Obesity paradox in coronary artery disease: national inpatient sample analysis.

Summary: We usually think carrying extra weight is bad for our hearts. But a massive new study of over 3.6 million hospital patients with heart disease found a major surprise. People who were underweight or normal weight were actually more likely to die in the hospital than people who were overweight or obese.

Underweight patients had the highest risk of dying and stayed in the hospital the longest. On the flip side, overweight and obese patients had much lower death rates. Doctors call this the "obesity paradox." It means that for people who already have coronary artery disease, having some extra body weight might somehow protect them and help them survive a hospital stay.