If you want a healthy heart, you have to work at keeping fit — unfortunately most of us don’t. One study found that more than 68 percent of adults are overweight and another 35 percent are obese. Weight management is one of the major keys to help prevent heart disease. You can watch your weight by eating a healthy diet that’s low in salt, sugar, fat, and calories, and rich in fiber, in addition to getting plenty of exercise. “Try to achieve your optimal body weight,” says Watson. (Ask your doctor if you’re not sure what that number is.) Once you reach this weight, try to burn at least as many calories as you consume.