How to Interpret Medical Research

It’s a time-honored tradition: Researchers labor for years to establish, say, that an incremental excess of the amino acid isoleucine in the left anterior portion of the liver correlates slightly with increased life expectancy, and the day after the results are announced, tabloid headlines scream “Isoleucine: The Key to Eternal Life!” If you’re the type who adjusts your health regimen according to what you read in the paper, you might first want to think about how to interpret medical research.

Instructions

Difficulty: Easy

1. Take the headlines with a grain of salt. OK, a grain of salt might be bad for you if you have high blood pressure—but it can also be a good way to maintain your electrolyte balance. See what we’re getting at here? By necessity, newspapers and magazines can’t present all the “ifs,” “ands” or “buts” of complex medical research, and tend to boil down results that apply only to a slim section of the population into a useless bromide for all.
2. Understand that medical research is a continuing process. It’s possible for a study of 100 patients that shows a slight benefit of daily doses of vitamin E to be contradicted years later by a study of 1,000 patients of more diverse ages and backgrounds. Medical research rarely produces an unequivocal result that everyone agrees on (with the exception of numerous studies showing that smoking is, in fact, bad for your health).
3. Familiarize yourself with medical protocols. You’ll have an easier time interpreting the health news in your local newspaper if you know the definition of a “double-blind” trial (that’s when neither the patient nor the physician knows whether medicine or a placebo is being administered) or what it means to belong to the “control” group (these are the patients who do not receive the treatment in question, and are compared against treated patients).
4. Know that it’s difficult to separate causes from effects. To return to the fictional example above, it’s not logical to say that an excess of isoleucine in liver tissue is directly responsible for increased longevity. Reputable scientists know that the reverse can be the case: perhaps people with increased longevity have, as a consequence of their metabolism, increased levels of isoleucine in their livers. If this is the case, high-dosage isoleucine therapy would probably be worthless, or even dangerous.
5. Embrace the “placebo effect.” Research physicians have long been bedeviled by the tendency of patients to “will” themselves into good health simply by believing they’re taking a brand-new medication (or vitamin supplement). Medical trials are carefully designed to account for the placebo effect, but ordinary folks aren’t so careful—which is why you should be skeptical when your cousin in Dubuque raves about his zinc supplements.