Dietary intake of young twins: nature or nurture?

Laura Pimpin,Gina L Ambrosini,Clare H Llewellyn,Laura Johnson,Cornelia Hm Van Jaarsveld,Susan A Jebb,Jane Wardle

doi:10.3945/ajcn.113.065250

Abstract

Background: The early years in life are increasingly recognized as a critical period for the development of diet-related behavioral traits. However, discussions continue on the relative role of genes and the environment in determining dietary intake, particularly in young children for whom detailed dietary information is limited.Objectives: This study tested the hypothesis that diet in early childhood is primarily determined by the environment rather than by genes. A secondary aim was to characterize the early childhood diet.Design: A classic twin design used 3-d dietary data collected at age 21 mo from the Gemini cohort. From the full sample of 2402 families with twins, dietary diaries were available for 1216 twin pairs (384 monozygotic and 832 dizygotic pairs) after exclusions. Intakes of macronutrients, food, and beverages were estimated. Twin analyses quantified the contributions of genetic and environmental factors to population variation in intake.Results: At age 21 mo, children consumed small portions of a wide range of family foods. The shared environment was the predominant determinant, contributing between 66% (95% CI: 52%, 77%; milk-based desserts) and 97% (95% CI: 95%, 98%; juice) of the variation in intake. Genetic factors were estimated to account for between 4% (95% CI: 0%, 10%; savory snacks) and 18% (95% CI: 14%, 23%; bread) of dietary intake variation.Conclusion: Shared environmental influences are the predominant drivers of dietary intake in very young children, indicating the importance of factors such as the home food environment and parental behaviors.

Highlights

A large body of research has investigated the early life dietary risk factors for obesity and chronic diseases [1]
The main aim of this study was to quantify the contribution of genes and environment to the variation in energy, macronutrient, food, and beverage intakes in young children by using data from the Gemini twin birth cohort
The results from this analysis show that shared environmental influences are the primary determinants of dietary intake in 21mo-olds, with genetic effects explaining small, significant, additional variation in dietary intake

Summary

Introduction

A large body of research has investigated the early life dietary risk factors for obesity and chronic diseases [1]. At least one twin in97% of pairs in the sample consumed common family foods such as cereal products, dairy, bread, meat and fish, fruit, and vegetables on at least one occasion during data collection (Table 2), with a low consumption of commercial infant foods (7% of total daily energy in consumers) (Table 3).

Objectives

Results

Conclusion