Eat less, exercise more. If only it were that simple! As most dieters know, losing weight can be very challenging. As this report details, a range of influences can affect how people gain and lose weight. But a basic understanding of how to tip your energy balance in favor of weight loss is a good place to start.
Start by determining how many calories you should consume each day. To do so, you need to know how many calories you need to maintain your current weight. Doing this requires a few simple calculations.
First, multiply your current weight by 15 — that's roughly the number of calories per pound of body weight needed to maintain your current weight if you are moderately active. Moderately active means getting at least 30 minutes of physical activity a day in the form of exercise (walking at a brisk pace, climbing stairs, or active gardening). Let's say you're a woman who is 5 feet, 4 inches tall and weighs 155 pounds, and you need to lose about 15 pounds to put you in a healthy weight range. If you multiply 155 by 15, you will get 2,325, which is the number of calories per day that you need in order to maintain your current weight (weight-maintenance calories). To lose weight, you will need to get below that total.
For example, to lose 1 to 2 pounds a week — a rate that experts consider safe — your food consumption should provide 500 to 1,000 calories less than your total weight-maintenance calories. If you need 2,325 calories a day to maintain your current weight, reduce your daily calories to between 1,325 and 1,825. If you are sedentary, you will also need to build more activity into your day. In order to lose at least a pound a week, try to do at least 30 minutes of physical activity on most days, and reduce your daily calorie intake by at least 500 calories. However, calorie intake should not fall below 1,200 a day in women or 1,500 a day in men, except under the supervision of a health professional. Eating too few calories can endanger your health by depriving you of needed nutrients.
Meeting your calorie target
How can you meet your daily calorie target? One approach is to add up the number of calories per serving of all the foods that you eat, and then plan your menus accordingly. You can buy books that list calories per serving for many foods. In addition, the nutrition labels on all packaged foods and beverages provide calories per serving information. Make a point of reading the labels of the foods and drinks you use, noting the number of calories and the serving sizes. Many recipes published in cookbooks, newspapers, and magazines provide similar information.
If you hate counting calories, a different approach is to restrict how much and how often you eat, and to eat meals that are low in calories. Dietary guidelines issued by the American Heart Association stress common sense in choosing your foods rather than focusing strictly on numbers, such as total calories or calories from fat. Whichever method you choose, research shows that a regular eating schedule — with meals and snacks planned for certain times each day — makes for the most successful approach. The same applies after you have lost weight and want to keep it off. Sticking with an eating schedule increases your chance of maintaining your new weight.
Some people focus on reducing the fat in their eating plan because, at 9 calories per gram, fat by weight contains more than twice as many calories as carbohydrates or proteins (4 calories per gram). By substituting lean cuts of meat for fatty ones, avoiding high-fat packaged foods and snacks, and refraining from fat-rich products such as butter and partially hydrogenated fats, you can cut out dozens or even hundreds of calories per day. On the other hand, many people mistakenly think that cutting fat always means cutting calories. Some fat-free foods actually contain more calories than the regular versions because manufacturers use extra sugar to make up for the flavor lost in removing the fat. Moreover, low-fat or nonfat foods are not low-calorie if you consume them in large quantities.
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