6 Foods You Should Avoid, According To Brain Docs


You hear plenty about brain-boosting foods like berries and salmon that can save your memory and keep your brain sharp. And yes, you’re smart for eating them. But what about the cognitive culprits that wreak havoc on your noggin, leading to brain fog, or worse, Alzheimer’s? We hit up top brain docs, from neuroscientists to psychologists, for the cranium killers they avoid—because it turns out what you don’t eat is just as important as what you do. Here’s what’s on their “don’t” list.

Artificial Sweeteners


“Everyone talks about gluten and carbs and sugar, but we should be paying attention to artificial sweeteners, too. Last year, a group of Israeli researchers demonstrated that when you consume non-caloric sweeteners, it changes your gut bacteria in a way that sort of paves the way for type 2 diabetes. And if you become diabetic, you have 4 times the risk of being diagnosed with Alzheimer’s disease. The reason: Diabetes makes you less sensitive to insulin, so your bloodsugar rises, which dramatically increases your risk of brain degeneration. Surprisingly, people consuming artificial sweeteners have an even higher risk of developing diabetes than people who drink sugar-sweetened beverages—not that I’m advocating those instead.”
— David Perlmutter, MD, neurologist and author of Grain Brain and The Grain Brain Whole Life Plan, out in November

High-Mercury Fish


“I don’t like to single out one food as bad—everything in moderation, I like to say—but the one caveat is mercury, which is mostly found in fish, particularly big ones that live longer and thereby accumulate more of this neurotoxin. Mercury affects people cognitively, in terms of thinking, but it particularly affects the cerebellum, the part of the brain that controls balance, coordination, and vision. I’m definitely mindful of my mercury intake; and while I do eat tuna, I make a point of having it no more than once a week, or having it in smaller dishes like sushi rolls.”
Gail Saltz, MD, clinical associate professor of psychiatry at New York-Presbyterian Hospital/Weill Cornell School of Medicine

Want to reduce your exposure to mercury found in fish? Follow this advice from the Environmental Protection Agency:
1. Do not eat shark, swordfish, king mackerel, or tilefish, as they contain high levels of mercury. (Here are 12 fish you should definitely stay away from.)
2. Eat up to 12 oz (2 average meals) a week of a variety of fish and shellfish that are lower in mercury such as shrimp, canned light tuna, salmon, pollock, and catfish.
3. Limit consumption of white (albacore) tuna to 6 oz a week.

MORE: Is It Safe To Eat Tuna Everyday?

Prepared Biscuits


“I avoid prepared or packaged ‘flaky’ biscuits and ‘flaky’ pizza crust. Often, trans fat is used to produce this texture, so this term is a red flag for the danger inside! (Avoid margarine and movie theater microwave popcorn as well.) Although most trans fat has been banned or removed, it can still be snuck in—as long as there’s less than 0.5 g of trans fat per serving, companies can still say their product is trans fat–free. Trans fat wreaks havoc on the brain leading to brain shrinkage, inflammation, and interrupted nerve transmission. Studies show that trans fat can even damage your memory.”
Dr. Susan Albers, PsyD, clinical psychologist at Cleveland Clinic and New York Times best-selling author

Sugary Drinks


“I avoid sugary drinks because the brain’s weight-regulation system doesn’t seem to compensate correctly for their calories. Neurons in the hypothalamus normally match calorie intake to energy burned via exercise at an accuracy of over 99%, but the evidence suggests that sugary drinks don’t reduce hunger as much as solid foods with the same number of calories—prompting us to eat more than we need to. Since I rely on hunger and fullness signals to guide my eating, I need that system to work correctly. To help it, I eat whole foods, get regular exercise, and avoid empty calories from foods like soda.”
Sandra Aamodt, PhD, neuroscientist and author of Why Diets Make Us Fat



“After a thorough review of the available medical literature, including cases of psychosis and depression being reversed on a gluten-free diet, I began to implement this recommendation in my practice, only to find patient after patient with improvements from clearer thinking to flatter stomachs to hairregrowth. Gluten in modern foods is a ‘Franken-grain,’ hybridized and chock-full of immune-stimulatory protein—and that’s before it’s sprayed with toxic herbicide and processed into products with genetically modified ingredients andsugar. For many, it’s gut-brain sabotage, and whether it is for you can only truly be determined through complete elimination of everything containing flour, from bagels to bread to pasta to soups to packaged foods with hidden sources of gluten. This is another reason why sticking to whole, organic foods such as meats, eggs, vegetables, fruit, nuts and seeds, and oils, is the quickest means of eliminating health problems.”
Kelly Brogan, MD, a Manhattan-based holistic women’s health psychiatrist and author of A Mind of Your Own

MORE:Should You Go Gluten-Free?

Processed Foods


“In my opinion, it’s best to avoid processed foods, including fast food and soda. These foods often contain trans fats, which are harmful for the brain and heart, along with high amounts of sugar and other artificial ingredients. When consumed on a regular basis, these ‘faux foods’ displace real foods that provide beneficial nutrients for the brain and overall health and wellness. These foods may also promote obesity and inflammation, which are harmful for the brain.”
Dianna Purvis Jaffin, PhD, director of strategy and programs at the Center for BrainHealth’s Brain Performance Institute at the University of Texas at Dallas