Grain Brain & The Interaction Between Diet & Genes

Grain Brain & The Interaction Between Diet & Genes

7 minute read

The food we eat is far more than just vitamins, minerals, macronutrients, and energy. Our body tissues are composed of food––we literally are what we eat. It's why terms like "grain brain" and "wheat belly,"  exist. It's why people who fast regularly tend to have brighter eyes, a stronger immune system, and more efficient digestion. It's why a high-fat diet like the ketogenic diet can support healthier and higher brain functioning.

We don't just eat to feed the beast, like the way fuel serves an automobile. Food affects every cell in the human body. Each cell contains an incredible amount of information that informs our everyday experience on every level––physically, emotionally, mentally, energetically, and spiritually.

Knowing that, doesn't it make sense to choose the most optimal diet that will provide the best living experience possible? Obviously that's a rhetorical question!

But let's take it a step further––we also become what we eat. What that means is that our diet affects our genes.

grain and its factor in dna

How Food Impacts Your DNA

The human body contains about 20 to 25 genes. Each one of us has a distinct genetic profile that remains consistent throughout our lives. However, how those genes are expressed changes in response to all manner of environmental influences: stress, diet, water, exercise, and more. Epigenetics is a branch of science that studies the impact of the environment on gene expression. Where diet is concerned, it gets even more specific. Nutrigenomics examines the interaction between nutrition and genes and how the human body responds to specific nutrients.

The fascinating part about this branch of knowledge lies in the individual experience. Each person has a unique genetic profile that influences how the body detoxifies, its propensity toward inflammation, quality of mood, and determines what diets are optimal or harmful. That means one way of eating rarely works for everyone. Not only that but different nutrients and classifications of foods, such as meat and dairy or grains, impact different people in unique ways. And that impact evolves throughout our lives.

For example, at one time in your life, you might have been able to tolerate dairy, but roll on a few years and even a small wedge of gouda gets your stomach in knots. It's why we must continually reassess our diets through conscious eating and attention to how those foods impact us physically and energetically.

Our genes have evolved over thousands of years, and they continue to change in response to the environment. Each gene is encoded with information that determines how well we use different nutrients, including the starches, sugars, and fiber found in grains. But beyond ancestral data contained in human genes is unique information specific to each person that controls how our individual bodies store and burn nutrients.

Fascinating, right? At the level of our genes, each one of us really is a special snowflake!

But all jokes aside, this knowledge means that we can only take diet advice as one piece of the puzzle in discovering what foods are best for us as individuals, what nutrients we should supplement, and the types of foods we should avoid. Because our bodies, the environment, and nutritional research are constantly evolving, an answer today prompts more questions tomorrow. It's a never-ending journey of continuous discovery!

Your Brain on Grains

The main macronutrient in grains is carbohydrates, and they're why people on a weight loss journey tend to limit their grain intake. Carbs contain fiber (disaccharides), sugar (monosaccharides), and starches (polysaccharides). We need all three nutrients for optimal functioning.

But of course, knowing what we do about individual genes and their expression helps us realize that we don't need them in the same quantities, person to person. For example, some people require more animal fats or plant fiber or even starches, depending on their unique genetic profile. (How do you know? You can get a gene test like 23andMe to get a rudimentary understanding of your genes to develop a more optimal, personalized diet––see #3 in our references section for more information).

We can't discount that even though it will manifest differently depending on the person, some classifications of nutrients have a generalized effect on the human body.

Over thousands of years, human genes have evolved to accommodate a diet high in fat and low in carbs. But a quick look at the standard American diet (also known as SAD) clearly reflects just the opposite. We're loading up on sugars and starches and the wrong kinds of fat. That means we're working against our bodies, rather than with them. Florida-based neurologist David Perlmutter explains that we need to assume a more ancestral diet, comprising about 75% fat and 5% carbs. Today, the average person consumes about 60% carbs and 20% fat, with protein consumption remaining about the same (1).

Many of us experience the negative impacts of excess carbs within a few days of eating a carb-loaded diet––a noticeable increase in belly fat. But what you might not have noticed is the impact on your brain.

Dietary sugar found in carbohydrates has negative neurological consequences, a premise that Perlmutter makes in his book Grain Brain. He includes information from a growing body of research that surmises Alzheimer's is a third type of diabetes. While this may be an insightful bit of information, it is not all that surprising if we look in general to the interaction between lifestyle, which includes diet and mental health. Such findings suggest that we can reduce the risk of debilitating age-related psychological disorders, such as dementia and Alzheimer's, by optimizing our diet.

The results of a study published in the Journal of Alzheimer's Disease reveal that people aged 70+ who consume high-carb diets are almost four times more likely to develop a mild cognitive impairment, especially when that diet is high in sugar. A diet higher in protein and fat relative to carbs may reduce this risk (2). However, we need to consider the cardiovascular risks of a high-fat diet too, especially one composed primarily of saturated animal fat.

Rosebud Roberts, a Mayo Clinic epidemiologist states, "a high carbohydrate intake could be bad for you because carbohydrates impact your glucose and insulin metabolism… sugar fuels the brain, so moderate intake is good. However, high levels of sugar may actually prevent the brain from using the sugar, similar to what we see with type 2 diabetes"(2).

Learn, Eat & Listen

There's a lot of information out there, and it's often downright confusing. How do we determine what to eat and what to avoid?

From one experimenter and investigator to another, our advice is this: Learn, eat, and listen to your body. Consume all information with a grain of salt (but choose a high-quality one!). Be critical of what you read and hear. Practice moderation with all food––even the known nutritious ones, like fresh vegetables. When you eat, notice how your body responds on a physical, mental, and energetic level. That means entering each meal time with conscious awareness of the act and impact of eating. It's one thing to know that broccoli is good for the body, and another to experience that it's good for your body based on how you feel during and after eating it. And if broccoli is indeed good for you, that doesn't mean you should eat it every day at the expense of other important nutrients.

Want to know more about what grains to include in your diet? Check out another one of our recent articles, The 5 Most Nutritious Grains.

From our kitchen to yours, we wish you a balance of nutrients on every plate––including grains!


  1. David Perlmutter (2013). Grain Brain: The Surprising Truth about Wheat, Carbs, and Sugar--Your Brain's Silent Killers

  2. Eating Lots of Carbs, Sugar May Raise Risk of Cognitive Impairment, Mayo Clinic Study Finds

  3. 23andMe: DNA Genetic Testing & Analysis

  4. Data Driven Health Radio Podcast. Personalizing the Keto Diet Based on Your Genetics - Sarah Morgan.

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