On the other hand, just because a study was conducted at an elite university
doesn’t mean it’s the gospel. Recently, the National Institutes of Health National
Cholesterol Education Program (NCEP) made bold new recommendations for
taking cholesterol-lowering statin drugs to reduce the risk of heart disease.
Those studies are now under review, however, because, among other reasons,
scientists brought to light that eight of the nine members of the panel making
the recommendations had undisclosed financial ties to makers of statin drugs.
Don’t assume cause and effect
If a study says that eating oat bran is linked to or is associated with low
blood-cholesterol levels, this doesn’t mean eating oat bran causes low cho-
lesterol levels. Maybe the oat bran eaters are health-conscious and get a lot
of exercise. You have to ask, “Was it the oat bran or the exercise?” Also, take
any individual study with a grain of salt; when several studies back certain
findings, you can be far more sure of their validity.
Look for comparison groups
One magazine article we came across touted the benefits of a powdered food
replacement. As evidence, the article cited a study of 28 overweight women
who cut their daily calories by taking the powder twice a day instead of food;
the subjects also exercised three times a week. After two months, the article
stated, “an astounding 100 percent” of the women lost weight and felt better.
Astounding? Any overweight person who cuts calories and exercises regularly
is going to see results after two months. For the study to have any validity,
the researchers should have compared the group taking the powder with a
control group of similar subjects who ate the same number of calories and
followed the same exercise program but didn’t use the product.
Do some math
You often read that a certain habit “doubles” the risk of death or “increases
the risk of disease by 50 percent.” These figures can be misleading. In a study
that followed 115,000 nurses for 16 years, researchers found that gaining 11
to 18 pounds in middle age raised the nurses’ heart disease risk by 25 percent.
But the number of deaths in the study was so small that a 25 percent increase
would mean the difference between 10 deaths in 10,000 people and 12 or 13
deaths in 10,000.
Appendix: Educating Yourself 387