There is a simple formula to determine what your ideal body weight (IBW) should be.
Once you know that weight, you can calculate the amount of fuel, or calories, needed to maintain it. A factor of plus or minus 10 percent in the following formulas considers different body types, muscle mass, and bone structure, so don't be too concerned if your body weight falls a little outside the given range. The general guidelines follow.
If you are a man, give yourself 106 pounds for the first 5 feet of height and an additional 6 pounds for each inch over 5 feet. For example, if you are 5 feet 10 inches, your body weight should be 106 plus 60, or 166 pounds. With the plus or minus 10 percent factor, the range is 149 to 183 pounds.
If you are a woman, give yourself 100 pounds for the first 5 feet of height and an additional 5 pounds for each inch over 5 feet. Subtract 5 pounds for each inch under 5 feet. For example, if you are 5 feet 6 inches, your body weight should be 100 plus 30, or 130 pounds. With the plus or minus 10 percent factor, the range is 117 to 143 pounds. Realize that most women in American society want to weigh 10 to 15 percent less than their ideal body weight. This can be a very unhealthy situation as we discuss in Eating Disorders.
If you find that your weight is more than 10 percent outside the recommended range, it would be a good idea to visit your doctor for a physical.