Abstract
Purpose
The prevalence of overweight/obesity among French Polynesian adolescents is alarming. This study aims to prevent rises in obesity by modifying school food and the physical environment of French Polynesian adolescents.

Methods
During the 5-month study, 240 adolescents from a Tubuai island college (in French Polynesia) received a balanced diet based almost exclusively on local agricultural products and fishing by the island community. They were divided into three subgroups according to their college attendance status: external (n = 14), half residents (n = 155), and residents (n = 71). To increase energy expenditure, weekly physical activity was augmented by 2–4 hours of training in Polynesian Va'a canoes. Anthropometric parameters were recorded, and blood samples collected at baseline and after 5 months. Collegians from Rurutu, a neighboring island, were considered as controls (N = 90).

Results
At baseline, overweight/obesity prevalence was 60% (with 28% obesity) in the intervention group. After 5 months, adjusted weight gain was ?.76 kg for residents (95% confidence interval [CI], ?1.59 to .08), 1.34 kg for half residents (95% CI, .84–1.83), 1.82 kg for externs (95% CI, .66–2.97), and 4.2 kg (95% CI, 3.4–5.0) in the controls. Our results indicate that the more adolescents were subjected to food and physical activity commitments, the higher was the rate among those who lost weight. We noted that the weight change magnitude predicted insulin, glucose, and visceral obesity modifications.


Conclusions

This 5-month school-based intervention slowed weight gain and improved the health of Polynesian collegians. The implementation of longer school-based interventions deserves evaluation.