Body weight was determined on the 7th day of each week and data are means ±s.e.m. of values from 7 (chow-fed males), 20 (MHF diet-fed males), 14 (chow-fed females) or 28 (MHF diet-fed females) mice. One-way ANOVA for repeated measurements: A, F1,25 = 6.725 P = 0.0157. *P < 0.05 versus chow-fed mice, by unpaired t test; B, F1,40 = 0.854, P = 0.361.