Similarities and discrepancies between commercially available bioelectrical impedance analysis system and dual-energy X-ray absorptiometry for body composition assessment in 10-14-year-old children.

A variety of easy-to-use commercial bioelectrical impedance appliances are available. The aim of this study was to examine the usefulness of a commercially available body composition meter using bioelectrical impedance analysis (BIA) by comparing its measurement results with those obtained from dual-energy X-ray absorptiometry (DXA). The participants were 443 children aged from 10 to 14 years (226 boys and 217 girls). Fat mass, fat-free mass, lean body mass, percentage of body fat, and bone mineral contents were evaluated for all participants using BIA and DXA. The agreement in the anthropometric data obtained from both devices was analyzed using correlation analysis, intraclass correlation coefficient (ICC), Lin's concordance correlation coefficient (CCC), Bland-Altman plots, and ordinary least products regression analysis. Equivalence between both devices was tested by two one-sided t-test. All measured indicators showed strong linear correlations between the two measurement systems (r, 0.853-1.000). Fat mass, fat-free mass, and lean body mass showed absolute concordance (ICC, 0.902-0.972; Lin's CCC, 0.902-0.972). BIA overestimated bone mineral content (62.7-66.5%) and underestimated percentage of body fat (- 8.9 to - 0.8%), lean body mass (- 3.5 to - 1.8%), and body mass (- 0.8 to - 0.5%). For fat mass and fat-free mass, the overestimate or underestimate varied according to the sex and statistical analysis test. Bland-Altman analysis and ordinary least products analysis showed fixed bias and proportional bias in all indicators. Results according to quartiles of body mass index showed poor agreement for fat mass and percentage of body fat in both boys and girls in the lowest body mass index quartile. The present results revealed strong linear correlations between BIA and DXA, which confirmed the validity of the present single-frequency BIA-derived parameters. Our results suggest that BIA cannot provide the exact same values as DXA for some body composition parameters, but that performance is sufficient for longitudinal use within an individual for daily health management and monitoring.

Associations among perceived health competence, effortful control, self-control, and personality traits in Japanese university students.

Perceived health competence is thought to contribute to lifelong healthy behavior. However, the factors that affect perceived health competence have not been investigated. We investigated the associations among perceived health competence, effortful control, self-control, and personality traits in university students and proposed a model of how these factors affect perceived health competence. The participants were 320 Japanese university students who completed a questionnaire regarding their height, weight, perceived health competence, effortful control, self-control, and personality traits. The three-step multiple regression analysis showed that effortful control was positively associated with the perceived health competence, and self-control was positively with, and impulsivity was inversely associated with effortful control respectively, indicating that effortful control was an intermediate factor. Structural equation modeling showed a good fit for both genders, with a common path for both genders to perceived health competence via effortful control and a different involvement of personality traits for men and women. These results suggest that effortful control is directly associated with perceived health competence; in addition, both self-control and impulsiveness are indirectly associated with perceived health competence via effortful control.

Association between the recognition of muscle mass and exercise habits or eating behaviors in female college students.

This study aimed to examine the association between muscle mass and perception of body shape, desired body shape, physical strength, exercise habits, and eating behaviors. Height, weight, and body composition in 270 female university students were measured. The questionnaire on body shape perception, desired body shape, dieting experience, current, and past exercise habits, exercise preference, and eating behaviors were administered. The analysis of covariance with body fat mass as the covariate found that the skeletal muscle index (SMI) was different among each group on each of body perception or desired body shape (all, p < 0.001). In the post hoc test on body shape perception, the SMI in "obese" was significantly more than that in "slim" (p < 0.001) and "normal" (p < 0.001). In the desired body shape, the SMI in "become thin" was more than that in "maintain as current shape" (p < 0.001). Further, a significant difference was found among the categories of diet experience, with body fat mass as the covariate. In the post hoc test, the SMI in "yes" was more than that in "no" (p < 0.001). These results indicate that not only body fat mass but skeletal muscle mass drives young females' desire for thinness even with exercise advantages.

Attitude toward breakfast mediates the associations of wake time and appetite for breakfast with frequency of eating breakfast.

PURPOSE: We investigated associations among attitude toward breakfast, appetite for breakfast, wake time, personality traits, self-esteem, and frequency of eating breakfast in university students and proposed a model of factors affecting the frequency of eating breakfast. METHODS: The participants, 555 Japanese university students (177 men, 378 women), completed a questionnaire about their height and weight, living with family, wake time, frequency of eating breakfast, appetite for breakfast, attitude toward breakfast, personality traits, and self-esteem. Appetite for breakfast was evaluated with a four-point Likert-type scale. Attitude toward breakfast was assessed with a 13-item questionnaire using a five-point Likert-type scale; responses to the items were summed, and divided by the number of items to produce a score. RESULTS: Multiple linear regression analysis showed that frequency of eating breakfast was positively associated with appetite for breakfast and attitude toward breakfast, and inversely associated with wake time. Wake time was inversely associated with attitude toward breakfast, and appetite for breakfast was positively associated with attitude toward breakfast. Structural equation modeling showed that the structured model based on the multiple regression analysis was a good fit for both men (chi-square value to the degrees of freedom [χ2/df] = 1.096, root mean square error of approximation [RMSEA] = 0.023) and women (χ2/df = 1.510, RMSEA = 0.037). CONCLUSIONS: These results suggest that wake time and appetite for breakfast are directly associated with frequency of eating breakfast. Attitude toward breakfast mediates the indirect association between frequency of eating breakfast and both wake time and appetite for breakfast. LEVEL OF EVIDENCE: V, cross-sectional descriptive study.

Psychometric properties of the Japanese version of the Dutch Eating Behavior Questionnaire for Children.

This study aimed to evaluate the psychometric properties of the 20-item Japanese version of the Dutch Eating Behavior Questionnaire for Children (DEBQ-C). A population-based sample of 502 Japanese school children who were fifth- and sixth-graders in elementary schools and first- and second-graders in junior high schools was assessed. A sample was randomly split into two subsamples, one for exploratory factor analysis (EFA) and another for confirmatory factor analysis (CFA). Internal consistency estimates for subscales (restrained, emotional, and external) were evaluated using Cronbach's alpha. Measurement invariance was examined across each subgroup (genders: boys and girls, school categories: elementary school and junior high school, body mass index (BMI) categories: underweight, normal weight, and overweight) by using multi-group CFA. The Japanese version of the DEBQ-C demonstrates good results of item analysis. The three-factor structure of the original DEBQ-C was supported by both EFA and CFA. The reliability of each factor was also satisfied (restrained: α = 0.86, emotional: α = 0.90, external: α = 0.86). Results of multi-group confirmatory factor analysis supported its metric and scalar or partial scalar measurement invariance across all subgroups. In gender subgroup, girls scored higher on restrained eating. In school subgroup, junior high school children scored higher on emotional and external eating. In BMI subgroup, overweight children scored higher on restrained eating. These findings suggest that the Japanese version of the DEBQ-C is a psychometrically valid and reliable instrument for assessing eating behaviors across gender, school categories, and BMI categories in Japanese children.

Association of anthropometric status, perceived stress, and personality traits with eating behavior in university students.

PURPOSE: We investigated the association of anthropometric status, perceived stress, and personality traits with eating behavior in university students. METHODS: The participants, 1546 Japanese university students (964 males, 582 females), completed a questionnaire which asked for their current height and weight, ideal height and weight, eating behaviors, perceived stress, and personality traits. RESULTS: Restrained eating was higher in normal-weight participants compared with underweight participants in both males and females (p < 0.001, both males and females). Restrained eating in normal-weight males was significantly lower in normal-weight females (p < 0.001). In addition, normal-weight males reported less stress than normal-weight females (anxiety/uncertainty, p = 0.037; tiredness/physical responses, p < 0.001; autonomic symptoms, p < 0.001; depression/feeling, p < 0.001) and underweight males (tiredness/physical responses, p = 0.018; autonomic symptoms, p = 0.001). Moreover, among normal-weight males, neuroticism was significantly lower compared with normal-weight females (p < 0.001). In multiple regression analysis, male participants revealed positive association between restrained eating and body mass index (ß = 0.199, p < 0.001) or body mass index difference (ß = - 0.170, p = 0.001). In contrast, female revealed more significant associations between emotional and external eating and perceived stress or personality traits compared with males. CONCLUSIONS: These results indicate that associations between eating behavior and anthropometric status or psychological factors are different by each eating behavior, which is partly influenced by gender difference. LEVEL OF EVIDENCE: V, cross-sectional descriptive study.

Association of social support with gratitude and sense of coherence in Japanese young women: a cross-sectional study.

PURPOSE: Recent studies have shown that perceived social support is associated with gratitude and sense of coherence, but evidence for this concept remains scarce. In the present study, we investigated relationships between social support, gratitude, and sense of coherence, focusing on the construct of and source of social support among young women. METHODS: The study was conducted in 2014 in Japan. Participants comprised 208 female university students (aged 19.9 ± 1.1 years), who completed a self-administered anonymous questionnaire regarding perceived social support, gratitude, and sense of coherence. RESULTS: Emotional and instrumental social support from acquaintances were found to be lower than those from family and friends. Gratitude was positively correlated with all forms of social support except instrumental social support from acquaintances. However, sense of coherence was positively correlated with both emotional and instrumental social support from family and only emotional social support from acquaintances. Multiple regression analysis showed that emotional support from family and emotional support from acquaintances were positively associated with gratitude whereas emotional support from family was associated with sense of coherence. CONCLUSION: These results indicate that emotional social support from family was related to both gratitude and sense of coherence.

Cardiovascular response to short-term fasting in menstrual phases in young women: an observational study.

BACKGROUND: Menstrual cycle-related symptoms are an important health issue for many women, and some may affect cardiac autonomic regulation. In the present study, we evaluated the cardiovascular and physiological stress response to 12-h short-term fasting in the menstrual phases of healthy young women. METHODS: We performed a randomized crossover study. Subjects were seven female university students (age: 22.3 ± 1.0 years). The experiments comprised four sessions: meal intake in the follicular phase, meal intake in the luteal phase, fasting in the follicular phase, and fasting in the luteal phase. All subjects participated in a total of four experimental sessions during two successive phases (follicular and luteal phase in the same menstrual cycle, or luteal phase and follicular phase in the next menstrual cycle) according to a randomized crossover design. R-R intervals were continuously recorded before and after meals, and power spectral analysis of heart rate variability was performed. Other physiological data were obtained before and 20, 40, 60, and 80 min after meal intake or after the corresponding time point of meal intake (fasting in the follicular or luteal phase). RESULTS: Heart rate decreased during fasting in the follicular and luteal phases. High frequency power increased during fasting in the follicular and luteal phases. In addition, salivary cortisol concentrations decreased during fasting in the luteal phase. CONCLUSIONS: In the present study, short-term fasting resulted in higher parasympathetic activity and lower cortisol levels in the luteal phase in these young women. These results indicate a possibility to produce an anti-stress effect in the luteal phase, which may reduce menstrual symptoms.

Influences of peers' and family members' body shapes on perception of body image and desire for thinness in Japanese female students.

PURPOSE: The present study investigated the influence of peers' and family members' body shapes on the perception of body image and desire for thinness in Japanese female students. METHODS: The study included 342 female, Japanese university students between the ages of 18 years and 22 years. They completed an anonymous questionnaire, which included questions related to anthropometry and body perception. Eating behavior was assessed by the Japanese version of the Eating Attitude Test-26. RESULTS: Many students overestimated their body shape (81.2% of underweight students and 74.6% of normal students) and had a desire for thinness (41.0% of underweight students, 88.2% of normal students, and 100% of overweight students). One of the main reasons for the overestimation of their body shape was comparison with others. Participants who were interested in a friend's body shape were almost three times more likely to have a desire for thinness than those who were not interested in a female friend's body shape (odds ratio: 3.06, P=0.014). CONCLUSION: The results indicate a possibility that a female Japanese student's young female friends' body shapes, influences her desire for thinness or her perception of her own body shape.

Eating behavior and perception of body shape in Japanese university students.

PURPOSE: We investigated the relationship between eating behavior measured by the Dutch Eating Behaviour Questionnaire (DEBQ) and perception of body shape, examining the current physical status and 'ideal' physical parameters in females and males. METHODS: The participants, 548 Japanese university students (age 19.2 ± 0.9 years, mean ± SD; 252 males, 296 females), completed a questionnaire which asked for their current physical status (e.g., weight and height), their ideal physical parameters, their perception of their current body shape, their ideal body shape, and their eating behaviors. RESULTS: The ideal weight and ideal body mass index (BMI) were significantly higher than the current weight and BMI in the males, but significantly lower in the females. Among the females, the ideal body shape was smaller than their perception of current body shape. The DEBQ scores for restrained, emotional, and external eating were higher in the females than the males among the normal-weight participants, and among the underweight participants, the restrained eating and external eating scores were higher in the females than the males. Restrained eating was negatively associated with the discrepancy between the current and ideal weight, BMI, and body shape in both the males and females. Emotional eating was negatively associated with the discrepancy in current/ideal BMI and body shape only in the females. CONCLUSIONS: At least in Japanese university students, the gender differences in ideal body shape are related to eating behavior.

Relationship of a desire of thinness and eating behavior among Japanese underweight female students.

OBJECTIVE: We conducted a questionnaire survey among Japanese female students to explore the influence of a desire for thinness and dietary behaviors on the development of eating disorders. METHODS: Self-reported measures of socio-demographic characteristics, body weight perception, height and weight, and dietary and exercise behavior were completed by 631 female university students at 6 universities in Kyoto, Japan. RESULTS: Many students had a desire for thinness (underweight students, 51.7 %; normal-weight students, 88.8 %), whereas ideal weight and body mass index were lower in the students with a desire for thinness than the students without a desire for thinness, and were also lower in the underweight students than the normal-weight students. The eating attitude test (EAT-26) scores of underweight students with a desire for thinness were higher than those of the normal-weight students with a desire for thinness. As a result of a logistic regression analysis, underweight, desire for thinness, and experience with weight control were positively associated with eating problems. Further, the association of eating problems increased along with the increase in the number of factors (underweight, desire for thinness, and experience with weight control). CONCLUSIONS: These results indicate that underweight females have strong associations with eating problems.

[Association between normal weight obesity and diet behaviors in female students].

OBJECTIVES: The association between normal weight obesity and diet behavior and physical activity in female students was investigated in this study. METHODS: The subjects were 530 female students aged 18-21 years from 6 universities in the Kyoto Prefecture, Japan. From January to July, 2010, the body fat and walk counts of these students were measured, and they answered a questionnaire. The questionnaire included questions on life environment, perception of body shape, dieting experiences, physical activities, sleeping habits, and diet behaviors. The Eating Attitude Test-26 (EAT-26) was used to evaluate diet behavior. Students with normal weight (18.5 < or = body mass index < 25 kg/m2; n = 439) were divided into high (n = 115), middle (n = 213), and low (n = 111) groups according to their percentage of body fat. Further, a comparative analysis was performed among the 3 groups. RESULTS: From the results of the questionnaire, perception of body shape, desire for a particular body shape, reason for weight loss, success or failure in dieting, and time for sleep were significantly different among the 3 groups. Differences in physical activity were not significant among the groups. Factor III (Oral control) of EAT-26 was higher in the high group than in the low group. CONCLUSION: High body fat was associated with diet behavior and a desire to lose weight in normal weight students. These results indicate that health education is necessary to establish and maintain appropriate body fat composition and dietary habits.

Combined influence of media use on subjective health in elementary school children in Japan: a population-based study.

BACKGROUND: In recent years in Japan, electronic games, home computers, and the internet have assumed an important place in people's lives, even for elementary school children. Subjective health complaints have also become a problem among children. In the present study, we investigated the relationship between media use and health status in elementary school children in Japan. METHODS: A cross-sectional school-based population survey was conducted in 2009 with a sample of fourth-, fifth-, and sixth-grade children (age range: 10-12 years old) in elementary schools in Japan (n = 3,464). Self-reported health, lifestyle habits, and time spent using media were assessed. RESULTS: The use of games, television, and personal computers was significantly associated with lifestyle (p < 0.05) and subjective health (p < 0.05). In addition, the use of games, the use of television, and the use of personal computers were mutually associated. The greater the number of media used for more than 1 hour was, the higher the odds ratio of the association of media use with unhealthy lifestyle and subjective health complaints was. The plural use of these media had stronger associations with unhealthy lifestyle and subjective health complaints. CONCLUSIONS: Game, television, and personal-computer use were mutually associated, and the plural use of these media had stronger associations with unhealthy lifestyle and subjective health complaints. Excessive use of media might be a risk for unhealthy lifestyle and subjective health complaints.