Is a Diverse Diet Key to Brain Development?

 By Jessica Albrecht-Schultz, WATG Board Member

We have all heard the old adage “you are what you eat,” but does that apply to your brain as well as your body?  Can a diverse diet play a role in your child’s neurocognitive development?

Diverse diet in the evolution of the human brain
First, let us review some human evolution to see how our big brains came to be.

Between 1.9 and 2 million years ago, the brain size of our human ancestors increased dramatically.  Stephanie Pappas, in her article Ancient Brainfood Helped Humans Get Smart, discusses how bone fragments and fossils from various animals  found in northern Kenya during this time period adds evidence to a theory that these pre-humans owed this brainpower boost to fish.  The Omega-3 fatty acids found in the fish could have provided the nutrients the hominins needed to evolve larger brains.  The Proceedings of the National Academy of Sciences journal published a study that also revealed a huge variety in the hominids’ diets.  Aquatic animals are believed to be part of early hominid diet and likely helped with the evolution of large brains, but it may have been the diversity of diet rather than single food groups that pushed hominid evolution forward. [1]

Our ancestors had seasons of abundance and those of hardship due to Nature’s relentless cycles.  When fish, meat and fruit were scarce, our ancestors relied on whatever was available, which oftentimes was not much more than plants, nuts and seeds, tubers, wild grains, and bugs. [2]  They ate what they could get their hands on which led to a diverse diet. 

According to the “cooking hypothesis,” the advent of cooked food again altered the course of human evolution. By providing our forebears with a more energy-dense and easy-to-digest diet, it allowed our brains to again grow bigger. [3] 

Eating better made our ancestors smarter, and being smarter now allowed them to feed themselves more efficiently.  Little by little, as the brain grew larger, man grew taller… eye-hand coordination improved, and planning skills became more sophisticated… allowing for better hunting techniques to catch bigger and… fresher game.  This high-quality diet further increased our ancestors’ fat consumption and available energy, which proved crucial for this rapid brain evolution of Homo erectus. [4]

In Kelly Brogan’s book, A Mind of Your Own, she argues that carbs as well as fish have been key to human evolution.  She says there’s no way we could have developed such big brains had it not been for our access to carbs, in addition to high-quality protein.  Carb consumption, particularly in the form of starch from tubers, seeds, fruits, and nuts was the key to the rapid growth and development of our brains over the last million years. [5]

If a diverse diet is thought to be crucial to brain growth and development, humans should have a very diverse diet today as we have the easiest access to a variety of food in history.  Simply go to the grocery store at any point during the year and you can get high-quality foods such as fresh wild fish, grass-fed animal protein, local and exotic organic fruits and vegetables, and any type of grain, nut, or seed.  Over 300,000 foods and beverages are available with 30,000 to 40,000 available at supermarkets; [6] however not all are considered healthy.  Diversity in our diet is available to us, but the typical American diet is less diverse than ever.  The majority of foods in grocery stores are processed forms of commodity crops, mainly corn, soybeans, and wheat, none of which are sold in their original form from nature, and are often high in sugar, manipulated fats, refined salt and chemical preservatives.  Still, the availability of whole foods, in a state similar to how they are found in nature, are more available to us than ever before.  Naturalists regard biodiversity as a measure of a landscape’s health. [7]  Should diversity at our local supermarket be a measure of our physical and mental health?  I believe it can be, but only if we consume that diversity as nature intended.
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… humans can live just about anywhere on earth, and when their familiar foods are in short supply, there’s always another they can try.  Indeed, there is probably not a nutrient source on earth that is not eaten by some human somewhere – bugs, worms, dirt, fungi, lichens, seaweed, rotten fish, the roots, shoots, stems, bark, buds, flowers, seeds, and fruits of plants; every imaginable part of every imaginable animal, not to mention haggis, granola, and Chicken McNuggets.  The deeper mystery, only partly explained by neophobia, is why any given human group will eat so few of the numberless nutrients available to it. [8]

Food sciences today
Nutrition science is a relatively new science.  It began less than two hundred years ago and is today approximately where surgery was in the year 1650. [9]  There have been some interesting and beneficial findings, but there is much confusion around which foods and nutrients are good or bad for you.  New studies contradict the findings of earlier studies.  As is the case for all scientific studies, the results depend on a vast number of factors.  In the case of nutrition, whomever funds the study, the expected results, the interpretation of the data and what is chosen to be highlighted from the study all influence the published findings.  The ramification is confusion and inconsistency.   Additionally, food trends are a darling of the media, and we are bombarded with information about new superfoods, foods to avoid and fad diets, all adding to the confusion.  Diversity of whole foods in our diets steer us away from this confusion.  Nature has given us a plethora of foods that humans can eat.

Neuro-nutrition, or how food affects the brain, is even younger.  Nutritional requirements for the brain may be substantially different than requirements for other organs of the body.  Diversity is believed to be key for neuro-nutrition.  However, in looking at food and its specific relationship to the brain, we may be trying to isolate something that is meant to function as a whole.  A lot of research is being done with a holistic view of the mind-body connection and the gut-brain connection.   

Nutritional psychiatry is a newly recognized but growing field.  This discipline focuses on how the use of food and supplements can be used as treatments for mental health disorders.  According to Eva Selhub, MD in her article Nutritional psychiatry: Your brain on food, this field is finding that there are many consequences and correlations between not only what you eat, how you feel, and how you ultimately behave, but also the kinds of bacteria that live in your gut.  Microbiota in the gut and the beneficial bacteria that live in it are being studied for the impact on your immune system and various medical conditions.

What to eat
Whole foods, those of which are unprocessed and typically found in the outer aisles of the supermarket, are the best brain foods and are also good for our bodies.  

Food that contains polyunsaturated fat which has Omega-3 fatty acids are known to be necessary for healthy brain function.  These foods have been studied to reduce the risk of Alzheimer’s and memory loss, and contain the fat that our brains in large part are made of.  Omega-3s are found in fish and shellfish and have higher concentrations in wild-caught than farm raised fish.   The same is true for wild game and grass-fed beef, compared to their conventional counterparts.  I find it extremely interesting that walnuts look like a brain and are the top nuts to eat for brain health.  But don’t limit your nut consumption to walnuts just because they have a high concentration of Omega-3s.  All nuts and seeds, in general, are good for the brain due to their rich sources of fatty acids and antioxidants.

Eggs contain nutrients such as choline, which is used by the brain to memorize information and learn from experience.  Of all the animal foods available to us, eggs are hard to beat for brain nutrition.  To continue your diverse diet, try as many types of eggs as you can find.  I’ve found chicken, duck and quail eggs at my local supermarkets.  In addition, friends who have geese,  guinea hens, and pheasants have given me some of their eggs for my family’s meals.

Whole grains slowly release glucose in your bloodstream, which helps with concentration and focus.  They also work to reduce inflammation in the brain, potentially preserving your memory.    Ancient grains, such as einkorn, emmer, amaranth, millet, quinoa, black rice, black barley, and spelt, can be found at the supermarket, or are now easily ordered online.  These ancient grains are nutritionally superior to modern grains like wheat, corn and rice.

Phytochemicals found in fruits and vegetables are powerful to protect our health and promote healing, but also work specifically in the brain to improve memory and learning.  Over 8,000 phytochemicals exist, [10] again advocating for diversity in our diet.  Nutritional science has started to figure out the synergistic effects of combining certain foods, but much is still unknown.  Our ancestors may have figured out these synergies intuitively or by trial-and-error without having the science to help them.  This synergistic knowledge of what types of foods to combine with each other in a meal has been passed down from generation to generation, and may have been lost in part when America’s fore-families moved away from their homelands and thus lost their generational food knowledge.
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It is my belief that incorporating as many types of whole foods as possible into your family’s diet is key to a healthy, strong, and clear brain in which new synapses are able to form, allowing for deeper and more complex thought. This diet provides more nutrients than a low quality, uniform diet.

Diverse for diversity
Not only is a diverse diet likely beneficial for brain growth and development, expanding the variety of food offered to your children, and encouraging enjoyment of dishes from various cultures is also a good way for us to demonstrate racial, ethnic and cultural diversity.  Voicing opinions about diversity is common in 2020, but feeding our children dishes from many cultures is a small, but important way that our actions will help our children be tolerant and understanding of the diversity in the world in which we live.  It’s actually food for thought, as they say.
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About me
​I’m a mom of two gifted kids.  I spend most of my time volunteering at my children’s school, for their extracurricular activities, and advocating for educational opportunities that will lead to their academic growth.   Food, however, is my passion.  I love to cook for my family and friends, discover new restaurants, collect and study cookbooks, grocery shop for the best available ingredients and learn about food history, culture, and policy.  This article is meant to get the GT community thinking more about the link between our diets and our brains.  Many of the ideas have, or could have, entire books devoted to them.  It is not meant to be comprehensive, and I am not a food nutritionist or neuroscientist.  I’m just a mom trying to do what I think is best for my family, like so many moms and dads out there.  I’m happy to receive constructive feedback, but please keep it positive. 
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[1] Stephanie Pappas, Ancient 'Brain Food' Helped Humans Get Smart   June 03, 2010
[2] Dr. Lisa Mosconi, Brain Food: The Surprising Science of Eating for Cognitive Power
[3] Michael Pollan, Cooked:  A Natural History of Transformation
[4] Mosconi, Brain Food   
[5] Kelly Brogan M.D., A Mind of Your Own:  The Truth About Depression and How Women Can Heal Their Bodies and Reclaim Their Lives
[6] Bill Code, Karen D. Johnson M.D., and Teri Jaklin, Solving the Brain Puzzle:  A Complete Layperson’s Guide to Achieving Brain Health
[7]  Michael Pollan, The Omnivore’s Dilemma
[8] Pollan, The Omnivore’s Dilemma
[9] Michael Pollan, Food Rules:  An Eater’s Manual
[10} Code, Johnson and Jaklin, Solving the Brain Puzzle