This is a very good question and we all must understand the answer so we reduce our frustration and disappointment. There are several reasons why after losing weight quickly in the beginning, the amount of weight loss slows down.
First. If you have lost many pounds by sticking with a very strict diet, the difference from your new weight to your present calorie count is less than the difference between your old weight and your present calorie count. In other words a 150 pound person just can’t lose as fast and as much as a 250 pound person.
Second. There is a theory that a “set point” exists in our brain that attempts to protect our present weight to some degree. In other words, if our weight is 240 pounds at our present calorie intake and energy metabolism level and if we are working to change our weight, our body will somewhat work against us when we move very far away from our present weight. Many bariatricians feel that one of the advantages of the medicines we prescribe is that it allows this “set point” for our weight to be switched to a lower level. This is not yet been proven scientifically, but studies presented at national conferences strongly support this thought.
Third: As we lose weight, initially our weight loss is approximately 75% fat and 25% lean body tissue. As we exercise and perhaps increase our protein intake, we build muscle to replace the lost lean body mass. Therefore, our weight loss changes to primarily fat and we actually may be building our muscle mass. We may lose 6 pounds of fat and gain three pounds muscle resulting in only a 3-pound loss on the scale.
There are many theories to attempt to explain this as well as some flimsy excuses and lack of focus. Our hope is that you will understand that this is an occasional situation and rather than get disappointed and discouraged, rather continue on knowing that it is a small hurdle for those who forge ahead.