Figure 1.

Comparison of ad libitum feeding versus chronic calorie restriction (CCR) feeding versus intermittent calorie restriction (ICR) feeding on mammary tumor incidence (%) in MMTV-TGF-α mice. (a) Study 1: intervention started at 10 weeks of age. ICR mice calorie restricted by 50% for 3 weeks followed by 3 weeks of ad libitum refeeding until 80 weeks of age (1 week of refeeding). Calorie intake for ICR and CCR mice reduced ~20%.[41] (b) Study 2: intervention started at 10 weeks of age. ICR mice calorie restricted by 50% for 3 weeks followed by 3 weeks of ad libitum refeeding until either 79 (after final restriction period) or 80 weeks of age (1 week of refeeding). Calorie intake for ICR and CCR mice reduced 11% and 14%, respectively.[42] (c) Study 3: intervention started at 10 weeks of age. ICR mice calorie restricted at 50% for 3 weeks followed by 3 weeks of controlled refeeding (i.e., matched to ad libitum fed mice's intake) until 79 (after final restriction period) or 82 weeks of age (after the final 3 weeks of refeeding). Calorie intake for ICR and CCR reduced ~25%.[43] For each study, the values are all different by Chi square analyses