Short-term vegetable intake by young children classified by 6- n-propylthoiuracil bitter-taste phenotype

Abstract

Genetic variation in sensitivity to the bitterness of 6-n-propylthiouracil (PROP) is thought to play a role in the acceptance and rejection of bitter-tasting vegetables by young children. We investigated the relation between the PROP bitter-taste phenotype and acceptance and consumption of vegetables by young children. We hypothesized that nontasters of PROP would give higher hedonic ratings to bitter-tasting vegetables and would consume more bitter vegetables than would tasters of PROP. Sixty-five preschool children were identified as tasters (n = 24) or nontasters (n = 41) of PROP. Children were allowed to select from among 5 types of vegetables (black olives, cucumbers, carrots, red pepper, and raw broccoli) to consume in a free-choice intake test and to give hedonic ratings to the vegetables. The nontaster children consumed more vegetables than did the taster children during the free-choice test (0.91 servings compared with 0.48 servings; P < 0.05). This difference reflected the higher consumption of the more bitter-tasting vegetables (olives, cucumber, and broccoli) by the nontaster children (P < 0.05). Only 8% of the nontaster children consumed no vegetables in the free-choice test compared with 32% of taster children (P < 0.03). The nontaster children also liked raw broccoli more than did the taster children in the hedonic test (P < 0.05). The nontaster children consumed more vegetables, particularly the vegetables that were bitter tasting, than did the taster children during a free-choice intake test. These novel findings suggest that the PROP bitter-taste phenotype contributes to the development of vegetable acceptance and consumption patterns during early childhood.