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11 - Keeping Your Marbles

Death is not the greatest loss in life. The greatest loss is what dies inside us while we live.

—Norman Cousins

A healthy and vibrant body will serve you well as you age. But there is, of course, more to living well than physical health. Few things are more important than the healthy functioning of your mind. Remaining alert and clear-thinking is of great consequence throughout your life, and particularly as you move into your wisdom years.

Sadly, half of the people over age eighty-five in the United States suffer from dementia. Indeed, mental deterioration is so common among the elderly in the industrialized world today that many of us assume it is normal and inevitable as people age. In the cultures that exemplify healthy aging, in contrast, dementia is quite rare even among the oldest of the old. The authors of the Okinawa Centenarian Study report that Okinawan elders of both genders “have remarkable mental clarity even over the age of one hundred.” On the one hand, an ever-increasing number of older people in modern Western societies are suffering from Alzheimer’s disease and other forms of dementia, deteriorating inexorably to the point that they no longer remember who they are or recognize loved ones. On the other hand, the elders in Okinawa, Abkhasia, Vilcabamba, and Hunza are happily going about their lives in their nineties and beyond, fully present both mentally and emotionally, playing a needed and important role in their families and societies. The difference could hardly be more poignant.

ALZHEIMER’S DISEASE

Alzheimer’s disease, the most common form of dementia, is a degenerative disorder that progressively robs its victims of memory and judgment, eventually leaving them unable to carry out even the most basic functions on their own. Named after Alois Alzheimer, the German physician who first identified the disease in 1901, the disease initially wipes out short-term memory, then layer by layer destroys connections to the past. It generally takes eight to ten years to destroy its victims’ brains. At current rates, fifteen million elderly Americans will be stricken by 2050, and tens of millions of adult children will be drained by ever-mounting medical bills and endless hours of care.

The financial costs of Alzheimer’s disease are staggering. The disease already costs the U.S. Medicare system three times as much as any other disease, and the costs are increasing dramatically. Medicare spending on Alzheimer’s was $32 billion in 2000 and is expected to reach $50 billion by 2010, with an additional $30 billion from the U.S. Medicaid program. “If left unchecked, it is no exaggeration to say that Alzheimer’s disease will destroy the health care system and bankrupt Medicare and Medicaid,” says Sheldon Goldberg, president of the Alzheimer’s Association. The costs of caring for people with Alzheimer’s threatens to wipe out government health programs, and yet it is not the government but individuals and families who incur the vast majority of the costs. Many Americans think that Medicare covers nursing home expenses, but in fact Medicare was never intended to pay for long-term care, and generally pays only for hospital and physician expenses. And Medicaid will cover nursing home costs only after the patient’s assets have been reduced to $2,000 or less. Meanwhile, nursing home costs for an Alzheimer’s patient run $4,000 to $5,000 per month, and patients may need such care for many years.

A MIND IS A TERRIBLE THING TO LOSE

The writer and artist Bobbie Wilkinson tells of an experience she had while traveling:

I watched as she led him by the hand to the bathroom at the airport terminal. Travelers surrounded them, rushing past, and although he seemed a little bewildered, he seemed secure as long as his hand was in hers.

Returning to their seats at the gate, she combed his hair and zipped his jacket. He fidgeted and asked, “Where are we going, Mommy? What time is it? When will we get to ride our plane?”

I marveled at the woman’s patience and love. I watched her take him by the hand when they were finally allowed to board.

Upon finding my seat, I discovered that the three of us would be together. I squeezed past the two of them to my window seat, then told him how handsome he looked in his new coat. He smiled. She helped take off his jacket and buckle his seat belt. He said that he had to go to the bathroom again, and she assured him that he could last until the end of the flight. I hoped she was right.

As the jet engines started, he became frightened and searched for her hand. She explained what was going on and began talking to him about their trip. He was confused about the different relatives they would be seeing, but she patiently repeated herself until he seemed to understand.

He asked many more questions about the time, what day it was, how much longer until they got there—and she lovingly held his hand and gave him her full attention.

We introduced ourselves and shared the usual things all mothers like to share with one another. I learned she had four children and was on her way to visit one of them.

The hour passed quickly, and soon we were preparing to land. He became frightened again, and she stroked his arm, reassuringly. He said, “I love you, Mom,” and she smiled and hugged him. “I love you, too, Honey.”

They got off the plane before I did, the mother never realizing how deeply she had touched me. I said a quiet little prayer for this remarkable woman and for myself—that I would have enough love and strength to meet whatever challenges came my way, as this extraordinary mother clearly had.

When I last saw them, she was still holding his hand and leading her husband of 44 years to the baggage claim area.

I share this painful story not to be overly dramatic, but to illustrate something with which all too many of us are unfortunately familiar. There can be love and courage in the land of dementia, as Bobbie Wilkinson witnessed, but the sad reality is that Alzheimer’s exhausts the patience and endurance of even the most committed caregivers.

WHAT CAN BE DONE?

Unfortunately, Alzheimer’s disease is very difficult to treat. There are drugs (Cognex, Aricept, Exelon, Reminyl) that in some cases allow the patient to function for an extra few months. But these drugs are only palliatives that do nothing to slow the progressive neurodegen-eration that ultimately leads to dementia and death. In late 2003, the U.S. Food and Drug Administration approved a new drug, meman-tine (Namenda), for treating patients with moderate to severe Alzheimer’s. By blocking the action of the chemical glutamate, this new drug may help treat symptoms in some patients, but it does not modify the underlying pathology of the disease.

Our inability to cure or effectively treat Alzheimer’s makes prevention all the more important, and the examples of the world’s most healthy and long-lived societies all the more meaningful.

Is there anything that you can do to ensure that your mind as well as your body will remain healthy and vital? Are there practical steps you can take to help assure you of the ability to think clearly throughout the length of your days?

Absolutely.

The good news is that a tremendous amount has been learned about preventing Alzheimer’s and other forms of dementia. We now know a great deal about what you can do to maintain clear thinking well past the age of 100. And we have a good understanding of what it is about the lifestyles of the world’s most long-lived peoples that has consistently produced such marvelous cognitive functioning even at very advanced ages.

THE ROLE OF EXERCISE

For one thing, the regular physical exercise that is a central part of the lifestyles of these cultures is key. You may be surprised that physical exercise could play an essential role in preventing Alzheimer’s disease. But many studies have found that it can do exactly that.

For example, the value of exercise in sustaining healthy cognitive function was demonstrated in a five-year study published in Archives of Neurology in March 2001. The study found that people with the highest activity levels were only half as likely as inactive people to develop Alzheimer’s disease and were also substantially less likely to suffer any other form of dementia or mental impairment. Even those who engaged in light or moderate exercise had significant reductions in their risks for Alzheimer’s and other forms of mental decline. The study concluded that the more people exercise, the healthier their brains remain as they grow older. Three years later, in September 2004, The Journal of the American Medical Association published a series of studies further confirming that regular exercise helps preserve clear thinking even at advanced ages. One study found that women aged seventy and older who had higher levels of physical activity scored better on cognitive performance tests and showed less cognitive decline than women who were less active. Even walking only two hours a week at an easy pace made a marked difference, though the most benefits were found in women who walked six hours a week. Another study found that older men who walked two miles a day had only half the rate of dementia found among men who walked less than a quarter-mile a day. What are the mechanisms behind these benefits? In the last decade, neuroscientists have been discovering that exercise produces a multitude of positive changes in the brain. They are finding that physical activity enhances memory, improves learning, and boosts attention, as well as increasing abilities like multi-tasking and decision-making. A large number of studies have found that exercise makes the brain more adaptive, efficient, and capable of reorganizing neural pathways based on new experiences. Exercise, of course, increases the flow of oxygen to the brain. This in turn produces a larger number of capillaries in the brain, and possibly the production of new brain cells. It also boosts brain neuro-transmitters (including dopamine, serotonin, and norepinephrine) that play crucial roles in cognition.

PREVENTING ALZHEIMER’S BY EATING WELL

As well as exercise, there is diet. The Abkhasians, Vilcabambans, Hunzans, and elder Okinawans all eat whole-foods, plant-based diets high in antioxidants. This is now known to be one of the key reasons they have such extraordinarily low rates of Alzheimer’s and other forms of dementia.

Antioxidants are substances that keep you young and healthy by increasing immune function, decreasing the risk of infection and cancer, and, most important, by protecting against free-radical damage. Free radicals are cellular desperadoes that play a pivotal role in the aging process, and their damage takes a toll on virtually every organ and system in the aging human body. This in turn sets the stage for all sorts of degenerative diseases, including Alzheimer’s and other forms of dementia. Antioxidants neutralize free radicals and keep them in check.

Antioxidants are found in fresh vegetables, whole grains, fresh fruits, and legumes such as soy. Carotenoids, the substances that give fruits and vegetables their deep, rich colors, are antioxidants. Vitamin C and E are also antioxidants, as are the minerals magnesium and zinc. If your diet is high in antioxidants, your risk of many age-associated diseases—including cancer, heart disease, macular degeneration, and cataracts—decreases.

When it comes to preventing Alzheimer’s disease and other forms of senility and cognitive decline, antioxidants are extraordinarily important. It is free-radical damage that underlies the development of cognitive dysfunction, dementia, and most of the other ravages of unhealthy aging as well. And antioxidants are your body’s best defense against free-radical damage. Many scientists now believe that the reason people who eat plant-based diets have far less dementia is because plant foods contain far more antioxidants. Animal-based foods, on the other hand, typically tend to activate free-radical production and cell damage.

A large number of studies published in the world’s most prestigious medical journals have demonstrated the benefit of diets high in antioxidants in preventing Alzheimer’s and other forms of dementia and cognitive decline. What about supplements containing antioxi-dants? At present, the evidence is not as substantiated, but it is certainly encouraging. In January 2004, for example, a distinguished group of medical researchers from four U.S. universities published a study in the Archives of Neurology, finding that people taking both vitamin C and E supplements had a 78 percent lower rate of Alzheimer’s. Personally, I take supplementary antioxidants daily.

HEALTHY MIND, HEALTHY YOU

Throughout history, people have seen the elderly develop certain diseases and mistakenly believed those diseases were inevitable outcomes of aging. As recently as one hundred years ago, tuberculosis was the leading cause of death in the United States, and was thought to be a natural consequence of aging. Now we know, however, that tuberculosis is an infectious disease caused by a bacteria called My-cobacterium tuberculosis, and is spread through the air from one person to another.

Later, arteriosclerosis was considered a hallmark of aging. But then we learned that this condition is almost entirely avoidable with a healthy diet. Fifty years ago, most people believed that heart disease was simply part of nature’s script for human beings. But now we know many of the lifestyle factors that produce this illness. Even more recently, the decline in kidney function that had been attributed to the natural aging process has been found instead to be due to pathology.

Alzheimer’s is so common today in the industrialized world that many have come to view it as an inevitable adjunct of aging. Most people in nursing homes are there because of Alzheimer’s. But as widespread as it is, Alzheimer’s is a disease. It is not normal aging. It is not a natural condition. And it is not inevitable.

If you want to lower your risk for Alzheimer’s markedly, here’s the central thing you need to know: Study after study is finding that a whole-foods plant-based diet built on fresh vegetables, whole grains, and legumes—such as the diet eaten by the Abkhasians, Hunzans, Vilcabambans, and elder Okinawans—is good for brain function and dramatically lowers the incidence of Alzheimer’s and other forms of dementia.

Such diets also keep people from being overweight, keep cholesterol levels and blood pressure low, and reduce arteriosclerosis—all factors that are extremely important to retaining healthy mental functioning. In 2004, Dr. Miia Kivipelto of the Karolinska Institute in Sweden told an international conference on Alzheimer’s disease in Philadelphia of his 21-year study. The study found that people who were obese in middle age were twice as likely to develop dementia when they got old as those who were of normal weight. For those who also had high cholesterol and high blood pressure in middle age, the risk of dementia was six times higher. Many other studies also speak about the relationship between diet and the most serious forms of dementia, such as Alzheimer’s. They are saying that if you want to get Alzheimer’s disease, eat a diet high in meat, fat, saturated fat, cholesterol, sugar, and white flour. If you don’t, avoid such foods, and instead eat a diet high in fresh vegetables, whole grains, fresh fruit, and legumes, and be sure to get enough DHA and other omega-3 fats. In essence, if you want to prevent Alzheimer’s disease, eat as the Abkhasians, Vilcabambans, Hunzans, and elder Okinawans do.

THIS IS YOUR BRAIN ON MEAT

Another key to staying mentally clear as you grow older is keeping your homocysteine levels low. Homocysteine is a toxic amino acid, a breakdown product of protein metabolism, that has been strongly linked to Alzheimer’s and also to heart attacks, strokes, depression, and a type of blindness. Even small elevations in homocysteine can significantly increase the risk for these conditions. Notably, the elder Okinawans have among the lowest homocysteine levels in the world. Everyone has homocysteine in their blood, just as everyone has cholesterol. It’s a matter of how much. Problems occur when levels get too high. Blood levels of homocysteine are typically higher in people whose diets are high in meat and low in leafy vegetables, whole grains, legumes, and fruits—foods that provide folic acid and other B vitamins that help the body get rid of homocysteine.

How important is it to maintain low homocysteine levels if you want to prevent Alzheimer’s disease? On October 18, 1998, David Smith, M.D., and his colleagues from Oxford University presented their findings to the American Medical Association’s annual Science Reporters’ Conference. Their study, published in Archives of Neurology the following month, found that the risk of getting Alzheimer’s disease was a monumental 4.5 times greater when blood homocys-teine levels were in the highest one-third. Folic acid and vitamin B12 are key factors in preventing Alzheimer’s, because blood levels of homocysteine can be reduced by increasing your intake of folic acid (also called folate) and vitamin B12. One study found that the incidence of Alzheimer’s was a staggering 3.3 times greater among people whose blood folic acid levels were in the lowest one-third range, and 4.3 times greater for those with the lowest levels of B12. In 2001, the journal Neurology published the results of a three-year Swedish study of 370 healthy elderly adults. The study found that those with even slightly low levels of vitamin B12 and folic acid had twice the risk of developing Alzheimer’s disease compared to those with normal levels. What is the best way to achieve the ideal scenario of a high blood folic acid level and a low blood homocysteine level? A whole-foods, plant-based diet with plenty of green leafy vegetables and ample vitamin B12. (For people who eat this way and yet still have high homo-cysteine, daily supplementation with 800 mcg folic acid, 500 mcg vitamin B12, and 50 mg vitamin B6 can be helpful. The methylcobal-imin form of B12 is far more effective than the cyanocobalimin form.) It is particularly important for vegetarians and vegans to understand that adequate levels of vitamin B12 are necessary for folic acid to effectively carry out its functions. Vegans who do not eats foods fortified with B12 or take B12 supplements to ensure they get adequate vitamin B12 are at significant risk for elevated homocysteine levels. But this is no reason to eat meat. In fact, it is meat-eaters who are most commonly at risk for high homocysteine levels, because animal foods (and meat in particular) tend to contribute to the production of homocysteine. One study found that subjects who ate meat as their main source of protein were nearly three times as likely to develop dementia as their vegetarian counterparts. A survey of the medical literature on diet and Alzheimer’s noted how frequently a meat-centered diet raises homocysteine levels. The report was aptly titled “Losing Your Mind for the Sake of a Burger.”

EAT WELL, THINK CLEARLY

In the West today, we often take for granted that aging will bring restricted short-term memory and diminished mental faculties. A visit to most nursing homes demonstrates how commonly and how markedly people in our society experience cognitive decline as they age. As one comedian described it, “First you forget names, then you forget faces, then you forget to pull your zipper up, then you forget to pull your zipper down.” But there is good science to show that many of us can experience clear thinking well into our later years. The examples of the world’s healthiest and longest lived cultures and the findings of medical science are in agreement. They are both saying that there are definite steps you can take to greatly reduce your risk of Alzheimer’s and many other diseases. If you want to create an elderhood of health and clear thinking: Eat a healthful plant-based diet with lots of fresh vegetables, whole grains, legumes, fruits, seeds, and nuts. This is a diet that provides plenty of antioxidants and fiber and produces clean arteries enabling a rich blood supply to the brain.

Avoid foods that are high in fat, saturated fat, and cholesterol.

Keep your homocysteine levels low by making sure you consume plenty of vitamin B12, folic acid, and vitamin B6, and by keeping your meat intake to a minimum.

Make sure you consume plenty of DHA, the long-chain omega-3 fatty acid.

Get lots of regular physical exercise.

The exciting news is that if you follow the example of the longest-lived and healthiest people in the world, you nurture the possibility of a very different kind of future than is the norm in the industrialized world. You can take decisive steps toward a long, vibrant life, rich in physical strength and mental clarity. Even if you have eaten poorly and not exercised for most of your life, shifting now in a healthy direction greatly improves your prospects for the remainder of your life.

GOOD SCIENCE ON HOW TO PREVENT ALZHEIMER’S

Multiple studies published in Archives of Neurology, the American Journal of Epidemiology, and other medical journals have found that people who eat diets high in fat, saturated fat, and cholesterol have at least double the risk of developing Alzheimer’s disease. In 2006, a study published in Annals of Internal Medicine found that older adults who exercise three or more times a week have a 30 to 40 percent lower risk of developing dementia than their more sedentary counterparts.

Studies published in the Journal of Alzheimer’s Disease and The Journal of the American Medical Association compared Alzheimer’s rates to dietary variables in eleven different countries and found the highest rates of the disease among people with a high fat intake and low intake of whole grains.19 A study of three thousand Chicago residents aged sixty-five and older published in the Journal of Neurology, Neurosurgery, and Psychiatry in 2004 found that those with the lowest intake of dietary niacin (vitamin B3) were 70 percent more likely to develop Alzheimer’s than those with a higher intake, and their rate of cognitive decline was twice as fast. (Good dietary sources of niacin include whole grain wheat products and green leafy vegetables). A large study published in Archives of Neurology in 2003 found that older people can reduce their risk of developing Alzheimer’s disease by eating fish, consuming fish oil, or taking DHA supplements. Participants in the study who consumed fish once a week had a 60 percent lower risk of developing the disease than did those who rarely or never ate fish. Participants whose daily intake of DHA was above 100 mg/day had an incidence of Alzheimer’s which was 70 percent lower than those with an intake of 30 mg/day or less.