Weight loss occurs when you expend more calories than you consume each day. While this seems simple, it turns out that there are many ways calories are used by the body. In general, since fat is nothing more than stored energy, the way to lose fat and weight is by consistently taking in fewer calories than are burned over the course of each day.
Significance
A calorie is a unit of energy--all body cells need energy in the form of calories to maintain normal function. Calories in excess of the body's daily requirements are stored in the form of glycogen in the muscles and liver or, more frequently, as fat. As a result of this fat-storage mechanism, consistently over-consuming calories leads to gaining body fat and weight. On the other hand, when fewer calories are consumed than required, the body pulls the deficit from energy stores, consuming fat in the process. Consistent under-consumption of calories therefore leads to losing body fat and weight.
Caloric Expenditure
According to Exercise Prescription, an online fitness and health website, there are many categories of caloric expenditure, some of which can be manipulated to increase the number of calories burned each day. Routine daily activity, such as moving about at home or on the job, burns calories. As a result, increased non-exercise activity can help to produce weight loss. Physical exercise is also important in producing a caloric deficit. The U.S. government recommends 30 minutes or more of physical activity on most days.
Calculating Calories Burned
While calculators can give you an idea of how many calories you might need in an average day, significant exercise may necessitate a more precise calculation of the calories burned. The Mayo Clinic has a table of exercise types and calories burned per hour available on the Internet (see Resources). For individuals looking to meet a particular caloric deficit each day, this table makes it easier to meet fitness goals.
Calculating Calories Required
Factors including gender, age, weight, and activity level all affect the number of calories each person will require to meet her energy needs in a day. There are a number of calorie requirement calculators available online (see Resources). The Mayo Clinic provides a calculator designed to suggest calories required to maintain weight, while the USDA MyPyramid calculator makes suggestions for calories required to lose weight.
Calories and Fat
According to the Mayo Clinic, 1 lb. of fat contains 3,500 calories. Mayo recommends shooting for a caloric deficit of 500 calories per day, leading to a weekly deficit equal to the caloric content of 1 lb. of fat. The Mayo Clinic provides the disclaimer that caloric deficit from reduced intake alone is not the most effective weight-loss technique: "Exercise along with cutting calories helps boost your weight loss."
Member Comments