Association between Maternal Fish Consumption and Gestational Weight Gain: Influence of Molecular Genetic Predisposition to Obesity.

Sofus C Larsen,Ellen A Nohr,Marianne U Jakobsen,Camilla S Morgen,Lavinia Paternoster,Thorkild I A Sørensen,Lars Ängquist,Sjurdur F Olsen,George Davey Smith,Charles Laurin

doi:10.1371/journal.pone.0150105

Abstract

BackgroundStudies suggest that fish consumption can restrict weight gain. However, little is known about how fish consumption affects gestational weight gain (GWG), and whether this relationship depends on genetic makeup.ObjectiveTo examine the association between fish consumption and GWG, and whether this relationship is dependent on molecular genetic predisposition to obesity.DesignA nested case-cohort study based on the Danish National Birth Cohort (DNBC) sampling the most obese women (n = 990) and a random sample of the remaining participants (n = 1,128). Replication of statistically significant findings was attempted in the Avon Longitudinal Study of Parents and Children (ALSPAC) (n = 4,841). We included 32 body mass index (BMI) associated single nucleotide polymorphisms (SNPs) and 5 SNPs found associated with GWG. BMI associated SNPs were combined in a genetic risk score (GRS). Associations between consumption of fish, GRS or individual variants and GWG were analysed, and interactions between fish and the GRS or individual variants were examined.ResultsIn the DNBC, each portion/week (150 g) of fatty fish was associated with a higher GWG of 0.58 kg (95% CI: 0.16, 0.99, P<0.01). For total fish and lean fish, similar patterns were observed, but these associations were not statistically significant. We found no association between GRS and GWG, and no interactions between GRS and dietary fish on GWG. However, we found an interaction between the PPARG Pro12Ala variant and dietary fish. Each additional Pro12Ala G-allele was associated with a GWG of -0.83 kg (95% CI: -1.29, -0.37, P<0.01) per portion/week of dietary fish, with the same pattern for both lean and fatty fish. In ALSPAC, we were unable to replicate these findings.ConclusionWe found no consistent evidence of association between fish consumption and GWG, and our results indicate that the association between dietary fish and GWG has little or no dependency on GRS or individual SNPs.

Highlights

Many women gain excess weight during pregnancy, increasing the risk of complications during pregnancy and delivery, and in the longer term increasing the risk of both the mother and child of becoming overweight [1].A woman’s dietary intake is a seemingly obvious prerequisite for excess gestational weight gain (GWG)
In the Danish National Birth Cohort (DNBC), each portion/week (150 g) of fatty fish was associated with a higher GWG of 0.58 kg
We found no association between genetic risk score (GRS) and GWG, and no interactions between GRS and dietary fish on GWG

Summary

Introduction

A woman’s dietary intake is a seemingly obvious prerequisite for excess gestational weight gain (GWG). Studies of diet among pregnant women are sparse, but results from a randomized controlled trial of 324 men and non-pregnant women suggest that increasing fish intake in an energy-restrictive diet can promote weight loss [3]. Results from the few published studies investigating the relationship between intake of fish and GWG have been inconsistent. Studies suggest that fish consumption can restrict weight gain. Little is known about how fish consumption affects gestational weight gain (GWG), and whether this relationship depends on genetic makeup

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Results

Conclusion