Associations Between School Start Times and Adolescent Dietary Intake: Results From a National Study

Area of Science:

• Public Health
• Nutritional Science
• Adolescent Health

Background:

• Earlier school start times are linked to negative adolescent health outcomes.
• Research on school start times and adolescent diet is limited.
• This study investigates the relationship between school start times and dietary intake in US adolescents.

Purpose of the Study:

• To assess the association between school start times and dietary intake in a national sample of US adolescents.
• To determine if earlier school start times predict greater intake of energy-dense, nutrient-poor foods.
• To examine if earlier school start times predict less healthful food intake.

Main Methods:

• Utilized data from the National Cancer Institute's Family Life, Activity, Sun, Health, and Eating (FLASHE) study (n=1371).
• Employed weighted least-squares regressions to analyze school start time as a predictor of dietary intake.
• Controlled for demographic and socioeconomic factors in the analysis.

Main Results:

• Adolescents in schools with earlier start times consumed more energy-dense, nutrient-poor foods, primarily due to higher intake of sugar-sweetened beverages and added sugars.
• Earlier school start times were unexpectedly associated with greater overall fruit intake.
• Post hoc analyses revealed earlier start times predicted higher fruit cup intake, but not vegetable intake.

Conclusions:

• Earlier school start times are associated with less healthy dietary patterns in adolescents, characterized by increased consumption of sugar-sweetened beverages and energy-dense, nutrient-poor foods.
• The association between earlier school start times and increased fruit intake warrants further investigation.
• Future research should utilize longitudinal designs and more detailed dietary assessments to explore these associations.