Myles Faith, PhD and colleagues at the University of Pennsylvania School of Medicine and the Children's Hospital of Philadelphia evaluated the eating patterns of more 792 twins aged 7 years old. The researchers found that genetics mostly dictates a child's picky palate and cravings for items like peanut butter and jelly. The findings support earlier animal experiments and adult twin studies that linked eating behaviors to genetics.
"To our knowledge, this is one of the largest investigation[s] to document genetic influences on the 24-[hour] food and beverage intake of prepubertal children, which suggests that genes may contribute considerably to ... children's eating patterns," the authors write in the April issue of the American Journal of Clinical Nutrition.
The study group included both identical and fraternal (non-identical) twins. The children's parents provided information regarding what each child ate and drank the previous day, including serving size. Researchers grouped foods into nine categories: bread and butter; peanut butter and jelly; breakfast cereal and milk; fruit; red meat and pork; vegetables; candy; fish and lemon; and high-salt snack foods.
Genetics seemed to influence boys' choice of food and beverages more often than in girls. Boys ate a lot more peanut butter and jelly sandwiches than girls, who showed no genetic preference for this type of meal. Identical twins, who have the exact same genes, seemed to choose more similar foods and beverages than non-identical twins.
Shared environmental factors, such as the number of snacks in the home, had a greater influence on the girls' food and beverage choices.
Understanding why a child rejects or embraces certain foods may help ease the frustrations of millions of parents who struggle every day to get their child to eat -- if only to assure them that it is not their fault. Such research may also help scientists determine if genetically dictated eating patterns play a role in childhood obesity.
Results from this study suggest that a child's body mass index was generally unrelated to their specific food consumption. But the study's researchers caution that further studies are needed to determine if genetically influenced eating habits result in calorie and nutrition changes that lead to obesity.