RESEARCH
Original Research
Relationship of 6-n-Propylthiouracil Taste Intensity and Chili Pepper Use with Body Mass Index, Energy Intake, and Fat Intake within an Ethnically Diverse Population Sung Eun Choi, PhD, RD; Jacqueline Chan, MS, RD ARTICLE INFORMATION Article history: Accepted 3 September 2014 Available online 20 November 2014
Keywords: 6-n-propylthiouracil Hot chili pepper Energy intake Fat intake Body mass index 2212-2672/Copyright ª 2015 by the Academy of Nutrition and Dietetics. http://dx.doi.org/10.1016/j.jand.2014.09.001
ABSTRACT Background One of the weight-loss strategies that has attracted attention is the use of spicy foods. It has been suggested that spicy food preference is related to a genetically predetermined sensitivity to the bitter compound 6-n-propylthiouracil (PROP). Objective Our aim was to examine the relationship of PROP taste intensity and hot chili pepper use with body mass index (BMI), energy intake, and fat intake. Design This study utilized a cross-sectional design. Participants/setting The sample included 350 subjects (154 male, 196 female) ages 18 to 55 years living in the New York City area. Main outcome measures BMI was calculated by measuring weight and height, and the sensitivity to PROP was evaluated using the PROP filter paper method. Subjects also rated the frequency of usage and preference for hot chili pepper using a chili pepper questionnaire. Their daily energy and fat intake were assessed using a food frequency questionnaire. Statistical analyses performed An independent sample t-test compared subject characteristics between groups based on sex, PROP status, and hot chili pepper user status for the continuous variables, and the c2 test was used for categorical variables. One-way analysis variance examined the differences in subject characteristics across four ethnicities. To predict BMI, energy intake, and fat intake, multiple linear regression models were fit with the covariates of age, sex, ethnicity, chili pepper score, and PROP mean. Results The values for BMI, energy intake, and fat intake of PROP tasters were significantly lower than those of PROP nontasters (P¼0.03, P135 food items all relating to the diet during the previous year in 10 categories: fruits and juices; vegetables and grains; meat, poultry, eggs and fish; mixed dishes; breads, salty snacks, spreads; breakfast cereals; sweets; dairy products; beverages; and foods to be added. The FFQ has been validated against 24-hour recall data.48,49 Upon completion of FFQ, registered dietitian nutritionists individually reviewed the FFQ and any discrepancies/questions were addressed. The daily intake per item was entered into the Food Processor software program (version 10.12, 2012, ESHA) to March 2015 Volume 115 Number 3
RESEARCH Please circle the appropriate answer to each question below. 1.
2.
3.
4. 5. 6.
How often do you eat all types of chili pepper in foods, including Mexican, Indian, Chinese, and other foods that contain chili pepper and cause tingling or burning? 1¼once a year or less 2¼less than once a month 3¼1-3 times per month 4¼Once a week 5¼3-4 times a week 6¼every day 7¼more than once a day How much do you like the taste of chili pepper in your food? 1 2 3 4 5 6 7 8 9 Dislike extremely Like extremely How much do you like the burn of chili pepper in your food? 1 2 3 4 5 6 7 8 9 Dislike extremely Like extremely I think chili pepper makes food taste better. True / False Without hot spices, I find that food tastes too bland. True / False I find it hard to appreciate the flavors of food when the food contains hot spices. True / False Thank you!
Figure. Chili pepper questionnaire used when categorizing chili pepper users and nonusers and evaluating chili pepper use and liking for adult subjects. Figure created using text from reference 16, by permission of Oxford University Press. analyze the daily energy intake and fat intake for each subject.
Chili Pepper Questionnaire The chili pepper questionnaire items16 developed by Lawless and colleagues (see Figure) were used to categorize chili pepper users and nonusers and to calculate a composite score of chili pepper use and liking (chili pepper score) in this study. On question 1 of the questionnaire, the subjects with responses of 1, 2, or 3 were categorized as chili pepper nonusers, and the subjects with responses of 5, 6, or 7 were categorized as chili pepper users. Subjects with the middle response of 4 (ie, once a week) were not included in the study to make the characteristics more distinct between the two categories.16 The chili pepper score was calculated by combining the responses from the six questions in the same way that was used in the study conducted by Lawless and colleagues.16
Anthropometric Measures Height and weight were measured on a physician’s scale (Detecto 339S; Cardinal Scale Co), and then BMI was calculated. All measurements were taken with the participants in lightweight clothing and without shoes.
Statistical Analysis An independent sample t-test was used to test the effects of sex, PROP status, and hot chili pepper user status for the continuous variables, and the c2 test was used for categorical variables, as appropriate. Subject characteristics were measured across ethnic groups by one-way analysis of March 2015 Volume 115 Number 3
variance. To predict energy intake, fat intake, and BMI, multiple linear regression models were used to fit with the covariates, age, sex, ethnicity, chili pepper score, and PROP mean. In order to test the normality and multicollinearity of variables, a normal plot of the residuals were examined and collinearity statistics were calculated in the regression model. Residuals and expected values were linearly plotted, which suggests agreement with normality. Also, according to the result of collinearity analysis, as all the variance inflation factors for independent variables are
Original Research
Relationship of 6-n-Propylthiouracil Taste Intensity and Chili Pepper Use with Body Mass Index, Energy Intake, and Fat Intake within an Ethnically Diverse Population Sung Eun Choi, PhD, RD; Jacqueline Chan, MS, RD ARTICLE INFORMATION Article history: Accepted 3 September 2014 Available online 20 November 2014
Keywords: 6-n-propylthiouracil Hot chili pepper Energy intake Fat intake Body mass index 2212-2672/Copyright ª 2015 by the Academy of Nutrition and Dietetics. http://dx.doi.org/10.1016/j.jand.2014.09.001
ABSTRACT Background One of the weight-loss strategies that has attracted attention is the use of spicy foods. It has been suggested that spicy food preference is related to a genetically predetermined sensitivity to the bitter compound 6-n-propylthiouracil (PROP). Objective Our aim was to examine the relationship of PROP taste intensity and hot chili pepper use with body mass index (BMI), energy intake, and fat intake. Design This study utilized a cross-sectional design. Participants/setting The sample included 350 subjects (154 male, 196 female) ages 18 to 55 years living in the New York City area. Main outcome measures BMI was calculated by measuring weight and height, and the sensitivity to PROP was evaluated using the PROP filter paper method. Subjects also rated the frequency of usage and preference for hot chili pepper using a chili pepper questionnaire. Their daily energy and fat intake were assessed using a food frequency questionnaire. Statistical analyses performed An independent sample t-test compared subject characteristics between groups based on sex, PROP status, and hot chili pepper user status for the continuous variables, and the c2 test was used for categorical variables. One-way analysis variance examined the differences in subject characteristics across four ethnicities. To predict BMI, energy intake, and fat intake, multiple linear regression models were fit with the covariates of age, sex, ethnicity, chili pepper score, and PROP mean. Results The values for BMI, energy intake, and fat intake of PROP tasters were significantly lower than those of PROP nontasters (P¼0.03, P135 food items all relating to the diet during the previous year in 10 categories: fruits and juices; vegetables and grains; meat, poultry, eggs and fish; mixed dishes; breads, salty snacks, spreads; breakfast cereals; sweets; dairy products; beverages; and foods to be added. The FFQ has been validated against 24-hour recall data.48,49 Upon completion of FFQ, registered dietitian nutritionists individually reviewed the FFQ and any discrepancies/questions were addressed. The daily intake per item was entered into the Food Processor software program (version 10.12, 2012, ESHA) to March 2015 Volume 115 Number 3
RESEARCH Please circle the appropriate answer to each question below. 1.
2.
3.
4. 5. 6.
How often do you eat all types of chili pepper in foods, including Mexican, Indian, Chinese, and other foods that contain chili pepper and cause tingling or burning? 1¼once a year or less 2¼less than once a month 3¼1-3 times per month 4¼Once a week 5¼3-4 times a week 6¼every day 7¼more than once a day How much do you like the taste of chili pepper in your food? 1 2 3 4 5 6 7 8 9 Dislike extremely Like extremely How much do you like the burn of chili pepper in your food? 1 2 3 4 5 6 7 8 9 Dislike extremely Like extremely I think chili pepper makes food taste better. True / False Without hot spices, I find that food tastes too bland. True / False I find it hard to appreciate the flavors of food when the food contains hot spices. True / False Thank you!
Figure. Chili pepper questionnaire used when categorizing chili pepper users and nonusers and evaluating chili pepper use and liking for adult subjects. Figure created using text from reference 16, by permission of Oxford University Press. analyze the daily energy intake and fat intake for each subject.
Chili Pepper Questionnaire The chili pepper questionnaire items16 developed by Lawless and colleagues (see Figure) were used to categorize chili pepper users and nonusers and to calculate a composite score of chili pepper use and liking (chili pepper score) in this study. On question 1 of the questionnaire, the subjects with responses of 1, 2, or 3 were categorized as chili pepper nonusers, and the subjects with responses of 5, 6, or 7 were categorized as chili pepper users. Subjects with the middle response of 4 (ie, once a week) were not included in the study to make the characteristics more distinct between the two categories.16 The chili pepper score was calculated by combining the responses from the six questions in the same way that was used in the study conducted by Lawless and colleagues.16
Anthropometric Measures Height and weight were measured on a physician’s scale (Detecto 339S; Cardinal Scale Co), and then BMI was calculated. All measurements were taken with the participants in lightweight clothing and without shoes.
Statistical Analysis An independent sample t-test was used to test the effects of sex, PROP status, and hot chili pepper user status for the continuous variables, and the c2 test was used for categorical variables, as appropriate. Subject characteristics were measured across ethnic groups by one-way analysis of March 2015 Volume 115 Number 3
variance. To predict energy intake, fat intake, and BMI, multiple linear regression models were used to fit with the covariates, age, sex, ethnicity, chili pepper score, and PROP mean. In order to test the normality and multicollinearity of variables, a normal plot of the residuals were examined and collinearity statistics were calculated in the regression model. Residuals and expected values were linearly plotted, which suggests agreement with normality. Also, according to the result of collinearity analysis, as all the variance inflation factors for independent variables are
![[Relationship among prop phenotype, body mass index, waist circumference, total body fat and food intake].](/assets/img/hold.png)
