Effects of dietary fat content on adiposity during energy restriction in genetically obese rats

The effects of the amount of fat provided in a restricted diet on weight lo ss and body composition were studied in this work. Lean male (Fa/?) Zucker rats were fed a control diet ad libitum. Obese (fa/fa) Zucker rats were div ided into three groups: one group was fed a control diet ad libitum and the other two groups were fed 75 cio energy-restricted diets, which provided 1 0 or 50 % of calories as fat. After 4 weeks, energy restriction normalized body weight but not body composition in the genetically obese rats. Reducti ons in adipose tissue weights and adipocyte size, without changes in the ce llularity, were observed. Differences only reached statistical significance in subcutaneous adipose tissue. A standard fat content in the diet induced the same fat-free mass reduction as a higher amount of this macronutrient, but a greater body fat reduction. This suggests that the restriction of di etary fat, as well as energy, is necessary to achieve dietary management in obesity. (C) Inra/Elsevier, Paris.