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Ask anyone over age 40 what they most fear in old age, and chances are that memory loss—and its far more serious cousins, dementia and Alzheimer’s —are at the top of the list, right up there with running out of money.
We’ve all had some contact with dementia or Alzheimer’s. Whether a friend, relative, mother, father, or spouse, no one is ever more than six degrees of separation from this degenerative disease, which not only robs us of our sense of self, but has the potential to bankrupt the entire U.S. health care system. In 2014, the cost of treating Alzheimer’s was $214 billion, most of which went to nursing homes and home care. By 2050, the cost is expected to exceed $1.5 trillion.
For many people, the thought of developing Alzheimer’s is almost worse than death. As my own mother put it, when talking about my father’s final years with dementia, “It’s like he’s there … but he’s not.” The last years of an Alzheimer’s patient are indeed a dismal affair, aptly characterized by Nancy Reagan as “the long goodbye.”
Emerging Research on Alzheimer’s Disease
The good news is that a growing band of scientists are beginning to conclude that we have more control over brain health than was previously believed. Some—like Board Certified Family Physician Steven Masley, MD, author of The Better Brain Solution—believe there’s reason to hope that we may be able to win the war against memory loss, brain degeneration, and even Alzheimer’s itself. Others—like Dale E. Bredesen, MD, professor and founder of the Buck Institute and author of the new book, The End of Alzheimer’s—agree.
I asked Masley—who is best known for his book, The 30 Day Heart Tune-Up and his PBS Special, 30 Days to a Younger Heart—why an expert on heart disease would turn his attention to the brain. “It turns out there’s a direct connection between the health of the heart and the health of the brain,” he told me. “The risk factors for heart disease, diabetes, and Alzheimer’s overlap considerably.”
Older people with hypertension (long considered a major risk factor for heart disease), for instance, have a 300 percent increased risk for Alzheimer’s. So do diabetics, and that’s just for the ones not using insulin. Diabetics who use insulin see their risk for Alzheimer’s go up a whopping 400 percent, just a bit more than the increased risk that comes with having a certain form of the so-called Alzheimer’s gene, ApoE4.
Alzheimer’s and High Blood Sugar
Why would diabetes be a risk factor for a disease of the brain? According to Masley, “uncontrolled blood sugar is one of the most significant origins of memory loss.” Integrative neurologist and author of Grain Brain, David Perlmutter, MD, agrees. “The relationship between poor blood sugar control and Alzheimer’s disease is so strong that researchers are now calling Alzheimer’s ‘Type 3 Diabetes,’” he says.
To understand why, you have to know a little about something called insulin resistance, which is at the core of type 2 diabetes. As it turns out, it’s centrally involved in Alzheimer’s as well. And that’s where things get interesting—because it all starts with the food you eat.
When you eat, food gets broken down (digested) into components such as fatty acids, amino acids, and sugar (glucose), which then travel out of the gut and into the bloodstream. This causes your blood sugar to rise—even more so when you eat a high-carb meal that breaks down into a lot of sugar. When blood sugar rises, the pancreas releases insulin, which helps transport that sugar from the blood into the muscles, where it can be used for energy.
When blood sugar is continually raised—as it is with a typical, high-carb American diet—the pancreas has to secrete more and more insulin to get the job done. And if you’re also not exercising, your muscles don’t need that much sugar to begin with, so they begin to refuse entrance to insulin and its sugar payload. Insulin then takes the sugar to be stored in fat cells, which continue to accept it for a while, as you’ll be able to observe all too easily. But eventually, even the fat cells stop sucking up sugar, the state known as insulin resistance—cells resist the action of insulin and leave it (and the sugar it carries) stranded in the bloodstream.
High blood sugar and high insulin levels are really bad for your heart, and as it turns out, your brain, as well. “Insulin resistance can make you up to 60 percent more likely to develop Alzheimer’s,” says Masley. “The brain desperately needs insulin to deliver glucose to brain cells. When you’re insulin resistant, your brain cells can’t get the fuel they need and they begin to die. That’s when you’re on the road to dementia or Alzheimer’s.”
And that’s why a growing number of scientists are calling Alzheimer’s disease, “type 3 diabetes.”
One of the hallmarks of the Alzheimer’s brain is an accumulation of something called beta-amyloid plaque. Controversy continues to reign about whether the plaques are a cause or a result of Alzheimer’s, but they’re always present in cases of the disease. “The enzyme needed to break down insulin is the very same enzyme needed to break down beta-amyloid plaque,” Masley says. “When there’s excess insulin in the brain, the enzyme gets diverted by the insulin and doesn’t break down beta-amyloid plaque effectively.”
Reducing Inflammation Related to Diabetes and Alzheimer’s Using Diet
Luckily, type 2 diabetes is a disease that is enormously responsive to dietary and lifestyle changes. If Alzheimer’s disease turns out to be a result of the same mechanism that causes diabetes, then the same changes that reduce the risk for (or in some cases reverse) diabetes should be able to reduce the risk for Alzheimer’s.
One factor common to diabetes and Alzheimer’s is inflammation, which causes, accompanies, promotes, or exacerbates every known degenerative disease. Not surprisingly, then, inflammation is considered to be a main target in the battle for brain health.
Perlmutter’s Grain Brain Life Plan program states that one of the first goals is to reduce and control inflammation. According to Perlmutter, one of the best ways to keep inflammation in check is to maintain healthy blood sugar levels.
In Masley’s book, The Better Brain Solution, he outlines a multifaceted program designed to control blood sugar and reduce inflammation. Note the emphasis on multifaceted—it’s not an accident.
Multipronged approaches to brain health and Alzheimer’s protection work better than any “single” intervention. Dale Bredesen’s book, The End of Alzheimer’s, outlines a comprehensive program that includes lifestyle-focused interventions. Like Masley, Bredesen recommends nutritional supplements, brain-nourishing foods, blood sugar control, hormone training, proper sleep, and brain training. In one study of 10 patients with symptoms of memory loss, nine displayed improvement in cognition within 3–6 months on this program, and many who had stopped working were able to return to work.
The Comprehensive Plan for Brain Health
The Better Brain Solution applies the knowledge gained from putting thousands of patients at the Masley Optimal Health Center in Florida through the program and carefully monitoring results. The book outlines four key pillars for maintaining a healthy brain: food, nutrients, exercise, and—not surprisingly, as stress is a huge source of inflammation—stress management.
For his part, Masley recommends a modified Mediterranean-style diet that’s rich in food sources of good fats, such as nuts, seeds, avocados, and olive oil; additional sources of supplemental healthy fats, including fish and MCT oils; and “clean,” nontoxic sources of protein, such as grass-fed meat and wild salmon.
With a few minor differences, this is the program that all of today’s “brain pioneers” are advocating. None of the authors mentioned in this article recommend low-fat diets, and none are particularly concerned about saturated fat. “Saturated fat may not help you, but it certainly isn’t going to hurt you,” says Masley.
In fact, because fat is the one macronutrient that does not raise blood sugar or insulin levels, it plays a particularly important role in the diets of those who want to manage their blood sugar and insulin while keeping their brains healthy and sharp.
In addition to diet, virtually all of the optimistic pioneers in this integrative and functional way of thinking about brain health—the three doctors cited above as well as others such as Daniel G. Amen, MD—agree that no brain health program is complete unless it incorporates relationships, feelings and connections to others.
“Loneliness,” says Masley, “is linked to depression. Relationships matter in every area of health, including—or especially—in brain health. We all have to remember that we can’t go it alone.”
Brain Health Reading List
- The Better Brain Solution, Steven Masley, MD
- Change Your Brain, Change Your Life, Daniel G. Amen, MD
- The Grain Brain Whole Life Plan, David Perlmutter, MD
- The End of Alzheimer’s, Dale E. Bredesen, MD
- Brain Maker, David Perlmutter, MD
- The Brain Trust Program, Larry McCleary, MD
- The Brain Warrior’s Way, Daniel G. Amen, MD, and Tana Amen, BSN, RN