OBJECTIVE

Our objective was to evaluate the association between ultra-processed food (UPF) consumption and body weight change after participating in nutritional intervention.

DESIGN

Our study was a 12-month follow-up of participants in a randomized controlled community trial.

SETTING

Brazilian Primary Health Care.

PARTICIPANTS

The participants were health promotion services users. Users in the control group (CG) performed the service's usual intervention, while those in the intervention group (IG) additionally participated for seven months in nutritional intervention. Socioeconomic data, self-health, perception of time spent in health promotion services, and weight loss attempts were investigated. Food consumption was obtained by 24 h food recall and categorizing these in quartiles according to the Nova system of food classification. Weight was measured and changes in the 12-month period were calculated by subtracting the weight at follow-up from the baseline measurement.

RESULTS

Of the participants, 88.1% were females aged 56.7 ± 11.8 with 19.7 ± 15.3 months of participation in the service. In the fourth quartile (highest UPF consumption), the % contribution of calories per consumption of UPFs was 47.7%, with no differences between the IG and CG ( = 0.406). Adjusted after 12 months, when comparing those with lower consumption of UPFs (first quartile), individuals from the second, third, and fourth quartiles had positive weight variation. Respectively, these variations were as follows: 0.363 kg (95% CI: 0.038; 0.689; = 0.029); 0.467 kg (95% CI: 0.159; 0.776; = 0.003); and 0.389 kg (95% CI: 0.061; 0.717; = 0.020, with no differences between IG and CG).

CONCLUSIONS

The percentage contribution of calories from UPFs was associated with positive weight change, which contributes to the growing evidence of the relationship between UPFs and obesity.