Extended Data Fig. 1: A Low BCAA diet promotes the metabolic health of aged wild-type mice.

a-g, Female and h-n, Male C57BL/6 J.Nia mice were fed the indicated diets beginning at 16 months of age. a, The lean mass of a subset of female mice was tracked (n varies by month; maximum N = 10 biologically independent animals for both groups; * p < 0.05 (p value by month of age: 19 mo. = 0.0091, 21.5 mo. <0.0001, 24.5 mo. = 0.0004). b, Food consumption over time calculated as total kcal/d (maximum N = 3 independent cages for both groups). c, Energy expenditure (Heat) was assessed using metabolic chambers at 20 months of age (N; Control = 20, Low BCAA = 17 biologically independent animals). d, Respiratory exchange ratio and e, ambulatory movement was assessed using metabolic chambers at 20 and 25 months of age (maximum N; Control = 20, Low BCAA = 17 biologically independent animals; * p < 0.05 (p value for d by month of age: 20 mo. light=0.0056, dark=0.0105, 25 mo. dark=0.0012). f, Area under the curve (AUC) corresponding to the glucose tolerance test in Fig. 2g as well as repeat tests performed at 19 and 24 months of age (maximum N = 20 biologically independent animals for both groups; * p < 0.05, # p < 0.1 (p value by month of age: 17 mo. = 0.0034, 19 mo. = 0.0714, 24 mo. = 0.0016). g, Insulin tolerance test and corresponding area under the curve after four weeks of diet feeding (N; Control = 20, Low BCAA = 15 biologically independent animals). h, The lean mass of a subset of male mice was tracked (n varies by month; maximum N = 20 biologically independent animals for both groups, * p = 0.0066). i, Food consumption over time calculated as total kcal/d (maximum N = 3 independent cages for both groups). j, Energy expenditure (Heat) was assessed using metabolic chambers at 25 months of age (N = 13 biologically independent animals for both groups). k, Respiratory exchange ratio and (l) ambulatory movement was assessed using metabolic chambers at 20 and 25 months of age (maximum N = 14 biologically independent animals for both groups). m, AUC corresponding to glucose tolerance test in Fig. 2m as well as repeat tests performed at 19 and 24 months of age (maximum N = 20 biologically independent animals for both groups; * p < 0.05 (p-value by month of age: 17 mo. = 0.0006, 19 mo. =0.0240, 24 mo. = 0.0026). n, Insulin tolerance test and corresponding area under the curve after four weeks of diet feeding (N; Control = 10, Low BCAA = 9 biologically independent animals; * p = 0.0192). a-b,d-f,h-i,k-m, Statistics for the overall effects of diet, age, and the interaction represent the p value from a mixed-effects model (restricted maximum likelihood [REML]) or two-way repeated measures ANOVA, multiple comparisons by two-sided Sidak’s post-test. c,j, Energy expenditure data was analysed by linear regression of energy expenditure by body weight (ANCOVA). g,n, AUC comparisons were made by two-sided t-test, * p < 0.05. Data are represented as mean ± SEM.