce.
One egg has 250 milligrams.
A cup of cooked white beans has 450 milligrams of tyrosine.
Bonus: Top Sources of Carnitine and Glutamine
Most animal-based foods contain carnitine. Beef is one of the richest natural sources of carnitine. Lean cuts have 95 milligrams or less of cholesterol and fewer than 10 grams of total fat in every 3-ounce serving. Chicken breast is high in protein, low in fat and cholesterol, and a good source of vitamins and minerals. It also contains 3 to 5 milligrams of carnitine in every 4-ounce serving. All fish and shellfish have some carnitine (cod has the highest concentration of any seafood).
It can be challenging to obtain meaningful levels of supplemental carnitine from a plant-based diet, but it is possible. Dairy is a valuable resource, and some grains and vegetables, like asparagus, also provide carnitine.
While your body normally makes all the glutamine it needs, a severe injury or illness may require you to increase your dietary intake. Meat and seafood top the list when it comes to best sources of glutamine.
Eggs are also rich in glutamine, as are many dairy products. Whey protein, a byproduct of cheese production, is a top source of glutamine. Dried lentils, peas, beans, and cabbage are excellent options for vegetarians and vegans. Many whole grains, including oats and products made from whole wheat, quinoa, millet, and brown rice, are also abundant in glutamine.