10 Days on a Grain Brain Diet

What should a person eat? In recent years, the most sensible answer to that question has been journalist Michael Pollan’s oft-quoted, “Eat food. Not too much. Mostly plants.” Then last fall, David Perlmutter, M.D., a neurologist, published Grain Brain: The Surprising Truth About Wheat, Carbs, and Sugar – Your Brain’s Silent Killers (Little, Brown), a manifesto against carbohydrates that soon topped the New York Times bestseller list.

Annoyingly, the title is a misnomer. If you wish to observe the Perlmutter protocol, you must banish from your diet not just grains but sugar (with the exception of small amounts of dark chocolate), root vegetables, all legumes except lentils, and starchy fruits like bananas, which rate high on the glycemic index. Carb intake is limited to 50 to 80 grams a day—a mere 5% of total daily calories, the equivalent of a serving of fruit. Allowed are grass-fed meats, free-range poultry, fish, leafy greens, nuts, and healthy fats.

While few would dispute that eating masses of carbs isn’t good for anyone, there’s no unequivocal proof that eating small or moderate amounts of grains is harmful.

Just reading the catalogue of maladies that Dr. Perlmutter claims carbs can trigger is sobering enough to put a glutton like me off her feed. Insomnia, anxiety, chronic headaches. Depression, epilepsy, Alzheimer’s disease. “Modern grains,” he writes, “are silently destroying your brain.” Remember that 1980s public ad campaign with the fried egg and the tagline, “This is your brain on drugs?” Dr. Perlmutter says that grains have a similar effect on the brain, a claim he substantiates with references to peer-reviewed studies that link elevated blood sugar (insulin resistance) to Alzheimer’s and also with observations from his own medical practice.

My memory is excellent, knock wood, and I’d like to keep it that way. The prospect of Alzheimer’s disease is particularly scary to me. For this reason, when Grain Brain was released, I picked up a copy and read it in a single evening. But the diet Dr. Perlmutter proposed seemed extreme—no fun at all! And while few would dispute that eating masses of carbs isn’t good for anyone, there’s no unequivocal proof that eating small or moderate amounts of grains is harmful. In fact, a senior editor at The Atlantic, James Hamblin, M.D., recently published a long, lucid post on that magazine’s website in which he argues that Dr. Perlmutter’s theory is a bit too neat.

And yet, and yet. There’s no denying that for some of us, grains and high-carbohydrate foods at the very least lead to overeating. What if Dr. Perlmutter is on to something? What if he’s right to unmask grains and carbs as “a terrorist group that bullies our most precious organ?” With the encouragement of a Rewire Me editor, I decided to try the Grain Brain diet and see for myself. To show I meant business, I vowed to temporarily divest my kitchen of every last grain of rice, every sack of flour, and all my pizza-making paraphernalia. But then the snow came and the ice, and it was no longer possible to haul 50 pounds of high-carbohydrate foods to their designated safe house unless I rented a sled. The Grain Brain is intended to be a permanent lifestyle change, but my ambitions ran to trying it out for 10 days.

The next day, I felt extremely odd. Not bad, just different. It took a while before it dawned on me that for the first time in ages, I wasn’t ravenous.

On the first day of the diet, I felt like crap. I mourned all the nice members of the terrorist cell with whom I had been keeping company as I took my leave of each one. Goodbye avocado on whole grain toast with chili flakes and olive oil; goodbye oven-baked sweet potato fries; goodbye carrot soup; goodbye cornmeal-crusted flounder; goodbye chickpea curry; goodbye dearly beloved sticky dates. Goodbye, goodbye!

Then I stayed up until midnight watching Lidia Bastianich, the Italian chef, instruct her television audience on the proper way to grill bread (always drizzle on the olive oil after grilling, never before). In spite of massive grain consumption, Lidia is sharp as a tack. Could Americans be more prone to grain brain than Italians? I fell asleep but woke up at four in the morning and watched a documentary about rice production in Senegal. A man said, “We Senegalese love rice, but few of the people in my village can afford it.” He spoke beautifully and was very bright. Obviously: He had no access to rice.

While I wouldn’t put my faith in a low-carb diet in the hope of dodging the Alzheimer’s bullet, I feel so much more clear-headed than I did when I started this regimen that I intend to stick with it a little longer.

The next day, I felt extremely odd. Not bad, just different. It took a while before it dawned on me that for the first time in ages, I wasn’t ravenous. My meager vegetarian lunch (I couldn’t stomach the animal protein he agitates for) exploded with flavor! And those colors! They were so intense that I put down my newspaper to take a closer look. On subsequent days, the miracle repeated itself with plain old steamed vegetables. Over the weekend, pressed for time, I deviated from the regimen and scarfed a lentil and rice crepe, and the scale registered a small weight gain (apparently, weight loss is a fringe benefit of the diet). One thing led to another, and soon the forbidden sweets in my cupboard beckoned. On my way to the kitchen, I stopped to check email and found a note from my editor: How is the Grain Brain thing going? Shame-faced, I put on my running shoes and went to the gym. I haven’t been tempted by cookies, cakes, or any other sweet things since that moment.

As I approached the tenth day of the experiment, I came across a fascinating article in the Guardian about the difference between liking food and wanting food. It seems that neuroscientists have determined that sugar sensitizes the brain’s reward system so that long after you’ve kicked the habit, the mere sight of something sweet can trigger what’s called a “hyperactive dopamine response.” You might not even derive pleasure from eating a food you crave but feel compelled to bolt it down anyway.

While I wouldn’t put my faith in a low-carb diet in the hope of dodging the Alzheimer’s bullet, I feel so much more clear-headed than I did when I started this regimen that I intend to stick with it a little longer. And now I really should do something about those sticky toffee puddings lurking in my fridge.