Relationship between screen time and nutrient intake in Japanese children and adolescents: a cross-sectional observational study.

BACKGROUND: Sedentary behaviors have recently become an important public health issue. We aimed to investigate the relationship between screen time and nutrient intake in children and adolescents. METHODS: The present study was conducted in 2013. Data were collected from children and adolescents aged between 6 and 15 years old in Shika town. Questionnaires were distributed to 1459 subjects, 1414 of whom participated in the study (96.9%). Sedentary behaviors were assessed based on participants' screen behaviors (television (TV) viewing, personal computer (PC) use, and mobile phone (MP) use). The main outcomes were the intake of nutrients from a validated food frequency questionnaire. Analysis of covariance (ANCOVA) was used to examine the significance of differences in nutrient intake estimates. Multivariate linear regression analyses, adjusting for age, BMI, and physical activity, were used to provide parameter estimates (ß) and 95% CI for the relationship between screen time and nutrient intake. RESULTS: In boys, longer TV viewing times correlated or tended to correlate with a lower intake of protein, potassium, calcium, iron, vitamin K, vitamin B-2, and total dietary fiber. In girls, longer TV viewing times correlated with a lower intake of protein, sodium, calcium, vitamin D, and vitamin B-2. Longer TV viewing times correlated with a higher intake of n-6 fatty acids in girls. PC use was related or tended to be related to a lower intake of potassium, iron, vitamin K, and folic acid in boys, but not in girls. A relationship was observed between MP use and a lower intake of vitamin K in boys, and MP use and a higher intake of vitamin D in girls. CONCLUSIONS: The present results revealed that longer TV viewing times are associated with less protein, minerals, vitamins, and total dietary fiber intake in children and adolescents. It was also revealed that boys with PC use have less minerals and vitamins. These results support the need to design intervention programs that focus on decreasing TV viewing time in both sexes and PC use in boys while encouraging adherence to dietary guidelines among children and adolescents.

The associations between lifestyles and mental health using the General Health Questionnaire 12-items are different dependently on age and sex: a population-based cross-sectional study in Kanazawa, Japan.

OBJECTIVES: The aim of this study was to examine potential differences of the associations between mental health and lifestyle factors across a wide range of age. METHODS: In August/September 2011, data were collected from 4693 males (age 51.6 ± 19.5) and 5678 females (age 52.4 ± 19.4) living in Kanazawa, Japan. A cross-sectional community-based survey was conducted with self-administered questionnaire including the General Health Questionnaire (GHQ) 12-item version, sociodemographic, and lifestyle factors. Associations between the GHQ scores and other variables were examined using two-way analysis of variance (ANOVA) followed by multiple comparisons and logistic regression stratified by age and gender. RESULTS: Multiple comparisons indicated that people aged 20-39 or 40-64 had higher GHQ scores than older aged. The two-way ANOVA revealed significant interaction between body mass index and age group, and between exercise and age group. Overweight or underweight males aged 40-64 had poorer mental health than those at normal weight. In the elderly, being underweight was significantly associated with poor mental health. There were no significant effects of exercise on mental health for young adults. The logistic regression showed significant negative effects of short-time sleep in adults. CONCLUSIONS: The associations between mental health and lifestyles differ across age groups. Further study is needed to reveal effects of aging on lifestyle and mental health with a longitudinal design.

Common risk factors for changes in body weight and psychological well-being in Japanese male middle-aged workers.

OBJECTIVES: Overweight and poor psychological well-being are becoming serious health issues in the Japanese workplace. Concurrence of those physical and mental conditions has been pointed out, especially in middle-aged workers. Therefore, we tried to determine common risk factors for body weight gain and the deterioration of psychological well-being in male middle-aged office workers using a five-year follow-up study. METHODS: We administered General Health Questionnaire-12 (GHQ-12) as an indicator of psychological well-being to 110 male workers with ages ranging from 40-59 years, and analyzed the influence of several psychological factors, namely sense of coherence (SOC), health locus of control (HLC), and lifestyle variables such as exercise frequency, alcohol intake, smoking status, and dietary intake on changes of body mass index and GHQ-12 score. RESULTS: McNemar's chi-squared test showed significant concurrence of weight gain and deterioration of psychological well-being after five-year follow-up. Low-SOC score, low frequency of exercise, and high-dietary intake at supper were significantly associated with both weight gain and poorer psychological well-being in workers, results which were supported by multiple regression analysis. CONCLUSIONS: These results suggest that exercise and calorie restriction seem to prevent weight gain and promote psychological well-being in workers. Low SOC, which implies difficulty in coping with stress, may be an important risk factor not only for deterioration of psychological well-being but also for becoming overweight. These assumptions must be confirmed by conducting future intervention studies on SOC and lifestyle including exercise and eating behavior.

Psychological factors including sense of coherence and some lifestyles are related to general health questionnaire-12 (GHQ-12) in elderly workers in Japan.

OBJECTIVES: The number of elderly workers has also been increasing and poor psychological well-being in elderly workers has been reported. The aim of this study is to elucidate the factors that are related to poor psychological well-being in elderly workers. METHODS: We administered General Health Questionnaire-12 (GHQ-12) as an indicator of psychological well-being to 330 male elderly workers in the age range of 50-69, and analyzed different psychological factors, namely sense of coherence (SOC), and physical and lifestyle variables such as blood pressure, serum total cholesterol, smoking frequency, alcohol intake, exercise frequency, and body mass index (BMI) that are related to GHQ-12. RESULTS: When the cut-off point of GHQ-12 was 2/3, 97 workers who showed high GHQ-12 score were classified as one group having poor psychological well-being. A statistically significantly lower SOC score, higher stress score, lower frequency of exercise, higher smoking score and higher BMI, but not longer working hours or higher shift work score in the workers with higher GHQ-12 scores were observed than in the workers with normal GHQ-12 scores. Multiple logistic regression analysis showed that the low SCO score, low frequency of exercise, high smoking frequency and high BMI significantly contributed to the high GHQ-12 score. CONCLUSIONS: A low SOC score in elderly workers is assumed to be directly related to poor psychological well-being, or via the development of lifestyle problems such as lack of exercise, obesity, and smoking in elderly workers. This assumption must be confirmed by conducting future intervention studies on lifestyle.

[The effects of nutrition and life-style on calcaneal bone mass in high school students].

OBJECTIVE: To clarify the effects of nutrient/food intake and lifestyle, especially exercise, on calcaneal bone mass in both male and female high school students. METHODS: A total of 798 healthy Japanese high school students (281 boys and 517 girls) were recruited, and their calcaneal bone was assessed by ultrasound using Lunar Achilles. The subjects were thereby divided into a lower bone mass group and a normal bone mass group according to stiffness at the cut-off level of 90 for the boys, and 77 for the girls. Information on lifestyle including frequency of food consumption and regular exercise during the period at junior high school and high school was collected by questionnaire. Nutrient intake was assessed by a semi-quantitative food frequency questionnaire. RESULTS: 1. The intake of total energy and fat in the lower bone mass group was lower than in the normal bone mass group in both sexes. 2. The frequency of subjects not consuming milk in the lower bone mass group was higher than in the normal bone mass group in both sexes. In the boys, the frequency of the subjects who liked to eat green vegetables in the lower bone mass group was lower in the normal bone mass group. 3. The mean stiffness for subjects undertaking exercise during junior high school was higher than in subjects not exercising, even after adjustment for age in both sexes. The frequency of subjects with a habit of sun bathing in the lower bone mass group was significantly lower than in the normal bone mass group in the girls. 4. An analysis using a logistic model was performed to select the factors related to lower bone mass without being confounded with other factors. Lower energy intake in boys and lower fat intake, no exercise during high school life and no milk consumption in girls were each independently related to lower bone mass. CONCLUSION: These results suggest that nutrition and exercise habit affect calcaneal bone mass in high school students of both sexes, especially milk consumption being an important factor related to bone mass in girls.