Are Grains Killing Your Brain?

A new book argues that eating wheat sets you up for Alzheimer's and other brain diseases. Should you go grain-free? Nutrition Diva reviews the evidence behind this latest theory.

Monica Reinagel, MS, LD/N, CNS
4-minute read
Episode #255

In his new book, Grain Brain, David Perlmutter argues that a diet high in grains (especially modern wheat) may be a hidden cause of Alzheimer's, dementia, migraines, and ADHD. In fact, he's convinced that these conditions are primarily driven by dietary choices and that you can prevent or reverse them all by following his program.

Those are some pretty big promises. So I thought it would be worth checking out the evidence to support them.>

Did Cavemen Get Alzheimer's?

Perlmutter starts out with a familiar Paleo refrain: Our digestive systems are not adapted to grains, which entered the human diet roughly 10,000 years ago. According to this theory, any food that wasn't part of the human diet then is potentially toxic. This makes it sound as if the Paleolithic Era were a sort of magical moment in history when the human body was perfectly adapted to its environment. But that's kind of silly when you think about it.

See also: Pros and Cons of the Paleo Diet


Just like us, our Paleolithic ancestors had certain genetic traits that worked to their advantage, others that slowed them down, and still others that were (at the moment) neither helpful nor harmful. And just like us, Paleolithic humans didn't all have the same genetic traits and didn't all live in the same environments or have the same diets. 

Is Modern Wheat the Real Problem?

Apparently, eating grains didn't actually cause too much trouble for the first 9900 years that they were part of the human diet. 

But the whole Paleo debate is really moot because, as soon as Perlmutter lays out this argument, he abandons it for a different, conflicting argument - one that you'll recognize if you read William Davis' book Wheat Belly.  Apparently, eating grains didn't actually cause too much trouble for the first 9,900 years that they were part of the human diet. But now, modern strains of wheat, which are higher in gluten, are causing widespread health problems. Davis points out that the rise in obesity and diabetes in the 20th century parallels the increasing use of these modern strains.  Similarly, Perlmutter observes that Alzheimer's, migraine, ADHD, and other neurological ailments have increased over the last century. 

Now, of course, the fact that two things occurred at the same time doesn't mean that one caused the other. The increase in Alzheimer's and dementia could also be explained by improved detection and diagnosis, dramatically increased life expectancy, or any other aspect of our diet and lifestyle that has changed over the last 100 years...which is to say, all of them. But not to worry: It turns out that modern wheat is only part of the problem...

More than Grains Are at Work on Our Brains

Perlmutter goes on to explain that anything that leads to chronically high blood sugar and/or inflammation, can hurt your brain. That list, of course, includes sugar, fruit, grains, trans fats, low-fat diets, smoking, sedentary lifestyle, obesity, stress, and inadequate sleep. 

Frankly, it's a lot easier for me to buy the idea that neurological disease is caused by a complex interaction of diet, genetics, environment, and lifestyle choices than it is to buy the idea that one food or food group is killing our brains. 

Ironically, the program Perlmutter ultimately lays out is not even grain-free! He allows gluten-free grains such as amaranth, rice, millet, buckwheat and quinoa in moderation.  His plan, is, however, very low in carbohydrates and very high in fats. He also stresses the importance of sleep, exercise, and other healthy lifestyle habits. 

Does Perlmutter's Program Work? 

OK, so maybe the title Grain Brain is a bit of an over-simplification. That happens in publishing sometimes.  The real question is whether Perlmutter's program can deliver on his big promise: freedom from migraines, fatigue, ADHD, moodiness, and protection against dementia and Alzheimer's disease?

If you suffer from frequent headaches or other chronic malaise, it might be worth trying.

Regarding headaches and fatigue, the evidence for this program is largely anecdotal. Perlmutter writes of patients who had dramatic improvement from chronic headaches as well as vaguer symptoms like "spaciness."  And if you suffer from frequent headaches or other chronic malaise, it might be worth trying. If you get relief, who cares whether anyone has done a placebo-controlled trial - or whether eliminating wheat was the key to the program's effectiveness?

See also: Are Grains to Blame?


But what if you feel just fine now and just want to reduce your risk of Alzheimer's disease in the future? Unfortunately, there isn't a lot of evidence that this approach will prevent these diseases. In fact, there is some evidence to the contrary.  We have long-term data, for example, linking the Mediterranean diet (which is neither low carb nor wheat-free) with reduced rates of dementia. People who follow the DASH diet (which is pretty much the exact opposite of Perlmutter's program) also have reduced risk.  Unfortunately, data on Alzheimer's in cavemen is pretty spare. 

All kidding aside, I wish we knew exactly how to prevent Alzheimer's disease. I'm not saying that Perlmutter's idea is wrong. I'm just saying that it's unproven.  

Can You Eat Grains and Be Healthy?

So, where does all this leave us with grains? Pretty much where we started. Here are 4 tips that you've heard from me before:

1. If you don't want to eat grains, you don't have to. Just make sure you're covering those nutritional bases.

See also: Are Grains Really Necessary for a Healthy Diet?


2. If you do eat grains, eat them in moderation. This applies to whole grains as well.

See also: The Truth About Whole Grains


3. Enjoy a variety of grains.

See also: How Important is a Varied Diet?


4. Don't forget about the rest of your plate. I think it's overly simplistic to pin a complex disease process on one food or ingredient. Regardless of whether you eat grains or avoid them, what's on the rest of your plate still matters.

What do you think of this topic? Join the conversation on Nutrition Diva's Facebook page or post a comment below.

Grains and brain foods images courtesy of Shutterstock.

About the Author

Monica Reinagel, MS, LD/N, CNS

Monica Reinagel is a board-certified licensed nutritionist, author, and the creator of one of iTunes' most highly ranked health and fitness podcasts. Her advice is regularly featured on the TODAY show, Dr. Oz, NPR, and in the nation's leading newspapers, magazines, and websites. Do you have a nutrition question? Call the Nutrition Diva listener line at 443-961-6206. Your question could be featured on the show.