Preventing the Development of Alzheimer's

Written by Allan Reder

Scientists are looking at what can preserve your mental capacities and hold off alzheimer's disease and dementia?

National Public Radio's Daniel Schorr is the kind of guy who would make any aging news junkie stand up and cheer. On July 19, 2006, Schorr turned 90, yet he still performs at an undiminished level in one of the most demanding jobs in today's media. He began his career at CBS News in 1953 and joined NPR as its senior news analyst at 69, an age at which many of his colleagues had long been put out to pasture. In his position, he has to pack his cerebral hard drive with massive amounts of information, and then he has to possess the Pentium-esque agility to mine that information for insights worthy of NPR's highly educated listeners. Schorr pulls off the challenge with effortless grace.

But Schorr's beat-the-clock competence calls attention to an issue with implications for everything from lifestyle choices to national social policy. Because of advances in medical science, people are living much longer than ever before. The US Census Bureau projects that the number of elderly aged 85 and older will more than triple from about 4 million today to about 14 million by 2040. That includes many of us reading this article.

Unfortunately, we won't all age like Daniel Schorr. Some of us will live out our dotage without all our marbles. Alzheimer's disease or other forms of dementia will rob us of our intellectual abilities, our short-term memories, our personalities, and even the ability to recognize the people we love the most. The prospect is terrifying—especially because researchers don't yet understand exactly what causes Alzheimer's (or dementia) or how to prevent it or even slow the destruction.

But they are making progress on those fronts. Lots of indicators point toward a health regimen that may preserve your mental capacities well into old age, and perhaps indefinitely. The even better news? If you're already practicing a healthy lifestyle as that concept is currently understood, you may be most of the way home.

A New Understanding

No one fully knows what causes Alzheimer's but the research community is beginning to feel it's at least driving in the right neighborhood. Current thinking suggests that the disease results from a complex dance between several partners: lifestyle factors such as food choices, environmental factors such as educational level and previous head injuries, and a person's inherited genes. Recently, scientists have focused on the strong link between cardiovascular disease and Alzheimer's. Mounting evidence suggests that cardiovascular risk factors such as high cholesterol, high blood pressure, and poor dietary habits also significantly boost the risk for Alzheimer's in particular and cognitive decline in general.

For instance, a Finnish study involving nearly 1,500 subjects found that high cholesterol and blood pressure were even more tightly tied to Alzheimer's than the so-called APOE-4 gene, the genetic risk factor associated with the most common form of the illness. Other studies corroborate this connection by showing that controlling cholesterol and blood pressure levels helps keep the brain healthy.

In a similar vein (so to speak), researchers are also exploring a connection between diabetes and Alzheimer's. They've known for a while that having diabetes nearly doubles an individual's chance of developing Alzheimer's.

Diabetes, itself a cardiovascular risk factor, can create vascular problems, and vascular disease increases the risk of Alzheimer's. Some scientists have also proposed that Alzheimer's may be a third form of diabetes (besides Type 1 and Type 2) that directly leads to brain cell death and other abnormalities associated with Alzheimer's. And poorly controlled diabetes—with wildly fluctuating blood sugar levels—is also thought to heighten the risk of getting Alzheimer's.

The most current study in this area points to increased Alzheimer's risk for people with high blood sugar or "pre-diabetes." Elevated blood sugar sends an early signal that Type 2 diabetes lurks on the horizon. The social implications for the US look ominous given the fact that many more people currently suffer from pre-diabetes than Type 2 diabetes, which currently runs rampant in this country, the end result of the obesity epidemic. The diabetes findings, from a Swedish study, were presented at the Tenth International Conference on Alzheimer's Disease and Related Disorders, a major conference held in Madrid in July 2006. The essential message to the public is clear: If you protect yourself against diabetes by controlling your weight, exercising, and eating a healthy diet (see below), you may as a bonus preserve your gray matter, as well.

One last uncomfortable thought: Scientists now recognize that Alzheimer's can be present in the brain without seeming to affect a person's thinking or behavior. "You could be completely normal and have that pathology," says leading Alzheimer's researcher David Bennett, MD, director of Rush University's Alzheimer's Disease Center, "so I think that the biggest thing that is changing is the recognition that the disease is a much larger problem than has historically been recognized."

Keeping Dementia at Bay

As researchers' understanding of Alzheimer's and other forms of cognitive decline grows, so does their confidence in a group of lifestyle options that may ratchet down the risk for these diseases. Students of healthy living will find the laundry list that follows pretty darn familiar, at least those items related to diet and exercise. When it comes to these two lifestyle categories, one size seems to fit nearly all.

For instance, a previous article in this magazine (Fall 2006) suggested that a heart-healthy diet not only offers protection against cardiovascular disease but also colon cancer, diabetes, and prostate cancer. Add Alzheimer's to the pile. Here are the details, plus the rest of the easy steps that can, as the Alzheimer's Association puts it, "maintain your brain." Healthy Eating Low fat. Low cholesterol. Dark-skinned veggies and fruit. Cold-water fish such as halibut, mackerel, salmon, trout, and tuna. Nuts such as almonds, pecans, and walnuts. If you've studied healthy eating and applied what you've learned, you're already eating this way. And recent research suggests that your brain will thank you.