A, shows the body weight profiles for male, female and OVX female C57BL/6 mice fed CR, LF, or HF diets for 20 weeks. Male mice had a greater propensity to gain weight and become obese than female mice (p < 0.05). However, ovariectomy removed the female mice's protection against gaining weight, and in fact, ovariectomized female mice patterned like male mice in their susceptibility to weight gain (p > 0.05). Within male and female mice, after week 10 the body weights were significantly different among all groups (CR vs. LF vs. HF), before then only the CR mice had significantly lower body weights than LF and HF mice at week 5 (p < 0.05). For female vs. male mice (CR male vs. CR female, LF male vs. LF female, HF male vs. HF female) values were significant different at all time points respectively (p < 0.005). However, values were not significantly different between male and OVX female mice (p > 0.005). Percent body fat was determined by DEXA. Abbreviations: 30% calorie-restricted diet (CR), 5% low-fat diet (LF), 35% high-fat diet (HF). B, shows the percent body fat levels in male, female, and OVX-female C57BL/6 mice. Body fat levels between male and female mice were significantly different, with male mice having more body fat in all three diet categories than female mice (p < 0.05). Body fat levels in ovariectomized female mice were almost identical to those of male mice (within each category, male CR vs. CR OVX-female).