Losing and regaining weight repeatedly may be dangerous for overweight heart patients.

A new study says heart attacks, strokes and early death were more common in patients whose weight changed the most over four years.

For some patients, weight changes might have reflected yo-yo dieting, which some previous studies have suggested may be unhealthy for people without heart problems. That means a hefty but stable weight might be healthier than losing and repeatedly regaining extra pounds.

Experts say more research is needed on potential risks for people who’s weight goes up and down.

You can read about the study in the New England Journal of Medicine.