Dieting attitudes and behavior in an urban, high school student sample

Abstract

This study was conducted to evaluate dieting behaviors and concern about body size and shape in high school students of varying ethnic backgrounds, and relationships to taste enjoyment and consumption of dairy products. Subjects (n=785) were enrolled in Grades 8 through 12 in 6 different high schools in a metropolitan city. Students in one class per grade level in each school completed a questionnaire which sought information on age, ethnic background, the number of meals and snacks eaten per week, self-reported height, weight and desired weight, taste enjoyment of eight dairy products, and frequency of consumption of these products. The questionnaire also contained the dieting subscale (DS) of Garner and Garfinkel's Eating Attitudes Test (EAT-26), which assesses dieting behavior and concern about body size and shape. Subjects averaged 15.4±1.6 (mean ± SD) years of age. Ethnic background was caucasian in 37%, oriental in 38% and mixed or other in 25%. Mean self-reported body mass index (BMI) of males was lower than desired BMI (20.7±3.1 vs 21.8±3.4 kg/m2, P<0.001). Reported and desired BMIs of males, and the difference between them, did not vary by ethnic background. In contrast, the reported BMI of females was greater than desired BMI (20.1±2.4 vs 18.8±1.6 kg/m2, P<0.001). Reported BMI of caucasian females exceeded those of other groups (P<0.01), as did the difference between reported and desired BMI (P<0.01). Desired BMI, however, did not differ among ethnic groups. Mean scores on the DS increased with age in females (r=0.11, P=0.02), but not in males, and were higher in females than males (6.3±6.5 vs 2.3±3.2, P<0.001). Thirty-three percent of the young women and 7% of the young men had scores ≥8, which are said to represent abnormal attitudes. In females only, scores differed by ethnic background (P=0.013): oriental females had lower scores than those of caucasian or mixed ethnicity. However, when BMI was included as a covariate, the influence of ethnicity on DS scores was not significant. DS scores correlated significantly with reported BMI (r=.17, P<0.001) and with the difference between desired and reported BMI (r=−.38, p<0.001). In females only, DS scores were negatively associated with consumption of meals (r=−.14, P<0.01) and snacks (r=−.13, P<0.01). Although taste enjoyment of all dairy products combined was not associated with DS scores, enjoyment of whole milk and ice cream were negatively correlated (r=−.19, P<0.001 and r=−.15, P<0.001) and enjoyment of skim milk positively correlated (r=.17, P<0.001) with scores. Finally, reported consumption of ice cream (r=−.08, P=0.025) and milk (r=−.10, P=0.006) correlated negatively with DS scores. The results indicate gender differences in dieting attitudes and behaviors, and ethnic differences in females that appear to be due to body size differences. Supported by a grant from the Dairy Bureau of Canada.