Not only is a healthy diet vital for proper growth and function, but scientists now know that it can affect your chance of developing many diseases. A healthy diet helps prevent heart disease; some doctors believe that a very low-fat diet can actually reverse heart disease. What's more, there's a growing theory that certain foods may reduce your risk of various cancers, including breast cancer. Basically, it's advised that women eat mostly fruits and vegetables, whole grains, and fish. Restrict fat to 30 percent or less of daily calories, and avoid polyunsaturated and saturated fats. Aside from fish oil, olive oil is the best choice; canola oil is acceptable. Limit your intake of foods with a high glucose or sugar content. Also, limit alcohol - even one drink a day is thought to raise your risk of breast cancer. Garlic is the most powerful antioxidant - use it freely in your cooking. Supplements may be the only way to get enough of substances like fish oil and indole-3 carbinol (IN-dole 3 CAR-bih-nol), found in the family of vegetables that includes broccoli, cabbage, and cauliflower. However, it's important to realize that taking supplements is never as good as eating the actual food; in fact, overdosing on supplements can be harmful. Pregnant women have special needs, and should get medical advice before making dietary changes. For more information on eating right, talk to your doctor.