If you want to lose weight, you need to eat less food, right? Wrong. When you cut back on the amount of food you eat, you may actually stimulate your appetite, causing you to eat more than usual rather than less. Obviously, this makes losing weight difficult if not impossible. So how is it possible to lose weight without eating less food? The answer is to eat fewer calories, not less food, and this article shows you how.
Calories
No matter what their claims, all weight-loss diets are based on eating fewer calories than your body needs to maintain its weight. It is impossible to lose weight without eating fewer calories. While exercise is effective at helping to maintain any weight loss achieved through diet, it takes an enormous amount of exercise to burn enough calories to lose even one pound. Eating fewer calories, however, is doable.
So what exactly are calories and where do they come from? The technical definition of a calorie is the amount of energy it takes to raise one gram of water one degree Celsius. In more practical terms, calories from food are what give your body energy. In fact, you may hear the calories in food referred to as the energy in the food.
In addition to calories, your body needs certain essential nutrients to function well. There are six essential nutrients: protein, carbohydrate, fat, vitamins, minerals, and water. Only protein, carbohydrate, and fat provide calories. Vitamins, minerals, and water provide no calories, but they assist your body in processing the calories you consume. The purpose of eating a balanced diet that includes foods from each food group (vegetables; fruits; dairy products; meat, fish, poultry, and other high-protein foods; grains; and fats) is to get enough of all of the nutrients you need every day.
Although protein, carbohydrate, and fat all provide calories, they don’t all provide the same number of calories. There are 4 calories in one gram of protein, 4 calories in one gram of carbohydrate, and 9 calories in one gram of fat. This explains why high-fat foods are also high-calorie foods.
Most packaged foods list the total number of calories per serving, but if you didn’t know the total number of calories, you could calculate it if you knew the number of grams of protein, carbohydrate, and fat.
Weight gain or loss
Your body needs a certain number of calories every day, whether or not you perform any physical movement. That’s because your heart, brain, lungs, and other organs are at work all day long, and they require calories to function. Researchers have come up with a number of equations to figure out how many calories are needed simply to maintain basic bodily functions. This is sometimes called the basal metabolic rate (BMR). The following are called the Mifflin–St. Jeor equations:
- For men, BMR = 10 x weight + 6.25 x height – 5 x age + 5
- For women, BMR = 10 x weight + 6.25 x height – 5 x age – 161
These equations require your weight in kilograms, height in centimeters, and age in years. To calculate your weight in kilograms, divide your weight in pounds by 2.2. To calculate your height in centimeters, multiply your height in inches by 2.54.
Your calorie needs also depend on how active you are. To determine your total daily calorie needs, multiply your BMR by one of the following numbers, according to your usual activity level:
- Sedentary: 1.3
- Lightly active (walking or standing but no formal exercise): 1.4
- Moderately active (some exercise): 1.5
- Very active (walking and exercise): 1.6
- Extra active (very hard daily exercise or sports, a physically active job, or training two times a day): 1.8
Also in this article:
Determining Energy Density
Energy Density of Foods
