Putting the balance in a balanced diet

If a healthy diet can help prevent illness and promote a longer, more active life, does that mean there are foods you should never eat?

No. But there are definitely some you should stay away from whenever possible.

If you crave an ice cream sundae, treat yourself to a small one. But don't make it a daily event. If you help yourself to the chips and guacamole at your neighbor's pool party, choose healthier snacks at home. An occasional dietary indulgence isn't harmful.

But Harvard nutrition experts recommend that you keep certain foods to a bare minimum. Why? Research strongly shows that consuming these particular foods regularly increase your risk of developing serious illnesses including heart disease, hypertension, diabetes, and even cancer. Here are three of the biggest offenders.

1. Sugary beverages. Sugary drinks are a major contributor to the obesity epidemic in the United States. Being overweight raises your likelihood of developing type 2 diabetes, heart disease, arthritis, and certain cancers. Research cites soft drinks and other sugar-sweetened beverages as the primary source of added sugar in the American diet and a major contributor to weight gain. In fact, drinking just one 12-ounce can of a sugar-sweetened soft drink daily can add 15 pounds in a year. These beverages offer virtually no nutritional value and pose a big risk to health.
2. Processed foods with trans fats. Cookies, snack cakes, doughnuts, pastries, and many other treats are hard to pass up, but they, too, are at the epicenter of the modern food crisis because the commercially prepared versions are high in trans fats. This type of fat increases the risk of heart disease. These products are also usually packed with refined carbohydrates, added sugar, and salt.
3. Processed and high-fat meats. Shun the cold cuts and "pigs in a blanket" when snacking. Head instead for the vegetable plate. The balance of the evidence confirms that processed meats like bacon, ham, pepperoni, hot dogs, and many lunch meats are less healthy than protein from fish, skinless chicken, nuts, beans, soy, and whole grains. Eat red meat only now and then, and choose the leanest cuts.

For more on developing and maintaining healthy eating habits, buy Healthy Eating, a Special Health Report from Harvard Medical School.