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In my twenties, I once fell asleep at noon after eating a bagel, though there was no reason to be tired. I'd often be fuzzy-headed after a meal.
"Brain-fog" is a common sign of celiac, an auto-immune reaction, and of other kinds of sensitivity to gluten, a protein in wheat and rye.
Claire Baker, who now works for the advocacy group, Beyond Celiac, was afflicted with "brain fog" before she received her own celiac diagnosis. She was a program director at another major nonprofit and the fuzziness was affecting her productivity. "I thought there was something terribly wrong with me — couldn't concentrate. I had no idea the problem was related to my diet, and no clue that it could be a symptom of an undiagnosed disease," she told me.
In a new survey of patients with either celiac or gluten sensitivity, more than 70 percent said they had trouble concentrating after eating gluten. Nearly 60 percent of celiac patients (and nearly 70 percent of those with gluten sensitivity) said they became groggy. About a fifth said the symptoms showed up within a half-hour to an hour, but similar portions experienced the symptoms within the next four hours, or between one and two days later. The symptoms typically lasted a day or more.
So if you're having trouble at work after your bagel or muffin breakfast and your sandwich at lunch, experiment with eating other foods that don't contain gluten.
Food intolerances can also make you anxious and are linked to headaches and depression.
If you find that you can link your symptoms to gluten, don't just go gluten-free on your own. You should get tested for celiac, a serious illness that requires monitoring. Even if you don't have celiac, you may need help figuring out your diet. Many people get some improvement when they cut out gluten but find that other foods bother them as well. You might need to be extra careful with traditional "gassy" foods like beans and dairy.
If gluten triggers an inflammatory response, it can affect any system in your body — from your skin, to your nerves, to your brain.
One man I'll call Tony had trouble with compulsive twitches and tics for years. The neurologists he saw couldn't find a clear cause. One said, "This is the way God made you."
He also was prone to becoming enraged at small irritations — for example, a dinner companion eating with her mouth open.
Both the tics and the irritability dropped dramatically when he cut gluten out of his diet.
Your primary care doctor may dismiss your interest in gluten — after all, it's clear that "going gluten-free" has become fashionable.
Not everyone who goes gluten-free really needs to.
But you might.
Truly cutting gluten from your diet requires attention — you need to read labels on any packaged food and ask lots of questions in restaurants. Any Chinese restaurant meal with soy sauce contains gluten.
To motivate yourself, do your best to steer completely clear and then, perhaps on the weekend, you might try a portion of a bagel. (Bagels contain more gluten than other flour products). If you experience a clear reaction, it's time to get checked for celiac and get more advice from a doctor who takes this complaint seriously.
