Remember the notorious statistic from the '80s claiming that single women over 40 have a greater chance of getting offed by a terrorist than marching down the aisle? Turns out it was as bogus as Eva Longoria's sex tape. The report was based on outdated information and failed to take into account that women were waiting longer to swap rings. Yet the media blitz proved that even skewed stats can take on a life of their own.
"It's remarkably easy to exaggerate numbers or present them in a misleading way," says Lisa Schwartz, M.D., associate professor of medicine at Dartmouth Medical School. To get perspective, she says, read the fine print of medical studies (results based on a 2-week study of 5 people are not exactly conclusive). And consider something called "absolute risk": your overall chance of a certain thing happening to you. Let's say, hypothetically, a study finds that drinking beer doubles your risk of brain cancer. Sounds serious--but if your overall risk of getting the disease is only one in 1 million, then doubling that risk suddenly doesn't seem so scary. If trying to decipher all the headlines has your head twirling, read on. We've taken a few of the latest studies and separated the facts from the medical myths.
The Pill causes breast cancer!
The claim: Popping birth control pills before your first pregnancy increases the risk of breast cancer in women under 50 by 44 percent.
The reality: For adults under age 50, overall, only about 69 women per 100,000 will get breast cancer.
The takeaway: If you take the Pill, your chance of getting breast cancer between the ages of 20 and 49 is less than a tenth of 1 percent. And other studies have found that Pill users are less likely than nonÃ¢â‚¬“Pill users to develop colon or ovarian cancer.
A new drug lets you keep weight off forever!
The claim: Injections of the hormone leptin help you keep pounds off by fooling your body into thinking you never lost the weight, so you continue to torch calories.
The reality: The study was done on 10 people over 10 weeks.
The takeaway: "You should be wary of any study with fewer than 100 participants," Dr. Schwartz says. "Data from longer studies [years, not months] are more reliable."
Prozac could harm your unborn baby!
The claim: Taking antidepressants when you're pregnant adds to the risk of birth defects.
The reality: That's partly true--taking selective serotonin reuptake inhibitors (SSRIs) has been associated with some abnormalities. But those problems are so rare to begin with that the increase in risk is negligible.
The takeaway: Any pregnancy carries about a 3 percent risk of birth defects; if you take an antiÃ‚Âdepressant, you add to that risk by less than one percent.
Coffee and cigs protect against disease!
The claim: Smoking and drinking java may lower your risk for Parkinson's disease.
The reality: This finding came from what's known as an observational study, meaning researchers were looking for common denominators among Parkinson's patients as compared with non-Parkinson's sufferers. In this case, subjects without the disease were more likely than their sick counterparts to smoke and swig Starbucks. That hardly means that those habits prevent Parkinson's.
The takeaway: In a study like this, it's impossible to conclude whether the caffeine-and-nicotine habit really kept people healthy or the participants had something else in common that staved off the disease.