Abstract
BACKGROUND: Diet is an important determinant of body weight and may modulate genetic susceptibility to obesity. OBJECTIVE: This systematic review and meta-analysis aimed to synthesize evidence related to interactions between polygenic risk and nutrient intakes on obesity outcomes. METHODS: MEDLINE, EMBASE, Web of Science, and Cochrane Library were systematically searched to identify observational studies that assessed interactions between polygenic risk and nutrient intakes on obesity-related outcomes. Random effects meta-analyses were performed for pooled polygenic risk score (PRS)-total fat intake and PRS-protein intake interaction coefficients on body mass index (BMI). RESULTS: Twenty-six publications were retrieved with studies conducted among European, Asian, and African samples. Dietary fats (saturated fat, omega-3, and trans fat) and energy intake were most frequently reported to interact with PRS on obesity outcomes, but the total number of studies available was low. No significant interactions were identified in meta-analyses of PRS interactions with total fat intake and protein intake on BMI. Several studies were rated as low quality, heterogeneity was high, and although study samples were racially diverse, PRSs tended to be based on samples of European ancestry. CONCLUSION: Evidence of interactions between polygenic risk and nutrient intakes on obesity outcomes is limited and inconsistent. Further research addressing limitations related to study quality and polygenic risk characterization is needed.