Dietary pattern changes, obesity and excess body fat in adults of a Brazilian birth cohort

Abstract Background Few studies have assessed dietary patterns (DPs) and the changes in these patterns over time in adults. The present study aimed to investigate whether possible changes in DPs in two assessments are associated with obesity and excess body fat. Methods A prospective study was conducted in which data were collected from 1082 adults of a Brazilian birth cohort during two periods 15 years apart (T1: 2002–2004; T2: 2016–2017). Food consumption was assessed in both periods using validated food frequency questionnaires. Three similar DPs were found in the two assessments, and adherence to these patterns was classified as prudent, risk or mixed. Nine DPs changes were defined. At T2, subjects with a body mass index ≥ 30.0 kg m – ² were classified as obese, and men and women with a body fat (BF) percentage ≥ 25.0 and ≥ 35.0, respectively, were classified as having excess BF. A directed acyclic graph was built to adjust the association for confounding variables. Results At T2, 34.4% of the subjects were obese and 61.4% had excess BF. In the adjusted analysis, the changes associated with obesity and excess BF were prudent–mixed (prevalence ratio [PR] 1.55; 95% confidence interval [CI] = 1.04–2.29 and PR = 1.35; 95% CI = 1.10–1.65), risk–risk (PR = 1.49; 95% CI = 1.03–2.13 and PR = 1.27; 95% CI = 1.04–1.53), risk–mixed (PR = 1.56; 95% CI = 1.05–2.31 and PR = 1.33; 95% CI = 1.07–1.63) and mixed–risk (PR = 1.61; 95% CI = 1.10–2.35 and PR = 1.29; 95% CI = 1.04–1.58). Conclusions A decline in food quality over time or stagnation in an unhealthy DP can lead to obesity and excess BF.