Association Between Ultraprocessed Dietary Pattern and Weight Gain in Adults: The Nutrinet-Brasil Cohort Study

Ultraprocessed dietary patterns have been associated with higher risk of weight gain. Previous studies were conducted in high-income countries using dietary assessment tools not specifically designed to identify ultraprocessed foods. The purpose of this study was to examine the prospective association between ultraprocessed dietary pattern and risk of weight gain in Brazilian adults.

Data from 24,453 participants from NutriNet-Brasil cohort study who responded to 2 Nova24h dietary recalls at baseline and were followed for a median of 43.6 months were analyzed. Ultraprocessed dietary pattern was assessed on the basis of the contribution of ultraprocessed foods to total energy intake. Weight gain was defined as ≥5% and ≥10% increase from baseline body weight on the basis of self-reported measurements. Cox proportional hazards models, and stratified analyses were performed.

A linear dose-response association was observed: for each 10% increase in ultraprocessed foods contribution, the risk of ≥5% weight gain increased by 5% (10,092 cases, hazard ratio=1.05; 95% CI=1.04, 1.07), and the risk of ≥10% weight gain increased by 8% (4,865 cases, hazard ratio=1.08; 95% CI=1.06, 1.10). Compared with participants in the lowest quintile (<11.8% of ultraprocessed foods), those in the highest quintile (≥34.0%) had higher risk of weight gain (≥5%: hazard ratio=1.23; 95% CI=1.15, 1.31; ≥10%: hazard ratio=1.35; 95% CI=1.23, 1.48). These associations persisted but attenuated after adjustment for diet nutritional profile.

Higher exposure to ultraprocessed dietary pattern was associated with an increased risk of weight gain in Brazilian adults.