Figure 3.

Early-adolescent (WD-EA) vs. late-adolescent (WD-LA) consumption of a cafeteria-style Western diet (WD) increases energy intake during the WD diet period in male and female rats. (A) Energy consumption over time in male rats, with periods of exposure to the WD diet indicated within the dotted vertical lines (two-way ANOVA with diet, time [as repeated measure], and a diet × time interaction as factors; for diet, P=0.6394; for time, P<0.0001; for diet × time interaction, P<0.0001 – post hoc differences listed in Supplementary Table S1). (B) Percentage of kcal consumed from the WD diet components and percentage of kcal consumed per macronutrient for male WD-EA and WD-LA groups (unpaired t-test for all except the % kcal from peanut butter cups comparison, for which a Mann Whitney test was used; % kcal from HFHSD: P=0.5030, % kcal from potato chips: P=0.8058, % kcal from peanut butter cups: P=0.9323, % kcal from HFCS beverage: P=0.1358, % kcal from fat: P=0.2983, % kcal from carbohydrate: P=0.0995, % kcal from protein: P=0.3855). (C) Energy consumption over time in female rats, with periods of exposure to the WD diet indicated within the dotted vertical lines (Mixed effects model with factors of diet [fixed], time [fixed, as repeated measure], diet × time interaction [fixed], subject [random]; for diet, P=0.3247; for time, P<0.0001; for diet × time interaction, P<0.0001 – post hoc differences listed in Supplementary Table S1). (D) Percentage of kcal consumed from the WD diet components and percentage of kcal consumed per macronutrient for female WD-EA and WD-LA groups (unpaired t-test for all except the % kcal from carbohydrate comparison, for which Welch’s test for unequal variances was used; % kcal from HFHSD: P=0.0068, % kcal from potato chips: P=0.2869, % kcal from peanut butter cups: P=0.1188, % kcal from HFCS beverage: P=0.0055, % kcal from fat: P=0.2212, % kcal from carbohydrate: P=0.0018, % kcal from protein: P=0.0037). Error bars represent ± standard error of the mean; n=11–13/group; *P<0.05, ^a P<0.01 % kcal from HFCS comparison between female WD-EA and female WD-LA, ^z P<0.01 % kcal from HFHSD comparison between female WD-EA and female WD-LA † P<0.01 % kcal from carbohydrate comparison between female WD-EA and female WD-LA, ‡ P<0.01 % kcal from protein comparison between female WD-EA and female WD-LA. ANOVA, analysis of variance; HFCS, high-fructose corn syrup; HFHSD, high-fat high-sugar diet; WD, cafeteria diet; WD-EA, early-adolescent WD diet exposure; WD-LA, late-adolescent WD diet exposure; kcal, kilocalories; PN, postnatal day.