Changes in body composition in mice during feeding and withdrawal of conjugated linoleic acid

Two experiments were conducted. In Experiment 1, 8-wk-old mice were fed con trol diet or diet supplemented with 0.5% conjugated linoleic acid (CLA) to study the effect of CLA on body composition (CLA: 40.8-41.1% c-9,t-11 isome r, 43.5-44.9% t-10,c-12 isomer). The data for CLA-fed mice vs. controls des cribed parallel but significantly distinct responses for both absolute and relative changes in body fat mass (reduced in CLA-fed mice) and for relativ e changes in whole body protein and whole body water (both of which were in creased in CLA-fed mice). In the CLA-fed mice, the effect on whole body pro tein appeared to precede the reduction in body fat mass. In Experiment 2, w eanling mice were fed control diet or diet supplemented with 0.5% CLA for 4 wk (test group), at which time all mice were fed control diet devoid of ad ded CLA. The test group exhibited significantly reduced body fat and signif icantly enhanced whole body water relative to controls at the time of diet change. Time trends for changes in relative body composition were described by parallel lines where the test group exhibited significantly less body f at but significantly more whole body protein, whole body water, and whole b ody ash than controls. Tissue CLA levels declined following the withdrawal of CLA from the diet. In skeletal muscle of mice fed CLA-supplemented diet, the t-10,c-12 isomer was cleared significantly faster than the c-9,t-11 CL A isomer.