Diet quality and genetic association with body mass index: results from 3 observational studies.

Am J Clin Nutr
Authors
Keywords
Abstract

BACKGROUND: It is unknown whether dietary quality modifies genetic association with body mass index (BMI).

OBJECTIVE: This study examined whether dietary quality modifies genetic association with BMI.

DESIGN: We calculated 3 diet quality scores including the Alternative Healthy Eating Index 2010 (AHEI-2010), the Alternative Mediterranean Diet score (AMED), and the Dietary Approach to Stop Hypertension (DASH) diet score. We examined the interactions of a genetic risk score (GRS) based on 97 BMI-associated variants with the 3 diet quality scores on BMI in 30,904 participants from 3 large cohorts.

RESULTS: We found significant interactions between total GRS and all 3 diet scores on BMI assessed after 2-3 y, with an attenuated genetic effect observed in individuals with healthier diets (AHEI: P-interaction = 0.003; AMED: P = 0.001; DASH: P = 0.004). For example, the difference in BMI (kg/m2) per 10-unit increment of the GRS was smaller among participants in the highest tertile of AHEI score compared with those in the lowest tertile (0.84; 95% CI: 0.72, 0.96 compared with 1.14; 95% CI: 0.99, 1.29). Results were consistent across the 3 cohorts with no significant heterogeneity. The interactions with diet scores on BMI appeared more significant for central nervous system GRSs (P  0.05 for 3 diet scores).

CONCLUSIONS: A higher diet quality attenuated genetic predisposition to obesity. These findings underscore the importance of maintaining a healthful diet for the prevention of obesity, particularly for those individuals with a strong genetic predisposition to obesity. This trial was registered with the Clinical Trial Registry as NCT03577639.

Year of Publication
2018
Journal
Am J Clin Nutr
Volume
108
Issue
6
Pages
1291-1300
Date Published
2018 Dec 01
ISSN
1938-3207
DOI
10.1093/ajcn/nqy203
PubMed ID
30351367
PubMed Central ID
PMC6290366
Links
Grant list
UM1 CA167552 / CA / NCI NIH HHS / United States
R01 HL035464 / HL / NHLBI NIH HHS / United States
UM1 CA186107 / CA / NCI NIH HHS / United States
P01 CA087969 / CA / NCI NIH HHS / United States
R01 CA049449 / CA / NCI NIH HHS / United States
R01 HL034594 / HL / NHLBI NIH HHS / United States
R01 HL088521 / HL / NHLBI NIH HHS / United States
P30 DK046200 / DK / NIDDK NIH HHS / United States
U01 HG004399 / HG / NHGRI NIH HHS / United States
P30 DK046200 / DK / NIDDK NIH HHS / United States
U54 CA155626 / CA / NCI NIH HHS / United States
U01 HG004728 / HG / NHGRI NIH HHS / United States
K01 HL129892 / HL / NHLBI NIH HHS / United States