Dr. David Perlmutter’s famous book Grain Brain claims that carbs, sugars, and even ‘healthy’ grains like wheat are bad for your brain health. Is this really the case?

In his revolutionary and controversial book Grain Brain, Dr. David Perlmutter dresses up grain in a villain’s mask and cape and blames it for increasingly common diseases like dementia and Parkinson’s disease.

Going against the “grain,” Dr. Perlmutter asserts: “The origin of brain disease is in many cases predominantly dietary … to a large extent numerous neurological afflictions often reflect the mistake of consuming too many carbs and too few healthy fats.”

But is grain really the villain, or has Dr. Perlmutter turned it into the real-life Red Herring? Well gang, you can hop into the retro Mystery Machine and drive across the nation to find the villain, or you can read this comprehensive evaluation of the Grain Brain diet.

Overview and history of the Grain Brain diet

Although the gluten protein is one of the most commonly consumed proteins around the world, doctors William Davis (author of the worldwide bestseller Wheat Belly) and David Perlmutter have led the revolt against gluten—and grains in general.

Davis contends that grains that are considered by many to be healthy are destructive, and the Wheat Belly diet he recommends is a reflection of this outlook. Perlmutter goes even further, arguing that genetically-modified wheat is a “modern poison.”

The anti-gluten, anti-grain crusade is a relatively new phenomenon. Just a decade ago, it was only diagnosed Celiacs (about 1 percent of the population) who avoided gluten, but now at least one-third of Americans are trying to restrict or eliminate gluten consumption.

Many of these people believe that gluten consumption causes digestive distress, and the term “non-Celiac gluten sensitivity” was invented to describe this phenomenon.

But going from gluten-free to grain-free is a big step. Both Perlmutter and Davis believe it is a necessary step if your goal is overall health. And people are buying this idea; in the form of book sales—both Davis and Perlmutter’s books have generated quite a bit of revenue.

It’s amazing that such a restrictive diet is becoming so popular. And Perlmutter not only recommends gluten and grain-free diet, but also a diet low in sugar and processed foods.

But not everybody agrees. In early 2017, Dr. John Douillard issued a rebuttal in the form of his book Eat Wheat. According to Douillard, it is not wheat (or even dairy) that is the problem (i.e., the cause of inflammation and disease). After all, humans have been eating grains for 3.4 million years.

Rather, it is a clogged lymphatic system that causes people to be overly sensitive to certain foods, like wheat and other grains. In his book, he details a plan to unclog the lymphatic system to allow for a free flow of waste, toxins, and dead tissue as well as proper elimination.

Dr. Perlmutter contests this idea, arguing that it is the grain itself that leads to disease. Humans have simply not evolved to properly digest grain. In his own line of work as a neurologist, he has seen the utter transformation of his patients who once suffered with brain fog, dementia, and obesity.

While medication did little to solve their problems, a grain-free diet worked wonders. Because of his anecdotal experience as a doctor, he firmly believes in his diet plan—and so do many others.

Here is an extremely informative video debate between both Dr. Perlmutter and Dr. Douillard in which they discuss their research and points of view in the “to eat or not to eat wheat” debate:

Main purpose and goal of the Grain Brain diet

Dr. Perlmutter’s aim is to boost the body’s wellness by improving brain health through proper nutrition. Rates of dementia, specifically Alzheimer’s Disease, an autoimmune disease characterized by protein misfolding in the brain, are rising.

In fact, as high as ten percent of adults over age 65 have Alzheimer’s, and one in three seniors dies with a dementia of one form or another.

It is a debilitating condition; not only is it heart-wrenching for the victim and his or her family, but also costly for insurance companies. It is expected that by the year 2050, over 16 million Americans may have Alzheimer’s.

Perhaps dementia dread is the reason that Dr. Perlmutter’s diet has become so popular. Perlmutter promotes his Anti-Alzheimer’s Trio (avocados, grass-feed beef, and coconut oil) as a means to support brain function, since the brain is entirely made of fat. For this reason, he believes that low-fat diets devastate the brain.

But even so, not everyone agrees that the Grain Brain diet accomplishes its stated goals. Detractors like Dr. John McDougall argue that the Grain Brain diet may actually cause health problems, just like the low-carb Atkins diet.

Comparing the two diets, McDougall laments that both emphasize reducing carbs and increasing animal product consumption to unhealthy levels.

According to McDougall:

“Within [Grain Brain and Wheat Belly] you learn that all starchy foods, including rice, corn, and potatoes—the traditional foods consumed by billions of people throughout human history—are now unhealthy and must be minimized or, better yet, avoided altogether. If you believe [Perlmutter and Davis], then what is left to eat in order to meet your energy requirements? Meat, dairy, fish, and eggs (the original Atkins Diet).”

McDougall further argues that to create their dietary protocols, Davis and Perlmutter must “have had to ignore the bulk of science, exaggerate the truth, and make false associations.” Wow—harsh critic!

But McDougall is leaving out a really important group of foods: other plant-products. Sure, science says that eating a diet rich in animal products is unhealthy, but Perlmutter himself advocates a diet rich in plant-based foods. No, he doesn’t want people to eat grains, but pretty much everything else is on Perlmutter’s table when it comes to plants!

Who is the Grain Brain diet ideal for?

According to Perlmutter, this diet is designed for everyone, because with toxin exposure and genetic modification of food on the rise, anyone is susceptible to developing a debilitating brain disease. But specifically, the Grain Brain diet is for those with a family history of brain disease.

Scientists like Perlmutter also state that environmental influences, like nutrition, play a role in genetic expression. In his book, Perlmutter avoids the topic of individual dietary needs (nutrigenetics), insisting that everyone can benefit from a low-carb, no-grain, low-sugar, high-fat diet.

Clearly, he intends to include all demographics in his “universal” diet plan.

Is the Grain Brain diet easy to do?

The Grain Brain diet is definitely not the easiest of diets to follow. Like the paleo diet, this eating plan eliminates all preservative-filled, processed foods, artificial sugars, grains, and gluten. Unlike the paleo diet, the Grain Brain diet recommends certain foods that specifically promote brain health.

According to Perlmutter, on-the-go moments are the toughest on the Grain Brain diet. Because all food must be natural and unprocessed, there are no easy grab-and-go snacks. Just like paleo followers, anyone on the Grain Brain diet must plan ahead for all meals of the day.

Not only that, but many people become confused on the Grain Brain diet, believing that they should avoid all starchy vegetables. Instead, they overconsume animal products.

But consuming starchy vegetables is a necessity on this diet because, even though it is low-carb, you have to have some carbs in your diet to survive and thrive; and your carb source can’t be grains—even though grains are a staple in the traditional Western diet.

As you replace grains with healthy fats, you should aim to achieve ketosis. According to Perlmutter in his blog post discussing ketosis, “ketones are a special type of fat that can stimulate the pathways that enhance the growth of new neural networks in the brain.”

Diets extremely high in fat and extremely low in carbs encourage the body to produce more ketones. It is very difficult to achieve ketosis, and you must measure your ketone level by using urine strips.

Not only that, but you will likely face backlash from mainstream doctors if your goal is to achieve ketosis because it is not widely recognized as being healthy. In fact, many doctors believe that it is a sign of muscle breakdown.

To fully adopt the Grain Brain diet, you have to be willing to make sacrifices and stray far from the mainstream American diet. It is not easy to do, and you must be fully committed. Grain Brain is not an easy diet, and it is not something you can do half-heartedly.

You must exercise extreme self-control, and to do that, Perlmutter has this encouraging (?) word of advice:

“If you cannot control your hunger and appetite, good luck managing your blood chemistry, metabolism, waistline, and, in the bigger picture, the prospect of crippling your brain.”

Those are some harsh, eye-opening words; Perlmutter certainly writes with passion and conviction!

Foods that are part of the Grain Brain diet

At the beginning of the diet, there is an optional fast to rid the body of toxins and increase metabolic efficiency. After that, the basic principles of the Grain Brain diet are:

1. Eat healthy sources of fat
2. Reduce carb intake
3. Eliminate added sugars and reduce natural sugar intake
4. Eliminate processed foods

Foods that Perlmutter highly recommends are:

1. Healthy fats like olive oil, coconut oil, avocados, sesame oil, nut butter, and butter from grass-fed cows
2. Grass-fed beef and other humanely raised meats
3. Full-fat cheese
4. Grass-fed tallow
5. Almond milk
6. Raw, unsalted nuts
7. Nut flour
8. Anything from a coconut
9. Seeds
10. Whole eggs
11. Wild-caught fish
12. Green leafy veggies and other non-starchy veggies
13. Low-sugar fruits
14. Herbs
15. Tea and coffee (Perlmutter believes that coffee drives brain health)
16. Purified water

You can consume as much of these foods as you would like. Pay special attention to the Anti-Alzheimer’s Trio: avocados, grass-fed beef, and coconut oil.

grain brain diet review avocado

Healthy fats like avocados are essential for better brain health, according to Dr. Perlmutter.

Foods to consume in moderation include:

1. Moderately starchy vegetables like carrots and parsnips
2. Legumes
3. Dark chocolate
4. High-sugar fruit—but not more than one per day
5. Wine—only one glass per day

Grain Brain goes beyond food; it is a lifestyle. Perlmutter emphasizes the importance of exercise when he wrote, “the simple act of moving your body will do more for your brain than any riddle, math equation, mystery book, or even thinking itself.”

Foods that are to be avoided on the Grain Brain diet

This is the heart of the Grain Brain diet. You may notice that the foods on this list are similar to foods banned on the paleo diet.

Paleo and Grain Brain have a lot of overlapping concepts, but the main difference is that Grain Brain is focused on brain health. And unlike paleo, there are no “cheat days” on Grain Brain!

Here is what you should avoid on the Grain Brain diet:

1. Low-fat dairy products (they should all be full-fat)
2. Any other alcoholic beverages besides wine
3. Any grains (especially gluten-containing grains)
4. Processed meats
5. Processed, packaged foods (even if they are gluten-free)
6. Pastries and baked goods
7. Condiments with gluten in disguise
8. Corn
9. Potatoes
10. Soy
11. Fruit juices
12. Fried foods
13. Fat-free and low-fat foods (these have been denatured)
14. Chips, crackers, and cookies
15. Sweeteners

How effective is the Grain Brain diet overall?

Our high rating is based primarily on anecdotal evidence, as well as research studies that confirm the health benefits of coconut oil and plant-based diets. Because the Grain Brain diet is relatively new (2013), there has yet to be a large-scale study to confirm the purported health benefits of this diet.

But, because it is similar to the paleo diet (with a slightly different focus), we can assume that some of the benefits of the paleo diet (i.e., increased energy levels, improved cardiovascular health, weight loss, etc.) are the same for the Grain Brain diet.

Potential mistakes to avoid on the Grain Brain diet

If you decide to try the Grain Brain diet, avoid these common pitfalls:

1. Eating too little fiber (prebiotics)

Perlmutter designed his diet around the idea that low-carb is the best. However, this can lead to insufficient fiber consumption. Fiber is important for digestive health and microbiome balance. That is, prebiotics from fiber feed the beneficial bacteria in your intestines. Make sure you do not completely eliminate starchy vegetables from your diet, or else these bacteria might starve!

2. Eating too many animal products

Animal products can be pro-inflammatory. Study after study has found that plant-based diets are much healthier than animal-based diets. Not to mention that they are better for the environment because plants require less energy to grow than animals. Be sure you do as Perlmutter recommends and eat a wide variety of plants.

3. Eat too much red meat

Out of all types of animal meat, red meat is the most inflammatory. Not only is it difficult to digest, but if you have leaky gut and undigested meat particles leak into your bloodstream, it can cause chronic bodily inflammation. And chronic inflammation is at the root of all disease. Do yourself a favor and eat red meat sparingly, despite Perlmutter’s urging.

How healthy is the Grain Brain diet?

While eliminating gluten, processed food, and artificial sugar from the diet is beneficial, some components of this diet have the potential to be unhealthy.

Particularly, the idea that people should achieve ketosis on their own (without a doctor’s advice or consent) is troubling because it might signify muscle deterioration.

In addition, the complete elimination of all grains as well as the reduction of starchy vegetable consumption is alarming. After all, people need to consume at least a basic level of carbohydrates for overall well-being!

Finally, the recommendation to consume red meat liberally to promote brain health flies in the face of research that demonstrates that consuming high amounts of red meat is pro-inflammatory.

As with most other kinds of food, it’s probably all right to have red meat every so often but just don’t go overboard and start eating several slabs of steak every meal!

Perlmutter’s Grain Brain diet may not be Red Herring, but if you choose to follow this diet, beware of some ghastly, ghoulish traps!

Our Grain Brain diet review conclusion

Regardless of what critics may say about the Grain Brain diet, there’s no arguing that a lot of people who have gone on this eating plan have reported better clarity, focus, and an overall sense of well-being.

While there is yet to be conclusive evidence (in the form of large scale scientific studies) about whether the Grain Brain diet accomplishes its goals, there is evidence that specific aspects of the diet, like its emphasis on coconut oil and other plant-based foods, are healthful.

If you think you would benefit from implementing the Grain Brain diet as a long term solution to improve your mental and physical health, we recommend you read the original Grain Brain book as well as Dr. Perlmutter’s The Grain Brain Whole Life Plan.

The book contains a practical and comprehensive program to help improve your brain health as well as help you lose weight, relieve chronic conditions, and rejuvenate your body.

It also goes deeper into Dr. Perlmutter’s work on brain health and provides a wide range of strategies, recipes, meal plans, and smart advice on how you can improve every aspect of your life with the principles of Grain Brain.