The 50% myth

Nutrition Action Healthletter, Nov, 2003

Only half of all heart attacks are caused by known risk factors, like smoking, high cholesterol, diabetes, and high blood pressure. Or so people say. It's not clear where that myth started, but two new studies show that it's flat-out wrong.

One team of researchers examined three studies that tracked more than 386,000 people for 20 to 30 years. A second team analyzed data on more than 122,000 people in 14 clinical trials. The conclusion: Between 80 and 90 percent of patients who were eventually diagnosed with heart disease--and more than 95 percent of patients who died of heart disease had at least one of the major risk factors.

What to do: Don't smoke. Use diet, exercise, and (if necessary) drugs to keep your cholesterol, blood pressure, blood sugar, and weight at healthy levels.

J. Amer. Med. Assoc. 290: 891, 898, 947, 2003.