Ability to Taste 6‐n‐Propylthiouracil and BMI in Low‐income Preschool‐aged Children

Abstract

Background: Sensitivity to the bitter compound 6-n-propylthiouracil (PROP) is genetically mediated. Sensitivity to PROP has been associated with weight status in both adults and children. Objective: To determine whether there is an association between PROP sensitivity and BMI in low-income children of diverse race/ethnicity, among whom there is a high prevalence of obesity. Methods and Procedures: Eighty-one preschool-aged children attending Head Start tasted a solution of 560 μmol/l PROP and reported whether it tasted "like water" or "like something else". Mothers reported child's race, age, maternal education, maternal weight and height, child's reluctance to sample new foods via the Food Neophobia Scale (FNS), and child's dietary intake using a food frequency questionnaire. Child weight and height were measured. BMI was calculated and for children, expressed in z-scores. Regression analyses were used to evaluate the relationship between child's PROP taster status and BMI z-score, testing covariates child's age, gender, race, maternal education and BMI, and child's FNS score. Children's dietary intake was compared by PROP taster status. Results: PROP tasters, compared with nontasters, had significantly higher BMI z-scores (0.99 (s.d. 1.24) vs. 0.03 (1.12), P = 0.004) and had a significantly higher prevalence of overweight (31.8% vs. 5.6%, P = 0.025), but demonstrated no differences in reported dietary intake. The most parsimonious model predicting the child's BMI z-score included only maternal BMI and the child's PROP taster status (R 2 = 22.3%). Discussion: A genetically mediated ability to taste bitter may contribute to obesity risk in low-income, preschool-aged children.

Relationship of intake of plant-based foods with 6-n-propylthiouracil sensitivity and food neophobia in Japanese preschool children

“…Both the studies assessed consumption of vegetables using food-frequency questionnaires in preschool children in the United States, but no significant association was found (Keller et al, 2002;Lumeng et al, 2008). These results were similar to those of our study.…”

“…Some studies have found that PROP tasters do not like vegetables, such as raw spinach (Turnbull and Matisoo-Smith, 2002) and broccoli (Keller et al, 2002;Bell and Tepper, 2006), and soy foods (Gayathri Devi et al, 1997). Two previous studies assessed the relationship of usual consumption of vegetables and fruits with PROP sensitivity in children, but neither study found significant associations between them (Keller et al, 2002;Lumeng et al, 2008). There has been no report on the relationship between PROP sensitivity and soy food intake in children.…”

Influences of weight, age, gender, genetics, diseases, and ethnicity on bitterness perception: a narrative review of current methodological aspects

“…On the other hand, Garcia-Burgos and Zamora [13] evaluated the relationship between the facial reaction to the food bitterness and body mass index (BMI) and reported evidence of high levels of facial expression for bitterness in patients with a high BMI (p = 0.07). Lumeng et al [17] detected a 6-point higher BMI percentile among taster subjects than among those unable to perceive bitterness (non-tasters) in a sample of lowincome volunteers (p = 0.0002). Several studies also suggest that children incapable of sensing PROP [15] No correlations between bitterness perception and anthropometric variables, energy consumption or hormone levels Nasser et al…”

“…2008 [17] Six-point higher BMI percentile among taster subjects than among those unable to perceive bitterness (non-tasters) in a sample of low income volunteers…”

Genetics of Taste and Smell

“…51-54 However, a direct relationship between TAS2R38 genotype, food intake, and body weight has not been detected in epidemiological studies 55,56 or in genome-wide studies of association with body mass index, a measure of obesity. 10,57,58 Thus, if alleles of this bitter receptor gene can directly affect food intake or body weight, they are too weak to be detected in the population as a group.…”