Associations between lifestyle behaviour changes and the optimal well-being of middle-aged Japanese individuals.

BACKGROUND Psychological well-being has been associated with reduced mortality rates in both healthy and diseased populations. However, there is considerably less evidence on the effect of lifestyle behaviours on positive health outcomes such as well-being. This study examines the association between lifestyle behaviours and optimal well-being. METHODS From a total of 4324 Japanese individuals who participated in an annual health check-up in 2017, this study recruited 2295 participants (mean age: 49.3 ± 8.4 years; female: 54.3%) without a history of cerebrovascular, cardiovascular, or chronic renal disease and not on medication for hypertension, diabetes, or dyslipidaemia. The World Health Organization-Five Well-Being Index (WHO-5) scores were compared to self-reported scores on each of the following items: dietary habits, physical activity, smoking, alcohol consumption, and sleep quality. Logistic regression analysis was used to examine the association between optimal well-being (the top quartile of WHO-5 scores) and individual lifestyle behaviours. The association between change in dietary habits and physical activity from 2016 to 2017 and optimal well-being was also investigated. RESULTS Good dietary habits and regular physical activity were associated with higher raw WHO-5 scores and were positively associated with optimal well-being after adjusting for age, sex, body mass index (BMI), and sleep quality. Raw WHO-5 scores were significantly higher in those who maintained good dietary and physical activity behaviours than in those who did not. Furthermore, maintaining regular physical activity for two years was positively associated with optimal well-being, after adjusting for age, sex, BMI, and sleep quality. CONCLUSION These results demonstrate that not only currently practising good dietary and physical activity behaviours but also maintaining such behaviours over time is associated with optimal well-being. Maintaining good lifestyle behaviours, particularly regarding physical activity, could potentially improve people's well-being.