New employees gain weight in the first 3 years at work: relationship between lifestyle and body weight changes in newly hired male employees in Japan

Objectives To evaluate lifestyle and weight changes in new male employees of Japanese companies and clarify the effects of environmental and lifestyle changes on weight changes in early years after joining the company. Methods Design: mixed research We analyzed health checkup results and lifestyle questionnaires of 160 male graduates hired by a particular company between fiscal years 2009 and 2012. The data obtained included health examinations from the time of the job offer to the fourth year at the company. Weight changes were analyzed using a Friedman Test. Lifestyle questionnaire was analyzed using a McNemar test. Twelve male employees who had been with the company for 5-10 years were interviewed about their lives before and after joining. The results were transcribed and analyzed using the Steps for Coding and Theorization method. Results Compared with employees' weight at the time of the job offer, their weight at the time of joining the company and in the second and third years increased significantly. (P value <0.001) An increasing number of participants who ate dinner late, missed opportunities for exercise, and did not get sufficient sleep. Interview results indicated overtime, commuting, work-related drinking parties among new employees led to late dinners, difficulty maintaining exercise habits, and stress at work led to overeating. Conclusions New employees gained weight during their first three years at the company, and lifestyle changes such as overtime work, late dinners due to drinking parties, and loss of opportunities for exercise during the same period had an impact.