When it comes to heart health, theres no better food than fish. Fish are a great source of omega-3 fatty acids, which lower triglyceride levels and help prevent blood clots and arrhythmias. Their anti-inflammatory properties inhibit the growth of arterial plaque. "We think thats why a diet high in omega-3s can reduce the risk of recurrent heart attacks in people with coronary artery disease," says Cleveland Clinic dietitian Melissa Ohlson, MS, RD, LD. Studies also have shown that omega-3s can help fight cancer, depression, and age-related mental decline.