The SUN Project is a dynamic, prospective, multipurpose cohort of Spanish university graduates with an overall retention rate of 90%. The study population encompassed 8569 Spanish university graduates (mean age: 37 y) who were initially free of overweight or obesity. Self-reported weight (previously validated) was collected at baseline and updated every 2 y during the follow-up period. Fructan consumption and GOS consumption were assessed with the use of a validated semiquantitative 136-item food-frequency questionnaire and were updated after 10 y. Time-dependent Cox proportional hazards models were used to estimate HRs and 95% CIs for incident overweight and to adjust for potential confounding factors.
During follow-up (median: 9 y), 1964 incident cases of overweight were identified. After potential confounders were adjusted for, risk of overweight was 15% lower in participants in the highest quartile of fructan consumption (¿2.3 g/d) (95% CI: 0.74, 0.97; P-trend = 0.019). Subjects in the highest quartile of GOS consumption (¿0.45 g/d) had 17% lower risk of overweight (95% CI: 0.74, 0.94; P-trend = 0.001).
Higher prebiotic consumption was associated with lower risk of overweight in a cohort of initially normal-weight, middle-aged adults. This potential protection has been previously scarcely assessed; therefore, additional longitudinal studies are needed to confirm our results.