Naoko Nishitani

Relationship of obesity to job stress and eating behavior in male Japanese workers

Objective:To examine a possible relationship between obesity, job stress, and eating behavior in male Japanese workers.Method:A questionnaire on life style, job stress, and eating behavior was conducted with 208 male workers aged 19–60 years (33.7±12.3 years) in a manufacturing industry in Japan. Height and weight were measured in an annual health examination. The relation between obesity, job stress, and eating behavior were analyzed between 141 nonobese subjects (BMI ⩽24.9 kg/m2) and 67 obese subjects (BMI ⩾25.0 kg/m2).Results:Obesity was associated with psychological stress responses of tension/anxiety, especially tension. Tension/anxiety was also related to job demands positively and job latitudes negatively. The eating behaviors of subjects with tension/anxiety resembled those of the obese subjects.Conclusions:The present study suggests that obese male Japanese workers tend to be in a stressful state from high job demands and low job latitudes in the workplace. Such stressful conditions may affect eating behaviors to eat much and contribute to obesity. Stress management might be necessary in the workplace for the prevention of obesity among male Japanese workers.

Eating behavior related to obesity and job stress in male Japanese workers.

OBJECTIVE We examined a possible relation among obesity, eating behavior, and job stress in male Japanese workers. METHODS A questionnaire survey on lifestyle, eating behavior, and job stress was conducted with 595 male daytime workers (19-60 y of age, mean +/- SD 41.8 +/- 12.6 y of age) in a synthetic-fiber manufacturing plant. The 431 non-obese men (body mass index <25.0 k/m(2), mean age 41.7 +/- 12.9 y) and 164 obese men (body mass index > or = 25.0 k/m(2), mean age 42.0 +/- 11.9 y) were examined in relation to obesity, eating behavior, and job stress. Body mass index was calculated from height and weight measured in an annual health check. RESULTS Obesity was associated with eating behaviors such as eating to satiety, eating fast, and substitution eating from irritability. These eating behaviors were related to high job demands of quantitative workload. The eating behaviors were also correlated with psychological stress responses of fatigue, tension/anxiety, and depression, which were associated with quantitative workload. CONCLUSION The present study suggests that high job demands of quantitative workload may be a factor related to eating behavior to eat a lot among male Japanese workers. Increased workplace stress from job strain may affect the workers through eating behaviors to eat a lot that contribute to obesity.

Characteristics of short sleeping time and eating behaviors related to obesity.

SUMMARY OBJECTIVE To clarify the relation between short sleeping time, obesity and eating behaviors in male workers. METHODS A self-completed questionnaire survey of 680 male daytime workers (age 19-60 years, mean age 42.9 ± 12.5 years) at a manufacturing plant was conducted in 2005. Subjects were divided into two groups by body mass index (BMI): 480 non-obese men with BMI of <25.0 kg/m(2) (mean age 42.8 ± 12.8 years) and 200 obese men with BMI of ≥25.0 kg/m(2) (mean age 43.3 ± 11.7 years). Basic attributes and living habits were then investigated, and the relation of eating behavior to each BMI level was analyzed. BMI and eating behaviors were also investigated in relation to sleeping time. RESULTS Sleeping time was significantly shorter in obese men than in non-obese men. Multiple regression analysis showed that sleep time as well as living with family were independent factors for greater BMI. BMI increased as sleeping hours became shorter in the order of ≥9 h, 8 h, 7 h, and ≤6 h. With shorter sleeping time, the mean eating behaviors scores also increased for cognition of constitution, substitution eating and drinking, feeling of satiety, meal contents, eating rhythm abnormalities, and eating style. The mean scores for these eating behaviors all increased with level of obesity, and these behaviors were characteristic of the obese men. CONCLUSIONS This study showed that people with short sleeping times tended to have eating behaviors of eating more, which can lead to obesity. Short sleeping time may contribute to eating much and then obesity.

Association of Psychological Stress Response of Fatigue with White Blood Cell Count in Male Daytime Workers

Relationships between work-related psychological and physical stress responses and counts of white blood cells (WBCs), neutrophils, and lymphocytes were investigated in 101 daytime workers. Counts of WBCs and neutrophils were positively associated with smoking and inversely correlated with high density lipoprotein (HDL)-cholesterol levels. Additionally, general fatigue score as measured by the profile of mood state was positively correlated with WBC and neutrophil counts whereas lymphocyte counts was not significantly associated with fatigue score. Multiple regression analysis showed that WBC count was significantly related to general fatigue, age, and HDL-cholesterol levels. Neutrophil count was significantly related to HDL-cholesterol levels and fatigue score. Among various psychological stress response variables, general fatigue may be a key determinant of low-grade inflammation as represented by increases of WBC and neutrophil counts.

Short Sleeping Time and Job Stress in Japanese White-Collar Workers

The aim of this study was to clarify the association between sleeping time and job stress in male Japanese workers. Male workers at one manufacturing plant were surveyed about job stress and sleeping time using a self- completed questionnaire. A total of 274 white-collar daytime workers were analyzed. Job stress factors and stress response were assessed using the Job Stress Questionnaire. Sleeping time on working days was divided into ≤ 5 h, 6 h, 7 h, and ≥ 8 h, and associations between job stress factors and stress response were analyzed. Shorter sleeping time was related to overtime work; about a quarter of those with sleep of ≤ 5 h worked more than 15 h overtime per week. Workers with shorter sleeping time, particularly those with ≤ 5 h sleeping time, were more likely to have job stress factors of quantitative workload and interpersonal conflict as well as psychological stress responses, such as anger, fatigue, tension/anxiety, and depressive symptoms. With shorter sleep, in subjects ≤ 39 years, scores of activity and fatigue decreased or increased respectively, whereas in those ≥ 40 years, scores for tension/anxiety and depressive symptoms increased. Shorter sleeping time was related to overtime work and increased job stress in male white-collar workers. Depression symptoms may be more closely associated with shorter sleeping times in workers aged ≥ 40. Adequate sleep duration is important for maintaining mental health.

Association between body mass index and high-sensitivity C-reactive protein in male Japanese

We divided subjects into hs-CRP of ≤1.0 mg/l and >1.0 mg/l, and investigated the relationship between hs-CRP and basic attributes, lifestyle and health checkup test results. In particular, hs-CRP increased significantly as BMI increased, and hs-CRP of >1.0 mg/l was seen in about 40% of people with BMI of ≥25 kg/m(2) and 75% with BMI of ≥ 30 kg/m(2). Persons with 3 or more abnormalities in BMI, blood pressure, serum lipid and glucose were found in 20.0% of those with hs-CRP >1.0 mg/l, while 4.3% in hs-CRP ≤ 1.0 mg/l. The present findings have suggested that hs-CRP > 1.0 mg/l can be an indicator for obesity-related risks in male Japanese.