Fig. 1.
Effect of chronic caffeine intake (1 g/l) on insulin sensitivity in 3-, 12-, and 24-month-old rats, determined by ITT, expressed as constant for glucose disappearance (KITT). Values represent the mean ± SEM; values without caffeine represent the mean of 8–12 experiments; values with caffeine represents the mean of 8–11 experiments. **p < 0.01, ***p < 0.001, compared with control values without caffeine; ##p < 0.01, ###p < 0.001, compared with values without caffeine within 3-, 12-, and 24-month-old animals (two-way ANOVA with Bonferroni multicomparison test)