DIETARY-FAT AFFECTS WEIGHT-LOSS AND ADIPOSITY DURING ENERGY RESTRICTION IN RATS

This study examined the effect of dietary fat during food restriction on weight loss, body composition, and adipose tissue lipoprotein lipas e activity (ATLPL). Rats previously fed a high-fat diet were divided i nto four groups. One group served as baseline controls. The other thre e groups were fed diets of 12%, 28%, or 45% fat, restricted (R) in amo unts to equal 75% of their previous ad libitum energy intake. After 10 wk, body weight loss and reduction of adiposity were significantly le ss in the 45%-R group compared with the 12%-R group (weight P < 0.05; adiposity P < 0.01). Rats fed restricted amounts of the high-fat diet (45%-R group) retained adiposity equivalent to baseline control rats. ATLPL activity was increased in the 45%-R group compared with baseline control rats. Further studies are needed in humans, but these results suggest that body composition will not be normalized with reduction o f energy intake unless dietary fat is also reduced.