Weight loss boils down to pure economics. If calories burned are greater than calories consumed, you will lose weight. If calories burned are less than calories consumed than you will gain weight. There is no escaping it. Individual differences come into play when you have a lower metabolism, but the numbers still apply. A lower metabolism simply means you burn less calories under normal conditions, which makes you more susceptible to weight gain, but as long as you consume less calories than you burn, you can lose weight.

### Things You'll Need

- Scale

- Tape measure

Measure your current weight and height. Your weight should be measured in pounds, and your height measured in inches. You also need your age in years.

Calculate your basal metabolic rate (BMR), which is the amount of calories your body requires, even at rest. The calculation is different between men and women, so use the appropriate formula:

Male BMR = (10 x Weight) + (6.25 x Height) - (5 x Age) + 5 Female BMR = (10 x Weight) + (6.25 x Height) - (5 x Age) - 161

As an example, a 150 pound, 66 inch, 40-year-old mail would require 1,718 calories per day at rest. A female with similar measurements would require 1,552 calories per day at rest.

Add any strenuous activities from the day by referencing the calories burned during such activities. Many online resources offer such lists (see resources). As an example, if the male from the example lightly cycled for an hour, he would add approximately 422, resulting in a total of 2,140 calories burned in that day.

Tally all the calories consumed during the day and add them together. Calories are usually listed on food items, or you may reference them online (see resources). As an example, if you ate three meals totaling 800, 600 and 600 calories, respectively, then your total calories consumed would be 2,000.

Subtract the amount of calories burned from those consumed. If the result is a negative number, then you are on the road to weight loss. This is called having a calorie deficit. If the number is positive, then you need to adjust your eating habits and/or activity to create a deficit, because continuing as you are will cause weight gain. In the male example, you would subtract 2,000 from 2,140, resulting in -140, a calorie deficit.

Repeat this calculation every day for a week or more and average the results to acquire a more accurate estimation. If you tracked your calories for a whole week, you would add all the figures and divide by seven. As an example, if you calculated +100, -600, -300, +300, -600, -400 and +100, then you would divide -1,400 by 7, giving you an average of -200. This means that on average, you are losing 200 calories per day.

Divide 3,500 by your calorie deficit to calculate your weight loss rate. In the example, 3,500 divided by 200 tells, gives you 17.5. This means that you lose one pound of body fat every 17.5 days, or slightly less than two pounds per month. If the average you had calculated was a positive number, then this would be your rate of weight gain.