A low-fat diet is usually used to help with weight loss or weight maintenance, and prevention and treatment of heart disease, high cholesterol, high blood pressure, cancer, and diabetes. Many low-fat diets are also vegetarian, although anyone can follow a low-fat diet, whether or not they are vegetarian.

• There are many different kinds of low-fat diets. The most general guidelines are to keep your fat intake at 20 to 30% of your daily calories, and saturated fat to 10% or less of your daily calories.

• Avoid sources of hidden fats by reading the nutrition facts panel on packaged foods to find out the total amount of fat per serving. Steer clear of highly processed low-fat or fat-free foods, which might have as many calories as the regular-fat version, and can lead to weight gain, even though they are labelled as "low fat."

Low-fat = lower on the food chain. Emphasise whole grains, fruits, and vegetables, and avoid higher fat dairy and meat products. See our articles on the Dean Ornish Diet and the Pritikin Diet Program for more low-fat information.