Ultra-processed food and the risk of overweight and obesity: a systematic review and meta-analysis of observational studies

Background Production and consumption of industrially processed food and drink products have risen in parallel with the global increase in overweight and obesity and related chronic non-communicable diseases. The objective of this study was to analyze the relationship between household availability of processed and ultra-processed products and the prevalence of excess weight (overweight plus obesity) and obesity in Brazil. Methods The study was based on data from the 2008–2009 Household Budget Survey involving a probabilistic sample of 55,970 Brazilian households. The units of study were household aggregates (strata), geographically and socioeconomically homogeneous. Multiple linear regression models were used to assess the relationship between the availability of processed and ultra-processed products and the average of Body Mass Index (BMI) and the percentage of individuals with excess weight and obesity in the strata, controlling for potential confounders (socio-demographic characteristics, percentage of expenditure on eating out of home, and dietary energy other than that provided by processed and ultra-processed products). Predictive values for prevalence of excess weight and obesity were estimated according to quartiles of the household availability of dietary energy from processed and ultra-processed products. Results The mean contribution of processed and ultra-processed products to total dietary energy availability ranged from 15.4% (lower quartile) to 39.4% (upper quartile). Adjusted linear regression coefficients indicated that household availability of ultra-processed products was positively associated with both the average BMI and the prevalence of excess weight and obesity, whereas processed products were not associated with these outcomes. In addition, people in the upper quartile of household consumption of ultra-processed products, compared with those in the lower quartile, were 37% more likely to be obese. Conclusion Greater household availability of ultra-processed food products in Brazil is positively and independently associated with higher prevalence of excess weight and obesity in all age groups in this cross-sectional study.

Cardiovascular disease development is related to known risk factors (such as diet and blood lipids) that begin in childhood. Among dietary factors, the consumption of ultra-processing products has received attention. This study investigated whether children's consumption of processed and ultra-processing products at preschool age predicted an increase in lipid concentrations from preschool to school age.

To estimate the association between food intake and metabolic syndrome (MetS). Cross-sectional design conducted from July 2006 to December 2007. Adolescents assisted by the Family Doctor Program (FDP) in Niterói, a metropolitan area in Rio de Janeiro State, Brazil. Survey of 210 adolescents. Individuals with three or more of the following components of MetS were classified as having this syndrome: TAG ≥ 110 mg/dl; HDL cholesterol 100 mg/dl; and blood pressure ≥90th percentile. A semi-quantitative FFQ was used, and foods were grouped as: unprocessed or minimally processed foods (Group 1), processed culinary and food industry ingredients (Group 2) and ultra-processed foods (Group 3). The associations between food consumption and MetS were adjusted for sociodemographic, behavioural and family history covariates and were estimated using generalized estimation equations with the Poisson regression model. MetS was diagnosed in 6·7 % of the adolescents; the most frequent diagnostic criteria included the reduction of HDL cholesterol (46·7 %), elevated serum glucose (17·1 %) and the elevation of waist circumference (16·7 %). Crude analysis showed higher average daily intakes of energy, carbohydrates and ultra-processed foods among adolescents with MetS. After statistical adjustment, the intake of ultra-processed foods (≥3rd quartile) remained associated with MetS (prevalence ratio = 2·5; P = 0·012). High consumption of ultra-processed foods was associated with the prevalence of MetS in this adolescents group.