This study, published in the Journal of American Nutrition, August 2007, was conducted by Dr. Lucy Cooke and colleagues from University College London. For this study, researchers surveyed the parents of 5390 pairs of identical and fraternal twins, ages 8 – 11 years old. The study of twins allowed researchers to separate environmental and genetic factors, as identical twins share 100% of their genes, and fraternal twins share only about half; however, twins share the same environmental factors.

“Food neophobia” is the reluctance to try new foods, and “this avoidance may have had an evolutionary advantage in preventing exposure to potentially toxic foods,” according to researchers.

Researchers determined that identical twins tend more toward food neophobia than fraternal twins, with inheritance attributed to about 78% of these inclinations. Shared environment seemed to have no effect, while 22% of the tendencies were attributed to non-shared environmental factors. Other past studies have also found behavioral similarities among family members to be attributed to genetics over environment.

Researchers also found that “new foods can become familiar, and disliked foods become liked, with repeated presentation, although the process might be more laborious with a highly neophobic child.”