Fast food intake among adolescents: secular and longitudinal trends from 1999 to 2004.

Objectives: To examine secular and longitudinal changes (1999-2004) in fast food intake among adolescents.

Methods: Adolescents from Minnesota participating in Project EAT (n=2516) were surveyed in 1999 and 2004. Mixed-model regressions were used to assess secular and longitudinal changes in percentage reporting frequent fast food intake (> or =3 times/week) and weekly fast food intake.

Results: Between 1999 and 2004, a secular increase in the percent of adolescents of middle (high school-aged) adolescents reporting frequent fast food consumption was observed (females: 18.9% to 27.3%, p<.01, males: 23.6% to 30.2%, p=.06). Longitudinal increases in frequent fast food consumption were seen from early to middle adolescence (females: 15.8% to 27.3%, p<.01, males: 16.8% to 30.2%, p<.01), and among males, from middle to late adolescence (23.6% to 32.0%, p<.01).

Conclusions: The secular increase in fast food consumption among middle adolescents suggests that socio-environmental changes between 1999 and 2004 may have contributed to adolescents' fast food intake, while the longitudinal trends indicate the importance of developmental influences on fast food intake. The transition from early to middle adolescence, and for males, from middle into late adolescence, are key periods during which efforts to reduce fast food consumption are needed.