Key result
Physical activity is linked to lower fasting glucose, while weekly fast food predicts ~14% higher HOMA-IR.
Why the study?
It was unknown whether associations of physical activity and dietary habits in early adolescence with glycemic traits 5 years later are modified by type 2 diabetes polygenic risk scores.
Does higher physical activity or specific dietary habits improve glycemic markers in adolescents, and is this effect modified by genetic risk for type 2 diabetes?
Cohort (n=516)
No
Does higher physical activity or specific dietary habits improve glycemic markers in adolescents, and is this effect modified by genetic risk for type 2 diabetes?
Effect estimate: 14.20% higher (95% CI 0.05-28.35)
Higher physical activity in early adolescence is associated with more favorable glycemic markers 5 years later, with the greatest benefit seen in youth at higher genetic risk for type 2 diabetes.
Supports activity promotion and fast-food limits in at-risk youth; extends adult PRS data to adolescents but leaves causality open.
Introduction and Objective: We examined whether associations of physical activity and dietary habits in early adolescence with glycemic traits 5 years later were modified by type 2 diabetes (T2D) polygenic risk scores (PRS). Methods: We calculated a PRS for T2D, derived from the most recent adult T2D genome-wide association study, in a cohort of white non-Hispanic youth from Project Viva (MA, USA). At a median age 13y we assessed moderate-to-vigorous physical activity (MVPA, min/d) by accelerometry, and sugary drink, fast-food, and fruit and vegetable intakes by diet screener. At follow-up (median age 18y), we measured fasting glucose, insulin, and HbA1c. We estimated exposure by PRS interaction terms with linear regression models, adjusting for baseline age, sex, the first 3 genetic principal components, and socioeconomic factors. Results: In 516 youth (50% female), higher MVPA was associated with lower HOMA-IR and fasting glucose, with stronger associations among those at higher T2D-PRS (Figure). Consuming fast-food at least (vs. <) 1x/week was associated with 14.20% (95% CI: 0.05, 28.35) higher HOMA-IR, without evidence of interaction by T2D-PRS. We did not detect interactions between other dietary habits and T2D-PRS on glycemic markers. Conclusion: Youth at higher genetic risk for T2D may benefit more from increasing MVPA for T2D prevention, while limiting fast-food could be favourable irrespective of genetics. Disclosure S. Harnois-Leblanc: None. I. Aris: None. S. Rifas-Shiman: None. E. Oken: None. D. Manousaki: Research Support; Current; Sanofi. Speaker's Bureau; Current; Sanofi. Advisory Panel; Current; Sanofi. W. Perng: None. J. Merino: None. M. Hivert: None. Funding American Diabetes Association (7-23-PDFT2DY-03), National Institutes of Health (R01034568, R24ES030894)
No takes yet. Share an insight, caveat, or question.
Harnois‐Leblanc et al. (2026) conducted a cohort in Type 2 diabetes risk (n=516). Moderate-to-vigorous physical activity and fast-food intake vs. Lower physical activity and fast-food intake <1x/week was evaluated on HOMA-IR and fasting glucose at 5-year follow-up (14.20% higher, 95% CI 0.05-28.35). Higher physical activity lowered HOMA-IR and fasting glucose, especially with high genetic risk, while consuming fast-food ≥1x/week increased HOMA-IR by 14.20% (95% CI 0.05-28.35).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: