Authors: John Robbins
HEALTHY AT 100 (29 page)
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.
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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.
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.
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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.
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Folic acid and vitamin B
12
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 B
12
. 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 B
12
.
13
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 B
12
and folic acid had twice the risk of developing Alzheimer’s disease compared to those with normal levels.
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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 B
12
. (For people who eat this way and yet still have high homo-cysteine, daily supplementation with 800 mcg folic acid, 500 mcg vitamin B
12
, and 50 mg vitamin B
6
can be helpful. The methylcobal-imin form of B
12
is far more effective than the cyanocobalimin form.)
It is particularly important for vegetarians and vegans to understand
that adequate levels of vitamin B
12
are necessary for folic acid to effectively carry out its functions. Vegans who do not eats foods fortified with B
12
or take B
12
supplements to ensure they get adequate vitamin B
12
are at significant risk for elevated homocysteine levels.
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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.”
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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 B
12
, folic acid, and vitamin B
6
, 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.
17In 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.
18Studies 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.
19A 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 B
3
) 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).
20A 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.
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Confident and Clear-Thinking
No matter what our age or condition, there are still untapped possibilities within us, and new beauty waiting to be born.
—Dale E. Turner
A
nna Morgan died in 1997, at the age of 102, as one of the most thoroughly studied elders in the history of medical science. When she was 101, her cognitive abilities were studied intensively by scientists conducting the New England Centenarian Study.
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The researchers asked Anna if she would be willing to donate her brain to science so that they could study it.
“But I’m still using it,” she answered with a smile.
Anna Morgan spent her entire adult life helping people all over the world. In the 1920s, she distributed condoms to local farmwives (an illegal activity at the time). During the Great Depression of the 1930s, she collected food for families of the unemployed. In 1952, she was called before the Ohio State Committee on Un-American Activities, who charged her with contempt when she refused to answer their questions.
“They were right,” Anna said, looking back at the age of 101. “I had a very healthy contempt for the Committee.”
In 1959, the U.S. Supreme Court overturned her conviction, citing
the First Amendment. It was a case with profound implications for civil rights.
During her nineties, she wrote more than twelve hundred pages of memoirs, and worked on the successful effort to have a postage stamp issued to honor the black singer, actor, and human rights activist Paul Robeson. On her one hundredth birthday, she testified before Congress. At the age of 101, Anna Morgan was still busy, volunteering for groups such as Mobilization for Survival.
But what most interested scientists was her performance on highly sophisticated brain-function tests. When researchers tested her ability at the age of 101 to sustain attention, they found she was easily able to repeat seven-digit strings of numbers, and to connect long number sequences. When they gave her five-digit strings of numbers and asked her to repeat them backward, she had no difficulty doing so. She could also, when asked to do so, spell words backward.
You may have noticed that short-term memory loss is common among the elderly in the modern world, as is a corresponding diminished ability to recall information that has been recently learned. Scientists have a way of testing for this. They give their subjects six simple words and ask them to repeat the words three times. Then they sit in silence for a minute, after which they again ask the subjects to repeat the words. Anna Morgan had no difficulty doing this.
Researchers next ask their subjects to count backward from twenty, and to recite the alphabet rapidly. And then, to see to what extent distraction has diminished their subjects’ recall, and to see if they have a rapid rate of forgetting, researchers ask the subjects to repeat the list of six words once more. Anna Morgan did all this perfectly.
They tested her visual-spatial capacity (how the brain makes sense of what it sees) and found that she was able to draw even complicated figures very well. They tested her abstract reasoning and conceptualization skills, and got answers they would have expected from a mentally intact person forty years younger. Again and again, with each test performed, Anna Morgan refuted the theory that old people, simply by being old, will have significantly reduced cognitive abilities.