Page 1 of 3 | Next page

FAQs (Frequently Asked Questions)

Every time I go on a low calorie diet and exercise, I never seem to lose any weight. Is it because I have a very efficient metabolism?

This is a very common problem that was addressed in a 1992 scientific study (Lichtman, et. al. Discrepancy Between Self-Reported and Actual Calorie Intake and Exercise in Obese Subjects. NEJM 327:1893-98 [December 31], 1992). In this study, sophisticated techniques to measure actual calorie intake and exercise were utilized to compare to the reported calorie intake and exercise in individuals who reported diet-resistant obesity. To quote the conclusion, “...the failure of some obese subjects to lose weight while eating a diet they report as low in calories is due to an energy intake substantially higher than reported and an overestimation of physical activity, not to an abnormality in thermogenesis (calorie burning)." The dietary resistance that these individuals reported was related to a misperception in calorie intake, exercise expenditure, or both. There was no conscious deception on the part of the subjects.

Does this mean obese individuals do not have a more efficient metabolism?

Absolutely NOT. Obesity is a metabolic disorder, just like diabetes or elevated cholesterol . Very small differences in metabolic rate can, over a period of years, become manifest as a major difference in weight. What the above study says is that obese individuals are like the rest of humanity -- not always aware of what they are doing (like driving down the freeway and realizing you missed your off ramp).

Will liposuction assist with weight reduction? Will it help for the medical complications from obesity?

Liposuction is primarily a cosmetic procedure where localized areas of fat are removed through a suction cannula. The amount of fat removed is generally in the 5-7 lb. range. It is NOT considered a treatment for obesity. Incidentally, when fat is removed surgically, there is a tendency for the body to attempt to replace the "missing" fat tissue. It appears to involve hormones produced by fat tissue.

Sometimes, large amounts (20 lbs.) are removed with liposuction with the thought that it will improve the medical complications from obesity. Unfortunately, this doesn't happen; the high blood pressure, elevated cholesterol, and elevated blood sugars are not improved. These conditions are associated with internal fat, not the fat removed by liposuction.

What is a "protein-sparing modified fast?"

The body is composed of protein, carbohydrates, and fat tissue. In the treatment of obesity, one would like to (ideally) lose only the fat tissue and not lose any lean body mass (protein tissues, such as muscle, or internal organs such as the heart). Whenever an individual loses weight with any diet, there is always some loss of lean body mass. The loss of lean body mass is generally more pronounced with more severe caloric restriction. In a protein-sparing modified fast, calorie intake is generally less than 900 (kcal)/day. However, loss of lean body mass is minimized by maintaining an intake of 70 to 90 grams/day of high-quality protein. These diets are also known as Low Calorie Diets (LCDs) if they contain at least 800 kcal/day or Very Low Calorie Diets (VLCDs) if they contain less than 800 kcal/day. These diets are frequently liquid diets (given the requirements of low-calorie and high-protein content) and should be medically supervised in all individuals. Examples of commercially available LCDs and VLCDs include Optifast, Medifast, and HMR.

Page 1 of 3 | Next page