Consistent and changing consumption of fast-food and full-service meals and 3-year weight change in a large population cohort study

An average American consumes 3 meals weekly from fast-food or full-service restaurants, which contain more calories, fat, sodium, and cholesterol than meals prepared at home. This study examined whether consistent and changing fast-food or full-service consumption was associated with weight change over a 3-y period. Among 98,589 US adults from the American Cancer Society’s Cancer Prevention Study-3, self-reported weight and fast-food and full-service consumption from 2015 and 2018 were examined using a multivariable-adjusted linear regression analysis to assess the association of consistent and changing consumption on 3-y weight change. Individuals who made no changes to their fast-food or full-service intake over the study period gained weight regardless of consumption frequency, although low consumers gained less weight than high consumers (low fast-food: β = −1.08; 95% CI: −1.22, −0.93; low full-service: β = −0.35; 95% CI: −0.50, −0.21; P < 0.001). Decreased fast-food intake during the study period (e.g., from high [>1 meal/wk] to low [≤0.5 meal/wk], high to medium [>0.5 to ≤1 meal/wk], or medium to low) and decreased full-service intake from high (≥1 meal/wk) to low (