Changes in liking for sweet and fatty foods following weight loss in women are related to prop phenotype but not to diet

Abstract

Objective: Changes in perceived intensity and liking of tasted foods have not been studied during weight loss from dieting. These outcomes were examined during a 6-month lifestyle intervention in women who had been classified by sensitivity to the bitter taste marker, 6-n-propylthiouracil (PROP), and then randomized to a low-fat or low-carbohydrate diet. Methods: Sixty-nine women (BMI 5 34.4 kg/m 2 ; age 5 44.2 years) followed the low-fat diet (n 5 31) or low-carbohydrate diet (n 5 38). At baseline and at 3, and 6 months, they rated overall liking and intensity of attributes in strawberry milk and salad dressing varying in sucrose (0%, 15%, and 30% wt/vol) or fat (10%, 30%, 50% wt/vol) content, respectively. Results: Perceived intensity of the attributes did not change. For all participants, the 15% and 30% sucrose milk samples were equally liked at baseline and 3 months, but by 6 months, the 15% sucrose sample was highest liked (P < 0.007). Also, the 50% fat sample was most liked at baseline and least liked by 6 months (P 5 0.04), and this effect was most pronounced in the nontasters (P < 0.02). There were no effects of diet prescription on liking. Conclusions: Weight loss from dieting resulted in a hedonic shift for foods with lower sucrose and fat content.

Determinants of Sweetness Preference: A Scoping Review of Human Studies

“…In two studies, it was reported that sweetness preference was not affected by weight loss, neither in obese children, obese adolescents [82], or obese adults [83], following a 12and 6-month weight loss intervention, respectively. In contrast, in the study by Burgess et al [84], obese females reported a significantly greater preference for only the strawberry milk sweetened with 15% sucrose following a 6-month weight loss program, whereas before the weight loss program there was a significant preference for strawberry milk sweetened with 15% or 30% sucrose over 0% sucrose. The latter findings suggest that the weight loss intervention among these obese females reduced their sweetness preference for the 30% sucrose solution.…”

“…In five experimental studies, the effects of weight loss on sweet preference were assessed (Table S3-6 of Supplementary File S3). In three of these studies, sweetness preference was assessed both before and after weight loss [82][83][84]. In two studies, it was reported that sweetness preference was not affected by weight loss, neither in obese children, obese adolescents [82], or obese adults [83], following a 12and 6-month weight loss intervention, respectively.…”

Factors Influencing the Phenotypic Characterization of the Oral Marker, PROP

“…This conclusion may be based, in part, on data showing that at high NaCl concentrations (>0.35 M), NaCl ratings are not independent of PROP taster status and diverge in super tasters [ 41 ]. Nevertheless, the use of NaCl as a reference standard has been successfully employed by numerous laboratories across the globe [ 17 , 18 , 27 , 33 , 34 , 38 , 39 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 ]. Data described later in this review illustrate this point.…”

“…The 1-solution and paper disk methods rely on empirically-derived cutoff scores for PROP taster classification. These techniques have been used in numerous investigations in our work [ 17 , 18 , 27 , 33 , 38 , 39 , 43 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 ] and the work of others [ 58 , 59 , 60 , 61 ]. PROP classifications obtained with this suite of methods is highly correlated with all known TAS2R38 genotypes [ 27 , 33 , 64 , 65 , 66 , 67 ] and differences in physiological responses such as prefrontal cortex activity [ 68 ] and degree of activation of peripheral taste function [ 69 , 70 ].…”

“…It has become our practice in recent years to define taster status primarily on the basis of PROP cutoff scores unless a participant gives a ‘borderline’ rating to PROP [ 18 , 39 , 52 , 54 , 55 , 56 ]. Only in rare instances (~4–6% of the time) is the NaCl rating needed to clarify an individual’s PROP classification.…”