Health Topics for Nutrition

Diet, exercise, and losing weight

Practicing appropriate habits of diet and exercise is essential to losing weight and keeping it off permanently. Healthy eating cannot be a part-time or temporary thing. Making healthy decisions about what to eat each and every day includes striving for moderation and variety. Fad diets that recommend eating only certain foods do not work for long-term weight control. Leaving exercise out of the equation for healthy weight loss and weight maintenance increases the risk for lifestyle-related diseases.

Even though total dietary fat intake has dropped over the last decade, the rates of obesity have increased steeply. So what makes people fat? Is it genetics, an energy imbalance, or the foods we eat? The simple answer is an energy imbalance over a long period of time. This involves eating too many calories and not getting enough physical activity. As a result, more calories are converted to and stored as fat instead of being burned for fuel. The cause of energy imbalance for each person is directly related to a combination of the person's behaviors, environment, and genetics.

As simple as an energy imbalance might seem, there are other factors that complicate and contribute to being overweight and obesity. Genetics may increase one's susceptibility for getting fat, especially when combined with an abundant food supply or not enough physical activity. Environmental conditions can shape health decisions regarding activity and eating. Examples include having to drive to work because the distance is too far to walk or not having nutritional food choices at home or school.

Physical activity is crucial to preventing the gain of excess body fat, losing fat, and keeping it off permanently. Regular physical activity is good for overall health. It contributes to healthy bones, joints, and muscles, reduces falls among the elderly, helps relieve arthritis pain, and decreases the risk for lifestyle-related diseases, such as diabetes and heart disease.

Physical activity does not have to be strenuous to be beneficial. Adults should get at least 30 minutes of moderate aerobic exercise most days of the week, preferably daily. (Children need at least 60 minutes a day.) Doing less than this will minimize your health benefits. Moderate aerobic exercise is generally defined as requiring about as much energy as walking 2 miles in 30 minutes. Simply walking about 2,000 steps a day can burn 100 calories and prevent the average 2-pound weight gain Americans have each year. Exercising can be lots of fun, especially when it includes doing activities like swimming, jogging, cross-country skiing, tennis, aerobics, playing Frisbee, biking, and dancing. Even performing activities like gardening, yard work, and household cleaning chores will burn off excess calories.

Calorie consumption plays a major role in what makes people fat. The conveniences of having fast food restaurants, pre-packaged foods, and soft drinks affect our food choices and are likely to be high in fat and calories. Large servings also increase caloric consumption. People who do not know the basics about nutrition or understand food labels are less likely to make healthy food choices.

Carbohydrates, proteins, and fats are the major nutrient components of the diet. Carbohydrates and proteins provide 4 calories per gram, while fats contribute 9 calories per gram. Most Americans follow meal plans that are much too high in fat. A diet low in fat will reduce the risk for getting certain diseases and help maintain a healthy weight. To lower fat intake, choose plenty of whole grain products, vegetables, and fruits that provide needed vitamins, minerals, fiber, and complex carbohydrates. Food labels identify the amount of calories and nutrients per serving.

The National Academy of Sciences makes the following daily calorie recommendations:

• 1,600 calories is about right for many sedentary women and some older adults
• 2,200 calories is about right for most children, teenage girls, active women, and many sedentary men (Women who are pregnant or breastfeeding may need somewhat more.)
• 2,800 calories is about right for teenage boys, many active men, and some very active women

Keep the fat content of your foods to 30 percent or less. The total grams of fat for a 1,600 calorie diet would be 53, for a 2,200 calorie diet the total would be 73, and for a 2,800 calorie diet the total would be 93. Therefore, for a 30 percent fat diet, 837 calories of a 2,200 calorie diet may be fat calories. Counting fat grams has become popular. To determine the fat in the food you eat in terms of fat grams, read the food package label. It will tell you how many grams of fat and what kinds of fats are in each serving.

Remember, simply controlling grams of fat consumed daily does not necessarily result in weight loss. Total calories that you consume still count. Combining a low fat diet with moderate caloric intake and exercise promotes successful weight loss and healthy weight maintenance.

Last Reviewed 2005

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.

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