Why Almost Everything You Hear About Medicine Is Wrong

If you follow the news about health research, you risk whiplash. First garlic lowers bad cholesterol, then—after more study—it doesn’t. Hormone replacement reduces the risk of heart disease in postmenopausal women, until a huge study finds that it doesn’t (and that it raises the risk of breast cancer to boot). Eating a big breakfast cuts your total daily calories, or not—as a study released last week finds. Yet even if biomedical research can be a fickle guide, we rely on it.

But what if wrong answers aren’t the exception but the rule? More and more scholars who scrutinize health research are now making that claim. It isn’t just an individual study here and there that’s flawed, they charge. Instead, the very framework of medical investigation may be off-kilter, leading time and again to findings that are at best unproved and at worst dangerously wrong. The result is a system that leads patients and physicians astray—spurring often costly regimens that won’t help and may even harm you.

Ioannidis, 45, didn’t set out to slay medical myths. A child prodigy (he was calculating decimals at age 3 and wrote a book of poetry at 8), he graduated first in his class from the University of Athens Medical School, did a residency at Harvard, oversaw AIDS clinical trials at the National Institutes of Health in the mid-1990s, and chaired the department of epidemiology at Greece’s University of Ioannina School of Medicine. But at NIH Ioannidis had an epiphany. “Positive” drug trials, which find that a treatment is effective, and “negative” trials, in which a drug fails, take the same amount of time to conduct. “But negative trials took an extra two to four years to be published,” he noticed. “Negative results sit in a file drawer, or the trial keeps going in hopes the results turn positive.” With billions of dollars on the line, companies are loath to declare a new drug ineffective. As a result of the lag in publishing negative studies, patients receive a treatment that is actually ineffective. That made Ioannidis wonder, how many biomedical studies are wrong?