Summary: Picky eating in young children is not always a matter of willful behavior — genetics may play a role. Researchers have identified two taste-related genes linked to picky eating in preschoolers.
Source: ACES/University of Illinois.
Picky eating is common among preschool-age children and is often part of normal development. For some children, however, strong food preferences or persistent refusal to try new foods can contribute to nutritional problems, weight concerns, gastrointestinal issues, or the risk of later eating disorders.
Nutrition and family studies teams at the University of Illinois have spent the past decade investigating the features of picky eating and the factors that contribute to it. Their work has tracked typical feeding behaviors, parenting approaches, and how children respond in different settings. In a recent study, the researchers explored whether genetic variation in chemosensory (taste-related) genes is associated with picky eating behaviors in preschoolers.
“For most children, picky eating is a normal part of development,” says Natasha Cole, a doctoral student in the Division of Nutritional Sciences at the University of Illinois and the study’s lead author. “But for some children, the behavior becomes more concerning.” Cole, who is also involved in the Illinois Transdisciplinary Obesity Prevention Program, says the goal of this line of research is to identify biological and environmental determinants of picky eating early in life.
Earlier phases of the research identified common characteristics and patterns of picky eating among 2- to 4-year-olds and grouped children into distinct types based on behaviors such as limited food variety, frequent refusals, and strong mealtime control struggles. The team has also examined how caregiving style and childcare environments influence whether a child displays picky eating at home or in group care settings.
“Our research evolved from focusing only on the child to examining interactions among the child, caregivers, and the environment,” explains Soo-Yeun Lee, professor in the Department of Food Science and Human Nutrition at the University of Illinois. “We began to see that both the child’s individual traits and the environment shape feeding behaviors.”
To investigate genetic contributions, the researchers collected caregiver-reported information on breastfeeding history and eating behaviors for 153 preschoolers, along with saliva samples for DNA analysis. They examined variation in single nucleotide polymorphisms (SNPs) within five candidate genes linked to chemosensory perception.
Of the genes studied, two showed significant associations with picky eating patterns. Variation in TAS2R38 — a gene previously implicated in sensitivity to bitter tastes — was associated with reduced dietary variety. A second gene, CA6, which is also related to taste perception, was associated with greater struggles for control during mealtimes. Both genes have connections to bitter taste sensitivity, suggesting that children who are genetically more sensitive to bitter flavors may be more likely to reject certain vegetables and other foods with pronounced bitter notes.
In addition to taste, the researchers note that other sensory qualities such as smell, color, and texture can influence a child’s willingness to try or accept foods. The study’s authors recommend further research to determine how visual and olfactory cues interact with genetic taste sensitivity to shape food preferences in early childhood.
Cole emphasizes that early eating habits begin to form well before age two, yet most picky eating research focuses on toddlers and older preschoolers. In a companion review, the team examined the literature on picky eating in children younger than two years and considered factors across multiple ecological levels — from the child’s biological and sensory characteristics to family and caregiving environments.
“By two years of age, many children already have established eating habits,” Cole notes. “There is a notable gap in research on the transition from a milk-based diet to family foods, and that transition may be a key period for identifying how picky eating emerges.” The review found that caregiver perceptions of fussiness can increase across months during infancy and toddlerhood, suggesting that food-related fussy behavior can develop rapidly in early life.
Margarita Teran-Garcia, co-author and assistant professor with appointments in nutritional sciences, human development and family studies, and the Carle Illinois College of Medicine, highlights the importance of integrating data “from cell to society.” She explains that combining genetic, behavioral, and environmental information is essential to untangling how nature and nurture interact to shape eating behavior.
Funding: Funding was provided by the NIH/National Institute of Food and Agriculture, the U.S. Department of Agriculture, the Illinois Council for Agriculture Research, and the University of Illinois Health and Wellness Initiative.
Source: Stephanie Henry – ACES/University of Illinois
Image Source: NeuroscienceNews.com image is credited to ACES/University of Illinois.
Original Research: Abstract for “Variants in Chemosensory Genes Are Associated with Picky Eating Behavior in Preschool-Age Children” by Cole N.C., Wang A.A., Donovan S.M., Lee S.-Y., Teran-Garcia M., and the STRONG Kids Team in Journal of Nutrigenetics and Nutrigenomics. Published online October 2017, doi:10.1159/000478857
ACES/University of Illinois, “Got a Picky Eater? How ‘Nature and Nurture’ May Be Influencing Eating Behavior in Young Children.” NeuroscienceNews. October 3, 2017.
Abstract
Variants in Chemosensory Genes Are Associated with Picky Eating Behavior in Preschool-Age Children
Background/Aims: Picky eating is common among preschoolers and is linked to both underweight and overweight risk. While taste perception differs across individuals and can be influenced by genetic variation, it remained unclear whether specific chemosensory gene variants are associated with picky eating behavior. This study investigated associations between six single nucleotide polymorphisms (SNPs) across five candidate chemosensory genes and picky eating behaviors and adiposity in a preschool cohort.
Methods: Parents of 2- to 5-year-old non-Hispanic white preschoolers (n = 153) completed surveys on demographics, breastfeeding history, and child picky eating behaviors. Children’s height and weight were measured to calculate BMI z-scores, and saliva samples were collected for genotyping. Generalized linear models examined associations between genetic variation and picky eating behaviors and BMI z-scores, controlling for child age, sex, breastfeeding status, and parent education.
Results: After adjusting for covariates, SNPs in TAS2R38 (rs713598) and CA6 (rs2274327) were associated with picky eating behaviors. No SNPs were associated with BMI z-scores in this sample.
Conclusion: Genetic variants related to chemosensory perception may contribute to picky eating behavior in preschool-age children. Understanding these biological contributions alongside caregiving and environmental factors may help shape better strategies for supporting healthy eating habits in early childhood.
“Variants in Chemosensory Genes Are Associated with Picky Eating Behavior in Preschool-Age Children” by Cole N.C., Wang A.A., Donovan S.M., Lee S.-Y., Teran-Garcia M., and the STRONG Kids Team. Journal of Nutrigenetics and Nutrigenomics. Published online October 2017. doi:10.1159/000478857