You can buy brains from the butcher to cook and eat, but this is not what Mosconi means when she refers to brain food.
Lisa Mosconi has a web and media presence and a book Brain Food: The Surprising Science of Eating for Cognitive Power. She claims, “There is increasing evidence that implementing the lifestyle changes described in this book has the potential to prevent Alzheimer’s from developing and also to help slow down or even halt progression of the disease.” What’s more, “eating for your brain…actually helps you achieve peak performance in every part of your life.”She says, “The human brain has its own unique diet, different from the rest of the body.” The evidence presented in her book does not support that claim. In fact, the diet she recommends for brain health is also a diet for bodily health.
Others have speculated…
In my SkepDoc column in Skeptic magazine (text available online) I reviewed the video series “Awakening from Alzheimer’s,” in which a journalist interviews numerous “experts” and claims that Alzheimer’s is for the most part preventable and can be reversed in 9 out of 10 patients! The recommendations of those “experts” are all over the map. There is nothing even remotely approaching a scientific consensus. They claim the main cause of Alzheimer’s is everything from gluten to obesity to lack of sleep to chronic Lyme disease to toxins spewed by “leaky gut” syndrome. They claim to have reversed Alzheimer’s with a wide variety of treatments: everything from coconut oil to a ketogenic diet to probiotics to strenuous exercise to various long lists of dietary supplements to psychological interventions that are considered successful if they make patients cry. There is no satisfactory evidence to support any of their claims.
What science says
There are several known modifiable risk factors for Alzheimer’s, according to a Lancet review:
- low levels of education
- midlife hearing loss
- physical inactivity
- high blood pressure (hypertension)
- type 2 diabetes
- obesity
- smoking
- depression
- social isolation
Notice that poor diet is not on the list. They recommend active treatment of hypertension, more childhood education, exercise, maintaining social engagement, reducing smoking, and management of hearing loss, depression, diabetes, and obesity. They do not recommend specific dietary interventions or supplements. They estimate that lifestyle interventions “might have the potential to delay or prevent a third of dementia cases.”
But about 65% of the risk is still due to factors you can’t control, such as ageing and family history.
there’s strong evidence that several factors associated with leading a healthy lifestyle may play a role in reducing your risk of Alzheimer’s disease and other types of dementia. However, more research is needed before any of these factors can be considered a proven strategy to prevent Alzheimer’s disease.
Mosconi is not waiting for more research.
Mosconi says, “The human brain has evolved over millions of years to absorb specific nutrients and to function on a relatively specific diet.” I don’t think that’s true; I think we have evolved to thrive on a wide variety of diets. Our ancestors ate whatever food they could get.
She repeats many of the standard memes of alternative medicine: doctors only treat symptoms, nutrition is not taught in medical schools, our soil is depleted, our food is less nutritious…pesticides, toxins, etc.
She says the brain is the one most easily damaged by a poor diet. Maybe, but she provides no evidence that the brain is damaged when people follow the nutritious, well-balanced, varied diet that is recommended by most mainstream scientists and doctors.
She shows two MRI images to contrast the effects of the Mediterranean diet and the Western diet on brain anatomy. As if two individual scans could prove anything.
Water
She repeats the oft-refuted advice to drink at least 8 glasses of water a day. She claims that drinking water improves cognitive performance. Her citation for that claim is a small study in which participants were instructed to fast overnight and not eat or drink anything after 9 pm, so they were presumably somewhat dehydrated. There is no evidence that people who are not dehydrated benefit from increasing water intake.
She says purified water is bad because essential minerals are missing. She makes the ludicrous claim that purified water is “entirely incapable of hydrating you”! As sources of water she recommends coconut water and aloe vera juice, but she doesn’t provide any evidence that they have significantly beneficial effects compared to plain old tap water. She says energy drinks are not good for you because they are “chockful of manufactured minerals and salts.” Again, no references.
She concludes:
…simply drinking more water and eating water-rich foods could be one of the healthiest changes you make to bring about better health as well as greater cognitive power in your life.
I suppose it “could” be, but I seriously doubt it.
She covers all the major nutrient groups, and her thinking falls into this simplistic sillygism:
- The brain uses nutrient X
- Foods A, B, and C are high in nutrient X
- Therefore you need to eat those foods to be healthy.
This is the same fallacious argument made for superfoods. The same levels of dietary nutrients can be supplied by eating more of other foods. Caviar contains more omega-3s than salmon, but the typical serving of caviar is much smaller than the typical serving of salmon. And it’s possible to get plenty of omega-3s in a varied diet without eating either one.
Standard advice coupled with questionable ideas
Much of what she says is standard health advice. Avoid trans fats. Eat fresh vegetables and fruit. Avoid processed foods. Limit red meat consumption. It’s better to get your nutrients from food than from supplement pills. Exercise, get adequate sleep, and avoid stress. Since the brain runs on glucose, she wouldn’t agree with the low-carb diet folks; she says we need adequate sources of glucose in our diet, and recommends complex carbs, paying attention to the glycemic index.
She provides many examples of observational studies where lower intakes of a certain nutrient were correlated with cognitive impairment. Obviously, if someone is deficient in a vitamin or other nutrient, the deficiency should be corrected. But she doesn’t have any evidence from prospective interventional studies showing that, in practice, altering diet significantly improves cognition for people who are deficient, much less in people who are not deficient.
Often her language is not that of a scientist. She uses buzzwords like detoxification and boosting the immune system. She avoids GMOs and things that she thinks are unnatural like “manufactured” minerals and salts. She says she takes royal jelly daily for its natural antibiotic effects; she says these effects are “known, but perhaps not scientifically confirmed.” If not scientifically confirmed, how are the effects “known”? She says plants produce phytonutrients to increase their life span, and then she leaps to the conclusion that humans will derive the same benefits from eating the plants.
She says by committing to drinking 8 glasses of water a day, you can increase your focus and reaction time by as much as 30%. There is no evidence to support that claim.
At the end of the book, she provides an 80-question test you can take to see how well you’re following a brain-healthy diet. The test has not been validated, so it’s hard to say what a high or low score really means. Then she provides meal plans and recipes.
The ingredients in her recipes are representative of her thinking. Local raw honey. Organic everything. Free-range eggs. Organic, grass-fed whole milk (I assume she means feeding grass to the cows, not feeding it to the milk). Filtered water. Goji berries. Açai berry powder. Ginseng extract with royal jelly and bee pollen. Organic spirulina powder. Even Himalayan pink sea salt, for heaven’s sake! Good grief!!
Where did she go wrong?
Mosconi holds a dual PhD in neuroscience and nuclear medicine. She is the associate director of the Alzheimer’s Prevention Clinic at Weill Cornell Medical College/New York-Presbyterian Hospital, and the founder of the Nutrition and Brain Fitness Lab at New York University School of Medicine. With her training and experience, she ought to understand and practice rigorous science. She makes all the right noises about scientific literacy and recognizing pseudoscience, but she seems unable to look in the mirror and see her own errors.
She reveals where she went astray. In a lecture she gave, she lamented the failure of science to offer a cure for Alzheimer’s or even an effective treatment. Someone in the audience asked, “How about olive oil?” She realized she didn’t know anything about the effects of nutrition on Alzheimer’s. She seems to have assumed that diet must be crucially important, and for some reason instead of studying conventional nutrition science, she got a degree in Holistic Nutrition. She bills herself as a certified Integrative Nutritionist and holistic healthcare practitioner. I couldn’t find where she studied, but Stephen Barrett has criticized the Institute for Integrative Nutrition on Quackwatch. Its training is not based on scientific nutrition. It seems most programs in Integrative Nutrition are 6- to 8-month correspondence courses with no prerequisites. I wonder what she was taught.
Conclusion: Healthy diet yes, brain diet maybe (who knows?)
Mosconi does not make a persuasive argument that the brain requires anything unique, anything more than the same good nutrition that benefits the entire body. Her Brain Food plan provides much good advice about healthy lifestyle and diet, but the good advice is mixed with unsupported claims, speculations, extrapolations that go far beyond the evidence, and some very questionable ideas. (Himalayan pink sea salt? Water that doesn’t hydrate?) Her plan might reduce the risk of Alzheimer’s; it might not. Is it any better than any of the many other plans recommended in the “Awakening from Alzheimer’s” videos? The only way to tell would be to do controlled studies, which have not been done or even contemplated, as far as I could see. It might not be any better than the general health advice provided by science-based conventional medical practitioners. There may be no difference between eating for your brain and eating for your entire organism.
This article was originally published in the Science-Based Medicine Blog.