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"Living well and getting everything your body needs to build your defences"
The newspapers and other media are rife with reports that this or that
food or chemical or environmental factor, Everything from canaries to
toasters causes cancer. But most reports are given out of context, and
it's easy to lose sight of the big picture and of the scientific progress
that's been made in understanding and preventing cancer.
Cancer
does not kill as many people as heart disease, but it still claims many
lives per year. Four major cancers (lung, colorectal,
breast, and prostate) account for slightly more than half of these deaths.
Some kinds of cancer (stomach, cervical, and uterine) have dramatically
declined, both in incidence and as a cause of death, while
others are rising, or seem to be rising. For example, breast and prostate
cancer may be occurring more often, or may simply be accurately diagnosed
more frequently. In fact, the number of new cases of prostate cancer has
begun to drop, at least for white Australians. Some other cancers appear to
be occurring more frequently because the population is aging.
People often wonder when the "cancer breakthrough" will occur: when will
researchers unlock the secret and find the cure? The dramatic
breakthroughs we all yearn for - a cancer vaccine, perhaps, or a miraculous
cure for all kinds of cancer—may or may not materialize. But enormous
progress has been made, and insight into the origins and causes of cancer
is growing.
Many of us worry too much about possible cancer promoters that are
actually negligible. And at the same time, we may pay too little attention
to simple but effective measures we can take to protect ourselves.
Important measures for preventing cancer are already at hand.
How does cancer occur?
Genetics has something to do with cancer, though the picture is far from
clear. Genes control every aspect of our body chemistry and the growth of
cells; some genes may promote cancer, others may protect against it. There
is a puzzling interplay of environmental, life-style, and genetic factors,
and it's still uncertain where environmental and life-style influences
actually come in to the equation.
Generating energy, which is the basic process of all
life, produces unstable molecules known as free radicals that can damage
genetic material. This is a normal, everyday process, and most damage is
immediately repaired. But sometimes the repair process fails. Exposure to
our own hormones, to infectious organisms that have penetrated our immune defenses, and to environmental toxins can also create free radicals that
scramble genetic codes and eventually damage cells. If cells are damaged,
cell growth may produce tumors rather than copies of healthy cells. It's
estimated that three-quarters of all cancers occur largely because of
external influences, not our genes.
What you can do
1. Give up smoking. Tobacco use causes more cancer here and in the rest
of the world than anything else. The longer you smoke, and the more you
smoke, the likelier it is to be lethal. Besides lung cancer, smoking
increases the risk of cancer of the bladder, cervix, mouth, throat,
pancreas, kidney, and stomach. It may also promote colon and even breast
cancer. About 3 million people die of smoking-related causes every year
around the world, and that number will rise to 10 million in the next
century if the number of smokers continues to increase. Passive smoking
(inhaling other people's smoke) causes thousands of deaths a year.
If all tobacco users in this country quit, total deaths from cancer would
eventually drop by at least one-third. Lung cancer would become a rare
disease, rather than the major cancer killer of both American men &
women that it now is.
2. Eat more fruits, vegetables, and whole grains.
Diet causes about one-third of all cancer cases, almost as many as
tobacco use. Having a diet that consists predominantly of fruits,
vegetables, and grains (the current recommendation is at least
five servings of fruits and vegetables a day) is the most
important
factor currently identified in the
prevention of cancer through diet. The evidence for this is overwhelming: study after
study has confirmed that people who have the highest intakes of fruit and
vegetables have the lowest rates of most cancers. Fruits and vegetables
contain large amounts of antioxidant vitamins (C and E), as well as
folacin, carotenoids, and dietary fiber, which are all important in
preventing cancer. Many phytochemicals (plant chemicals) have been shown
to have cancer-fighting potential in laboratory studies—and many are still
waiting to be discovered.
3. Eat less animal fat. A diet high in animal fat, especially from
red meat, has shown up in several studies as a risk factor for prostate
and colon cancer. A high-fat diet is also suspected of being a factor in
breast cancer, although recent research suggests there is no link.
Countries with high-fat diets do have the highest rates of breast and
prostate cancer, but other factors could be at work.
4. Don't cook meats at very high temperatures, especially over an open
flame. This creates compounds known to promote certain cancers—for
example, polycyclic aromatic hydrocarbons (PAHs), which form when meats
are charcoal-broiled. An occasional barbecue is probably not harmful.
You're better off to steam, braise, bake, poach, stew, or microwave than
to barbecue.
5. Limit you alcohol intake. Moderate alcohol intake can help prevent
heart disease. ("Moderate" means no more than one drink daily for
women, two for men.) But too much alcohol can cause cirrhosis of the liver
and liver cancer. Especially when combined with smoking, heavy drinking
also contributes to cancers of the mouth, throat, and esophageus, for
example. Thus, some experts still say that drinking no alcohol is best.
6. Be active. In the past ten years, studies have suggested that
exercise helps prevent breast and prostate cancer, and there's solid
evidence it can prevent colon cancer. It's hard to say what level of
activity is needed; but moderate activity starting early in a woman's life
seems to protect against breast cancer.
7. Control your weight. Being significantly overweight puts you at
risk for such diseases as stroke and heart disease, and probably also for
some cancers (uterine and postmenopausal breast cancer in women; colon and
prostate cancer in men). No one is sure why obesity might boost the risk
of cancer. Nevertheless, this is still another reason to maintain a
healthy weight.
8. Limit your exposure to the sun. Use a potent sunscreen when you
are in the sun. Cumulative sun exposure is responsible for most skin
cancers, which account for about 2% of cancer deaths.
9. Limit workplace exposure to chemicals. For people who work with
cancer-causing chemicals, such as asbestos, benzene, and formaldehyde,
this is a serious problem. However, extensive exposure to such chemicals
is uncommon among the population at large.
What about pesticides?
Food is a complex mixture of natural ingredients, not all of them benign.
Plants themselves produce pesticides to ward off attack from animals and
micro-organisms. Our bodies are equipped to defend themselves against most
of the potentially harmful elements in foods, just as we have chemical
defences against other kinds of low-level toxins. But it's man-made
pesticides that cause the most worry. Humans have been consuming natural
pesticides for thousands of years, and we may have ways of protecting
ourselves from them, whereas we might be less able to fend off synthetic
chemicals. Much remains to be learned about man made pesticide residues in foods.
Therefore caution is certainly far better than throwing
caution to the wind. Where ever you can consume organic foods.
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