Food for Life: How the New Four Food Groups Can Save Your Life (16 page)

As we age, we lose much of our immune strength. Skin tests, such as the test that checks for exposure to tuberculosis, often act abnormally in older people, and the loss of immune function is considered normal. As the years go by, more and more of our white blood cells act as T-suppressor cells—that is, cells that turn off immune reactions.
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New evidence shows that beta-carotene can counteract much of this age-related immune loss.
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How much beta-carotene does it take to get these benefits? As little as 30 mg per day—the amount in two large carrots—causes the increase in natural killer cells and T-helper cells.

Although beta-carotene is safe, even in fairly substantial amounts, the best way to get beta-carotene is not in pills, but in the carrots, spinach, kale, and other packages in which nature supplies it. Why? Because we now know that beta-carotene is only one of perhaps two dozen related substances called
carotenoids
that occur naturally in vegetables and fruits, and which have varying degrees of biological activity.

Vitamins C
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and E
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and selenium
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bolster immune function in addition to their antioxidant effects, but the importance of these effects against cancer is not yet clear.

Fats impair immunity, and cutting fat out of the diet helps strengthen the immune defenses against cells that turn cancerous. Researchers in New York tested the effect of a low-fat diet on immunity.
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They put healthy volunteers on a diet that limited fat content to 20 percent, about half the national average. They cut down on all fats and oils, not just saturated or unsaturated fats. Three months later, the researchers took blood samples from the volunteers and examined their natural killer cells. The natural killer cell activity was greatly increased. These cells worked much better when the fat was out of the diet.

Although for heart patients vegetable oils are far superior to animal fats, when it comes to the immune system vegetable oils are no better than animal fats. In experiments, researchers have found that when they infuse soybean oil intravenously into volunteers, their white blood cells no longer work as well,
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and test-tube experiments show similar results.
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Likewise, omega-3 fatty acids, which are found in fish oils, green vegetables, and soybean, flaxseed, and rapeseed oils, also compromise immune
function.
^64–
66
The bottom line is to greatly reduce all fats and oils.

It will come as no surprise that vegetarians have the strongest immune systems. Since 1978, researchers at the German Cancer Research Center in Heidelberg have examined vegetarians. They weighed them (vegetarians weigh less than nonvegetarians); they measured them (their height is the same as nonvegetarians); they measured the vitamin content of their blood, finding more beta-carotene, compared to others. And recently, they tested the strength of their immune systems. They took white blood cells from vegetarians and tested their capacity to knock out cancer cells.
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The vegetarians were compared against nonvegetarians working at the cancer center. Each day, blood samples were taken and their strength to kill cancer cells was checked.

The results were unequivocal. The vegetarians had more than double the ability of their nonvegetarian counterparts to destroy cancer cells. The researchers concluded that the immune muscle of vegetarians comes either from their having double the number of natural killer cells or from each cell having double the killing power. Whichever it is, vegetarians have a defense against cancer cells that is far beyond that of their meat-eating fellows.

The immune power of a vegetarian diet is partly due to its high vitamin content and partly due to its low fat content. There may be other contributors, too, such as reduced exposure to toxic chemicals and animal proteins. Thus, the wrong food choices can weaken our defenses against cancer, but a low-fat menu of grains, vegetables, fruits, and legumes allows the body’s natural power to be brought to bear for greater health.

Not all cancers are the same. Some have a relatively good prognosis, and others have a very poor prognosis. For example, a tumor that is small and has not spread to the lymph nodes or other organs is less dangerous than a tumor that is larger and has spread. (Lymph nodes are pea-size collections of cells near the breast and other organs that are important to immune function.) Hospital laboratories also determine whether a breast tumor has
receptors for estrogen or progesterone hormones. If it does, the tumor is slightly less aggressive than if it lacks receptors.

These prognostic factors are not due to chance alone. Thirty years ago Ernst Wynder of the American Health Foundation in New York observed that, aside from the fact that Japanese women are much less likely than American women to get breast cancer, when Japanese women do get the disease, they tend to survive longer.
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Their improved survival is independent of age, tumor size, estrogen receptor status, extent of spread to lymph nodes, and microscopic appearance of the cancer cells.
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It is not that Japanese women have better health care, because the same pattern has been observed in Hawaii
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and California,
⁷¹
where Japanese women live nearby other ethnic groups and have essentially the same health-care system.

Researchers have begun to look at whether diet plays a role in survival. It does. Our old enemy—fat in foods—rears its ugly head once again. The more fat there is in the diet, the shorter a cancer patient survives. In a Canadian research study, women with cancer were more likely to have lymph node involvement if they had a high fat intake. This effect was found only for saturated fat and only for postmenopausal women.
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Fat seems to have a measurable effect when cancer has spread to other parts of the body,
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and littie or no effect when the disease is localized.
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Researchers in Buffalo, New York, calculated what they believe to be the degree of risk posed by fat in the diet. For a woman who has breast cancer which has spread to other parts of the body, her risk of dying from the disease at any point in time increases 40 percent for every 1,000 grams of fat consumed monthly.
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Of course, for any individual, there are many factors that play a role in survival. These figures were rough estimates drawn from groups of women both pre- and postmenopausal, in order to understand the magnitude of the effect of diet.

Let’s compare three different diets, all of which contain 1,200 calories per day:

• On a low-fat vegetarian diet, about 10 percent of calories come from fat. This type of diet contributes about 13 grams of fat per day, or 400 grams per month.
  

• On a typical American diet, 37 percent of calories come from fat. This means about 49 grams of fat per day, or about 1,500 grams per month.
  

• On a diet with more fat than average—say, 50 percent of calories—fat intake would be 67 grams per day, or 2,000 grams per month.
  

If the researchers’ finding holds, the typical American diet would lead to about a 40 percent higher risk of dying of breast cancer at any given point, compared to the low-fat vegetarian diet, while the high-fat diet would lead to a more than 60 percent increase in risk of dying. These figures do not mean that a woman’s risk of dying in each instance is 40 percent or 60 percent. They mean that the risk is 40 percent or 60 percent higher than it would otherwise have been, assuming the individual is comparable to those studied. If, for example, a person’s risk of dying, say, within five years were 35 percent on a low-fat diet, a typical American diet would boost the risk to 49 percent and the high-fat diet would boost it to 56 percent. This is not an enormous effect, but it is apparently a real one.

Other parts of the diet play important roles. Diets that are high in fiber, carbohydrate, and vitamin A seem to help the prognosis, while alcohol slightly worsens it.
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Patients who have more estrogen receptors on their tumors (which indicates a better prognosis) tend to be those who had consumed more vitamin A.
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For reasons that are not entirely clear, vegetables and fruits, and the vitamins they contain, help keep the cells of the body in better working order—one sign of which, for breast cells, is the presence of estrogen receptors. So vegetables and fruits are not only important in helping to prevent cancer but also in improving survival for those who have cancer.

Higher body weight increases the risk of dying of breast cancer.
^73
,
75
Among postmenopausal women with breast cancer, slimmer women tend to have less lymph node involvement.
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Heavier women have more lymph node involvement, higher rates of recurrence, and poorer survival.
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It also makes a difference where the fat is on the body. One study found that, for reasons that are not clear, women who carry fat on the abdomen tend to have smaller tumors, less node involvement, and higher levels of estrogen receptors than women whose fat is proportionately more on their thighs,
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although abdominal fat is linked to higher risk of other health problems, including heart disease, diabetes, and high blood pressure.

The uterus and ovary, like the breast, are strongly influenced by sex hormones, and one might assume that the factors that improve survival in breast cancer might do the same for cancers of these organs. Unfortunately, aside from a smattering of research papers debating the benefits of assuring that patients get enough calories and the Recommended Daily Allowances of vitamins and minerals, researchers have essentially ignored this issue. Until more information is available, it seems most prudent for those with ovarian or uterine cancer to follow the same diet that helps prevent cancer in these organs and that keeps the immune system in good working order: a low-fat, pure vegetarian diet, with an abundance of vegetables and fruits.

Diet may help improve survival in prostate cancer as well. When pathologists conduct autopsies of men over forty-five years of age who die from accidents or other causes, they find cancer cells in the prostates of about 20 percent of them.
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These men did not know they had cancer and had no symptoms whatsoever. The prevalence of such latent cancers actually varies with location, the lowest rates being in Singapore (13 percent) and Hong Kong (16 percent), and the highest in Sweden (32 percent).
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In most men, the cells never grow into a large tumor, never spread, and never affect life or health in any way. However, just as the prevalence of latent cancers varies from one country to the next, the likelihood that they will turn into symptomatic cancer varies in precisely the same way, suggesting that the same factors that cause cancer cells to form in the first place also encourage them to grow and spread. So while a Swede is twice as likely as a man from Hong Kong to have cancerous cells in his prostate, he is more than eight times more likely to die of prostate cancer.
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A low-fat, high-fiber diet can help eliminate the hormonal aberrations that are known to be linked with prostate cancer, and may help improve survival among those who have the disease. Unfortunately, there has not been enough research in this area to know just how successful dietary change might be.

Anthony J. Sattilaro was president of Methodist Hospital in Philadelphia,
and became perhaps the most famous advocate of the use of diet against cancer. In his best-selling book
Recalled by Life
,
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he raised the question as to whether diet can turn the tide on cancer, and the fact that there was simply not enough information yet available to speak with assurance.

Dr. Sattilaro was a young man when he was found to have prostate cancer. By the time it was diagnosed, it had spread throughout his body. Surgical removal was impossible; there was nothing for him to do but to get his affairs in order.

By chance, he happened to meet some young people who were advocates of macrobiotics, which is essentially a traditional Asian diet including generous amounts of rice and vegetables. There is a wealth of literature drawn from Asian traditional medicine on using diet in dealing with cancer and many other health problems. Although Sattilaro was skeptical, and initially taken aback by the idea of such a radical change in his diet, he felt he had nothing to lose. He began a macrobiotic program with the same rigidity that he had applied to his medical career. And as his book described, his symptoms began to fade. Before long, all trace of the cancer, including that on his X-rays, went away.