EVIDENCE FOR A GENETIC INFLUENCE ON PREFERENCE FOR SOME FOODS

Objective The purpose of this study was to evaluate genetic influence on preference for 17 foods. The relationship between preference and use of these foods was also examined. The study focused on frequently eaten foods and on foods consumed less frequently but promoted for good health. Design Food preferences were investigated in young monozygotic and same-sex dizygotic twin pairs living at home and sharing the same environment. Subjects provided preference ratings after tasting each food. A food frequency questionnaire was used to determine whether the genetic component of preference is associated with food use. Subjects Subjects were 14 pairs of monozygotic twins and 21 pairs of same-sex dizygotic twins, aged 9 to 18 years. They were recruited on a volunteer basis from public schools in Cincinnati, Ohio. Main outcome measures We found a greater similarity in food preference between members of monozygotic twin pairs than between dizygotic twin pairs, which suggests an important role for genetics in accounting for individual differences in food preference. Statistical analyses performed Food preference data were analyzed using Pearson correlation coefficients and Fischer z scores. Additional estimates of heritability were obtained by applying the Mann-Whitney nonparametric t test and the Holzinger index. Food use was correlated with preference using Pearson correlation coefficients. Results Significant differences in intrapair correlations for monozygotic and dizygotic twins R-ere found for orange juice (z=5.39; P<.05), broccoli (z=2.60; P<.05), cottage cheese (z=2.54; P<.05), chicken (z=2.54; P<.05), sweetened cereal (z=2.00; P<.05), and hamburger (z=1.95; P<.10). The generic component of preference was correlated with use for only two foods. Applications/conclusions It is important for nutritionists to realize that heritable factors may influence selection of a range of foods, including some that are promoted for good health. If health-promoting foods are to be included in the diet, accessibility and exposure to these foods must be increased.