Changes in diet quality across life transitions from adolescence to early adulthood: a latent growth analysis

Background: Adolescence to early adulthood is a period of multiple life transitions. These transitions, along with changing resources and contexts, could contribute to significant changes in diet, which may persist into later adulthood. Objectives: We investigated diet quality trajectories from age 15 to 31 y and changes in diet quality associated with life transitions by sex. Methods: Data from the Project EAT (Eating and Activity in Teens and Young Adults) study in Minnesota, the United States were used to examine diet quality among a longitudinal cohort (n = 2524) across 4 waves (mean ages of 15, 19, 25, and 31 y). Average within-person changes in DASH (Dietary Approaches to Stop Hypertension) scores were analyzed using sex-specific latent growth models, incorporating underlying growth trajectories, 5 life transitions, and baseline sociodemographic and health characteristics. Results: Both sexes followed a quadratic trajectory of DASH scores, showing decreases in diet quality from Wave 1 to 2 followed by increases until Wave 4. However, males had increasingly worse diet quality than females. Compared with no such transition, leaving the parental home between Waves 1 and 2, was associated with transient decreases in diet quality at Wave 2 only for males (β: −2.34; 95% confidence interval [CI]: −3.57, −1.11). For females, cohabitating with a partner and becoming a parent between Waves 3 and 4 were related to decreases (β: −1.96; 95% CI: −3.45, −0.47) and increases (β: 1.85; 95% CI: 0.47, 3.23), respectively, in diet quality at Wave 4. Leaving full-time education and starting full-time employment showed negative and positive associations, respectively, with long-term diet quality for both sexes. Conclusions: Diet quality remained suboptimal throughout adolescence and improved across early adulthood. Targeted dietary interventions are welcome for young people who leave their parental home early or do not enter a structured school or workplace environment and for addressing sex differences in diet quality associated with family-related life transitions.