Mind your body, because your brain is at stake.
We have long known that the more common, dire, and dreaded threats to our minds—Alzheimer's disease in particular—have a great deal to do with overall health status below the neck. Study after study after study after study that has shown an elimination of up to 80 percent of all chronic disease with the application of lifestyle as medicine has NOT carved out an exception for Alzheimer's, or dementia in general.
The evidence that we can alter gene expression with the power of lifestyle almost certainly pertains to Alzheimer's as it does to cancer. By minding our bodies, we can mind our minds, too. We can best mind both by minding the short list of what matters most to health: eating well, being active, managing our weight by virtue of these first two, and avoiding tobacco.
Available evidence suggests that controlling cardiac risk factors can lower dementia risk specifically by 50 percent or more. But as understanding of the likely root causes of Alzheimer's advances, the prospects for prevention are, if anything, improving.
A consensus has been emerging over recent years that Alzheimer's may reasonably be characterized as "type 3 diabetes," or diabetes of the brain. Under experimental conditions, insulin resistance and diabetes have been shown to cause virtually all of the changes in brain structure and function seen with Alzheimer's.
What makes this good news is that type 2 diabetes is eminently preventable.
The Diabetes Prevention Program, a fairly moderate program of dietary improvement and habitual exercise, resulting in an average weight loss of 7 percent, prevented diabetes in nearly two-thirds of high-risk adults.
With application of lifestyle as medicine before such a high-risk state develops, most experts consider type 2 diabetes as much as 95 percent preventable, and I share this view. To the best of our collective current knowledge, the same pertains to type 3 diabetes.
Insulin resistance, and other antecedents of diabetes such as the metabolic syndrome, are often propagated by an excess of fat around the middle. So one of our new-age mantras ought to be: lose the belly, keep the brain! Easier said than done, I know, but possible, particularly if we make it a societal as well as personal priority.
[See Is Obesity Cultural?]
Insulin resistance generally improves with routine exercise, and/or weight loss. A variety of healthful diets, from vegan to Mediterranean, have been shown to confer benefits as well. Specific dietary factors known to be beneficial include soluble fiber found in whole grains, beans, lentils, berries, and apples as well as healthful, unsaturated oils including monounsaturates and omega-3s found in walnuts and other nuts, flaxseeds, olives, avocados, fish, and seafood.
[See Recipe for Health]
The latest bit of actionable information for defense against dementia is courtesy of a long-running observational study out of the Cooper Clinic in Dallas, Tex. Adults with the highest levels of fitness in midlife have the lowest levels of dementia in late life. The study does not prove cause and effect, but in context, that does seem very likely. The highest level of fitness at age 50, other things being equal, was associated with more than a 35 percent reduction in the likelihood of dementia after age 65.
It is only fair and honest to concede that we do not have perfect defenses against Alzheimer's. And, to some extent, we are hoisted on our own petard—vulnerable to this condition of advancing age because we are better at living longer than ever before. As grim as some of what tends to happen to us in our 80s or 90s may be, it is a byproduct of living into our 80s or 90s, which people didn't used to do nearly so often. Even so, we all share the hope of going gentle—and with our marbles—into that good night.
While an inventory of potential brain foods can be assembled, the evidence is much stronger for the importance of the overall dietary pattern. Eating well is as important to the brain as it is to the heart. Lower your risk of Alzheimer's with plenty of vegetables and fruits, whole grains, beans and lentils, olives and avocado, nuts and seeds. Limit consumption of highly-processed foods, fast foods, sugar, salt, saturated and trans fat.
Population studies consistently suggest that those who exercise their brains protect their minds from dementia. Crossword puzzles and Sudoku are aerobics for your brain. Just as physical activity defends the body against aging and infirmity, mental activity seems to help preserve the vitality of the brain.
As we mind our mind by minding our bodies, we can mind our business into the bargain. The price tag of Alzheimer's—and chronic disease in general—threatens nothing less than our national solvency. Only prevention can solve that problem. A breakthrough drug for Alzheimer's would be wonderful, but who is naïve enough to think the drug would be dispensed for free? Serious chronic disease is bad financial news when we can't treat it, and still bad financial news when we can! The financial news turns to the good only with prevention.
Lifestyle is not only the best medicine we have—it is the only medicine we have already available to all, at essentially no extra cost, and without a prescription.
So eat well, and avoid tobacco. By all means, exercise your brain. It can't hurt, and if the exercises are directed to practical objectives, only good can come of it. But be sure to listen to Beyoncé, and move your body! Move, and mind your body for many good reasons, but now add this to that list: A healthy body is the best-established resource we have to mind, and preserve, the robust workings of our minds.
[See Top-Rated Diets Overall]
Hungry for more? Write to firstname.lastname@example.org with your questions, concerns, and feedback.
David L. Katz, MD, MPH, FACPM, FACP, is a specialist in internal medicine and preventive medicine, with particular expertise in nutrition, weight management, and chronic-disease prevention. He is the founding director of Yale University's Prevention Research Center, and principal inventor of the NuVal nutrition guidance system. Katz was named editor-in-chief of Childhood Obesity in 2011, and is president-elect of the American College of Lifestyle Medicine.