Interaction between familial history of obesity and fat intakes on obesity phenotypes

Aim: To evaluate whether familial history of obesity (FHO) interacts with dietary fat intake (DFI) on obesity-related phenotypes. Methods: We recruited 664 participants aged between 18 and 55 years. A positive FHO (FHO+) was defined as having at least 1 obese first-degree relative and a negative FHO (FHO-) as no obese first-degree relative. Dietary intakes were collected from a food-frequency questionnaire. Body mass index, weight and waist girth were recorded using standard procedures. Fat mass and fat-free mass were assessed by electrical bioimpedance. Results: Significant interaction effects (FHO x DFI) were observed for body mass index, weight, waist girth and fat mass (p interaction = 0.05, 0.04, 0.04, 0.02, respectively). Among FHO+ individuals, indices of obesity increased with an increasing amount of DFI, whereas these associations were not observed in FHO- individuals. We also found that FHO+ individuals consuming a high-fat diet were at higher risk of obesity than FHO- individuals consuming a low-fat diet (3.6, CI 2.1-6.2). Conclusion: These results suggest a stronger relationship between DFI and obesity-related phenotypes in individuals with FHO+.