propylthiouracil and Hyperphagia

Taste blindness to the bitterness of PROP (6-n-propylthiouracil) has been used as a genetic marker for food selection and adiposity. We have shown that PROP non-taster (NT) women have higher BMIs and habitually consume more fat and energy than either medium-taster (MT) or super-taster (ST) women. These data imply that differences in dietary selection underlie the body weight differences among PROP taster groups. However, no studies investigated energy compensation in women classified by PROP status. We investigated if NTs would compensate less accurately for the calories and fat in a high-fat soup preload in a subsequent test meal compared to MTs and STs. Energy intake from a buffet meal was measured in 75 healthy non-diet-restrained, lean women 30 min after the ingestion of a high-fat soup preload (0.8 kcal/g; 55% calories from fat), calculated to represent 10% of resting energy expenditure for each subject, or the same volume of water. Subjects (n = 20-28/taster group) ate a standard breakfast followed 3 hr later by an ad-libitum buffet lunch, on two occasions. There were no differences in energy intake or macronutrient selection across taster groups after water. After soup, NTs consumed more energy than STs. Fat intake (as %-energy) was higher in NTs (46.4% ± 2.4) compared to either MTs (36.1 ± 1.9%) or STs (38.1% ± 2.3; p < 0.05). NTs overate by 11% ± 5 after the soup compared to MTs and STs who underrate by 16% ± 6 and 26% ± 10, respectively (p < 0.01). These data suggest that small discrepancies in short-term energy compensation and selection of fat after a mixed-nutrient, high-fat preload may play a role in positive energy balance and increased adiposity in women with the PROP non-taster phenotype.

Topics: Adiposity; Adult; Diet; Dietary Fats; Eating; Energy Intake; Feeding Behavior; Female; Food Preferences; Humans; Hyperphagia; Meals; Obesity; Propylthiouracil; Taste; Taste Perception; Water; Young Adult

Taste blindness to 6-n-propylthiouracil (PROP) is a common phenotype that has been associated with increased adiposity in women, and might be linked to increased selection of dietary fats. Since exposure to a variety of high-fat/energy-dense foods is known to promote excess energy intake, we investigated if PROP non-taster women would consume more fat and/or energy in a buffet setting than super-taster women. Subjects were non-diet restrained, lean, young women; 14 were non-tasters and 18 were super-tasters. Subjects ate lunch in the laboratory on four separate days. On one day they consumed an ad libitum, fixed-item lunch (control). On the other three days they consumed different buffet lunches (pizza/tacos/sub sandwiches with salad bar and choice of beverage and dessert). Energy intake from the control lunch did not differ between groups. When intake was averaged across the buffet lunches, non-taster women consumed 357+64 kcal more energy than during the control lunch (88% more), whereas super-taster women consumed 198+71 kcal more energy than during the control lunch (38% more). Neither fat intake nor selection of high-fat foods differed between groups. These data suggest that non-taster women consume more energy from a buffet meal than super-taster women, but not more fat. Increased responsiveness to a variety of energy-dense foods could be one mechanism contributing to increased energy intake and greater adiposity in non-taster women.

Topics: Adult; Dietary Fats; Energy Intake; Female; Humans; Hyperphagia; Propylthiouracil; Taste; Young Adult

Exposure to a variety of energy-dense foods promotes increased energy intake and adiposity. Taste blindness to the bitterness of 6-n-propylthiouracil (PROP) has been associated with increased adiposity in women and might be linked to an increased energy intake and greater selection of dietary fat.. We investigated whether PROP nontaster (NT) women would consume more fat and energy in a buffet setting than medium taster (MT) or supertaster (ST) women.. Seventy-five non-diet-restrained, lean, young women [mean ± SEM BMI (in kg/m²): 21.5 ± 0.6; age: 26.1 ± 1.3 y) ate lunch and dinner in the laboratory for 3 consecutive days under the following 2 conditions: ad libitum control meals (CONTs) or high-variety buffet meals (BUFFs). A standard breakfast was consumed each day of the study (4 - d washout between conditions).. NTs and MTs consumed more energy and fat (as the percentage of energy) from BUFFs than did STs (P < 0.01), which contributed to higher daily energy intakes in these 2 groups of women during BUFFs (2149 ± 49 kcal/d for NTs and 2209 ± 48 kcal/d for MTs compared with 1933 ± 50 kcal/d for STs; P < 0.01). Together, NTs and MTs consumed an extra 246 kcal/d during BUFFs than during CONTs. In addition, compared with STs, NTs and MTs consumed more added fats and sweets (servings/d; P < 0.003) and more energy from snacks (P < 0.01) across all study days.. NT and MT women consume more daily energy than do ST women when eating in a buffet setting, which is a common type of dietary exposure. This increase in energy intake over time could contribute to a positive energy balance and increased adiposity previously reported in these women.

Topics: Adult; Antimetabolites; Choice Behavior; Cohort Studies; Dietary Fats; Energy Intake; Feeding Behavior; Female; Humans; Hyperphagia; Meals; New Jersey; Overweight; Propylthiouracil; Snacks; Taste Disorders; Taste Perception; Young Adult