Impact of dietary and obesity genetic risk scores on weight gain

Background: Whether genetic background and/or dietary behaviors influence weight gain in middle-aged subjects is debated. Objective: To assess whether genetic background and/or dietary behaviors are associated with changes in obesity markers (BMI, weight, and waist and hip circumferences) in a Swiss population-based cohort. Methods: Cross-sectional and prospective (follow-up of 5.3 y) study. Two obesity genetic risk scores (GRS) based on 31 or 68 single nucleotide polymorphisms were used. Dietary intake was assessed using a semiquantitative FFQ. Three dietary patterns Meat & fries (unhealthy), Fruits & vegetables (healthy), and Fatty & sugary (unhealthy), and 3 dietary scores (2 Mediterranean and the Alternative Healthy Eating Index [AHEI]) were computed. Results: On cross-sectional analysis (N = 3033, 53.2% females, 58.4 10.6 y), obesity markers were positively associated with unhealthy dietary patterns and GRS, and negatively associated with healthy dietary scores and patterns. On prospective analysis (N = 2542, 54.7% females, age at baseline 58.0 +/- 10.4 y), the AHEI and the Fruits & vegetables pattern were negatively associated with waist circumference gain: multivariate-adjusted average +/- SE 0.96 +/- 0.25 compared with 0.11 +/- 0.26 cm (P for trend 0.044), and 1.14 +/- 0.26 compared with -0.05 +/- 0.26 cm (P for trend 0.042) for the first and fourth quartiles of the AHEI and the Fruits & vegetables pattern, respectively. Similar inverse associations were obtained for changes in waist >5 cm: multivariate-adjusted OR (95% CI): 0.65 (0.50, 0.85) and 0.67 (0.51, 0.89) for the fourth versus the first quartile of the AHEI and the Fruits & vegetables dietary pattern, respectively. No associations were found between GRS and changes in obesity markers, and no significant gene-diet interactions were found. Conclusion: Dietary intake, not GRS, are associated with waist circumference in middle-aged subjects living in Lausanne, Switzerland.

Automated summary

In a Swiss population-based cohort study, it was found that obesity markers were positively associated with unhealthy dietary patterns and genetic risk scores (GRS), and negatively associated with healthy dietary scores and patterns. However, only dietary intake, not genetic background, was found to be associated with waist circumference in middle-aged subjects living in Lausanne, Switzerland.