Effect of an energy-reduced dietary regimen in relation to adipose tissue cellularity in obese women.

Twenty-eight obese women were divided after arbitrary statistical guidelines obtained from control studies into hyperplastic (increase in fat cell number) (n equal to 10), hypertrophic obesity (increase in average fat cell size) (n equal to 11), and a remaining group (n equal to 7). All these subjects were treated on an outpatient basis with an energy-reduced diet (1,100 kcal/day) until weight decrease failure occurred. The fat cells of the femoral and gluteal regions were larger than in the abdominal region in hypertrophic obese subjects. This regional fat cell size profile was found also in middle-aged and young controls. The hyperplastic obese subjects on the other hand had larger fat cells in the abdominal site. At failure of therapy enlarged fat cells in either of the two obesity groups had decreased to the size of fat cells of controls. Fat cell number remained unchanged. Thus the hypertrophic obese patients ended up with a normal body fat while hyperplastic obese subjects had a pronounced remaining obesity. The results suggest that when the fat cell size in different regions of an individual are known, as well as the total fat cell number, the success of an energy-reduced dietary regimen might be approximately predicted both in terms of remaining total body fat and in regional fat depot decrease.