We know that yo-yo dieting, repeated gaining and losing weight is very common place. When we attempt to lose weight by only restricting caloric intake, we will typically lose both body fat and lean muscle tissue. This can adversely affect our metabolism in a way that can potentially lead to continued weight gain. The reason for this is that our daily caloric requirements (the amount of calories needed to maintain current weight) is dependent upon the percentage of body fat we carry. Body fat requires fewer calories to maintain than does lean muscle tissue. Consider the example below:
Jane is a 5’4” female who weighs about 140 pounds. Forty pounds of her total weight is body fat, so her body fat percentage is 29%. Jane requires about 1900 calories per day to stay at her current weight. She goes on a diet to lose 20 pounds and she does not exercise. (Had Jane gone to http://www.thehypnosisoasis.com she would have received a free Action Guide with her hypnosis recording that would have advised her differently.) Now her total weight is down to 120 pounds. She lost 10 pounds of body fat and 10 pounds of muscle, so her body fat percentage is 25% and she now requires about 1700 calories to maintain her new current weight. Over the course of several months she regains the 20 pounds that she had lost, but since she hasn’t been exercising all of those pounds are body fat. Now she’s back at 140 pounds and her body fat percentage is 36 percent or 7 percent more than when she previously weighed 140 pounds. Because of the higher body fat percentage she requires 1800 calories per day to maintain her old weight. This is 100 calories per day fewer than before, so if she eats the same as she did previously she will gain even more weight! The table below shows these comparisons.
Before Dieting After dieting After re-gaining lost weight
Total Wt 140 120 140
Lean Weight 100 90 90
Body Fat Weight 40 30 50
% BF 29% 25% 36%
Approx Daily 1900 1700 1800
So you see, dieting without exercise can really make it difficult to lose weight and keep it off. Another way to look at this is to think of body fat as fuel and muscle as a furnace. A bigger or more efficient furnace can burn more fuel.