Introduction The health guidance system that focused on Metabolic Syndrome (MetS) for people over 40 years old was launched in 2008 in Japan. This study aimed to evaluate the health guidance courses and the cost effectiveness of the program.

Methods The three courses of the health guidance program for male workers of an automobile parts manufacturing company (age 19 to 60) having the risk of metabolic syndrome were conducted in May – July 2016, November – January 2016 and January – March 2017. Each course of the health guidance was held for three months in which lectures related to MetS and exercises were taught. In addition, physical measurements were recorded. Health education concerning hypertension and salt intake was held in the third course. The indicators of the effects of the health guidance were taken as the amount of change in weight, blood pressure and the measurement of the abdominal circumference. We conducted this study with the approval of the ethics committee of the university that I belonged to.

Results Nmber of subjects was 199 male workers. The cost of one course was 6900–7550 Japanese Yen/person. While there were no significant differences between the effectiveness of the health guidance courses seasonally (summer/winter) nor the age of the workers, the effects of the health guidance were different from the first and third courses from that of the 2d course which was conducted around New Year’s and was the worst of the three. The first course that was held in spring was the most effective and had the highest cost effectiveness.

Conclusion Previous research reported that there was seasonal variation in body weight and HbA1c. In addition to the influence of seasonal fluctuation, further analysis involving factors of the subjects’ health knowledge and physical activity is necessary.