Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: MONDAY, February 11, 1991 TAG: 9102090462
SECTION: EXTRA PAGE: E-3 EDITION: METRO
SOURCE: JANE E. BRODY
DATELINE: LENGTH: Medium
So where will it all lead? Surely one knows at least one person who did everything right and still got a dread disease.
Or someone who flouted all the advice, yet escaped intact for 90 or more years.
A true believer in the value of healthful living probably said, "It just isn't fair," but continued to walk the recommended path.
But if one were already resisting the pressure to give up unhealthy habits, then such glaring "injustice" probably strengthened the resolve to live however one pleases and take one's chances.
Before becoming wedded to either course, it makes sense to consider the nature of the advice, its protective potential and the strength of the evidence supporting each recommendation.
Health-promoting habits are not guarantees; they do not offer 100 percent protection, like a vaccine against a disease. Good habits merely weight the odds in one's favor.
If genes predispose a person to developing a particular health problem, one or more of the recommended measures may prevent or delay those genes from taking effect.
Or if one is exposed to some harmful environmental factor, like asbestos or radon, good health habits may bolster the resistance to its deadly effect.
When the habits of large groups of people were matched with chronic ailments and causes of death, those who adhered to health advice were found to be less likely to suffer afflictions like cancer, heart attack, stroke or diabetes.
But what applies to large groups does not necessarily apply to people within those groups.
Furthermore, when the major fatal diseases are considered one by one, the importance of each element in the healthy-life prescription is found to vary.
Smoking does not contribute to breast cancer or diabetes, but it is a major factor in lung cancer or heart attack.
To help people assess the relative value of good health habits to disease prevention, Dr. Gary Williams, director of medical sciences at the American Health Foundation, a health research organization, has ranked the value of the various recommendations in preventing particular diseases, based on thousands of studies among people around the world.
The analysis is not all-inclusive. It does not consider health problems like high blood pressure, osteoporosis and ulcers.
Nor does it consider the preventive value of stress management, eating breakfast regularly, sleeping seven hours a night or other factors.
Furthermore, the individual dietary recommendations in some cases differ from those urged by other major health organizations. The American Health Foundation considers a low-fat diet to derive about 20 percent of calories from fat, a diet high in fiber would provide at least 25 grams of fiber a day, and a diet low in salted foods would include fewer than 2,200 milligrams of sodium each day.
Currently, the average American diet includes nearly twice the fat, less than half the fiber and perhaps twice the sodium of this recommendation.
Williams's analysis indicates that, as far as is known, the two measures with the broadest protective effects are diets low in fat and high in vegetables and fruits.
A low-fat diet (that is, one that includes fewer than 25 grams of fat for every 1,000 calories consumed) is rated highly effective in protecting against cancers of the breast and colon, heart attacks and the onset of diabetes in adults.
Also, a low-fat diet is moderately effective in preventing cancers of the uterine lining, rectum and pancreas and it has a slight benefit against lung cancer.
Eating lots of fruits and vegetables appears to be highly useful in countering cancers of the colon and stomach and offers some benefit in warding off cancers of the breast, endometrium and liver, as well as heart attacks, strokes and diabetes.
Some benefit has also been shown against cancers of the lung, rectum, esophagus, pancreas and bladder.
As for diets rich in fiber, the main demonstrated benefit has been against colon cancer, with modest effects against diabetes and cancers of the breast and rectum.
Despite the hoopla about oat bran and other soluble fibers that are said to lower cholesterol, their role in reducing the risk of heart attacks has yet to be clearly demonstrated, according to Williams.
On the other hand, avoiding salted and pickled foods can be highly effective in reducing the risk of stomach cancer and stroke, moderately beneficial against esophageal cancer and slightly helpful against liver cancer.
by CNB