Consuming the Food and Drug Administration's recommended daily diet of 2,000 calories does not work for everyone. A 20-year-old woman who weighs 110 pounds, for example, will not need to consume the same amount of calories as a 40-year-old man who weighs 300 pounds, especially if she is trying to lose weight. According to Peggy Stanfield in "Nutrition and Diet Therapy," the caloric intake percentages on labels are based on a 2,000-calorie diet, so they are not applicable for someone who needs greater or fewer calories. To determine how many calories you need per day to lose weight, you will need to solve a few mathematical equations.
Step 1
Determine your basal metabolic rate, or BMR. Your basal metabolic rate is a starting point in determining how many calories your body needs to lose weight, based on your body type, gender and age, but not on activity level --- your BMR is how many calories you would need to consume to stay at your current weight if you never exercised. Write down your weight in kilograms, your height in centimeters and your age on a piece of paper. Then, plug the numbers into the following equation, known as the Harris-Benedict equation, if you are a man: 66 + (13.7 X weight) + (5 X height) - (6.8 X age) = BMR. Plug the numbers into the following equation if you are a woman: 655 + (9.6 X weight) + (1.8 X height) - (4.7 X age) = BMR.
Step 2
Multiply your activity level with your BMR. If you exercise rarely and work at a non-physical job, multiply your BMR by 1.2. If you exercise up to three days a week, multiply your BMR by 1.375. If you exercise up to five days a week, multiply your BMR by 1.55. If you exercise up to seven days a week, multiply your BMR by 1.725. If you exercise every day and have a physically demanding job, multiply your BMR by 1.9.
Step 3
Adjust your caloric intake number to determine how many calories you must consume per day to reach your goal weight. Recalculate the Harris-Benedict equation, this time using the weight in kilograms you would like to be, rather than the weight you are. Factor your activity level in, and this is the number of calories you should consume per day to reach your goal weight.
Step 4
Count your calories. Now that you know how many calories you need per day to lose weight, remember that you must burn 3,500 calories before you will lose 1 pound of fat. This means that you must be consuming 500 calories less a day or burning 500 calories more than your basal metabolic rate and physical activity level combined in order to lose one pound per week.
Tips and Warnings
- Aim to lose about 1 pound per week by eating healthy and consuming fewer calories.
- Talk to your doctor before starting any weight loss regimen.
Things You'll Need
- Paper
- Pencil
- Calculator
Member Comments