This book (NIH Publication 05-5213) by the National Institutes of Health and the National Heart, Lung, and Blood Institute provides practical, easy-to-use information for losing and maintaining weight. Reaching and maintaining a healthy weight is good for your overall health and will help you prevent and control many diseases and conditions. We know that an increase in weight also increases a person's risk for heart disease, high blood cholesterol, high blood pressure, diabetes, gallbladder disease, gynecologic disorders, arthritis, some types of cancer, and even some lung problems. Maintaining a healthy weight has many benefits, including feeling good about yourself and having more energy to enjoy life. A person's weight is the result of many things-height, genes, metabolism, behavior, and environment. Maintaining a healthy weight requires keeping a balance - a balance of energy. You must balance the calories you get from food and beverages with the calories you use to keep your body going and being physically active. The same amount of energy IN and energy OUT over time = weight stays the same More IN than OUT over time = weight gain; More OUT than IN over time = weight loss. Your energy IN and OUT don't have to balance exactly every day. It's the balance over time that will help you to maintain a healthy weight in the long run. For many people, this balance means eating fewer calories and increasing their physical activity. Cutting back on calories is a matter of choice. Making healthy food choices that are lower in fats, especially saturated and trans fat, cholesterol, added sugars, and salt can help you cut back on calories, as can paying attention to portion sizes. This booklet will provide you with information to figure out your body mass index and weight related risk for disease. It will also give you information on when and how to lose weight, including tips on healthy eating and physical activity, setting weight loss goals, and rewarding your success.