Risk for non-obese Japanese workers to develop metabolic syndrome.

With regard to metabolic syndrome-related risks (MS risks), obese workers have been the focus of attention, and less attention has been paid to non-obese subjects as if they were free from the risks. The present analysis was initiated to know if no-obesity means no-MS risks. Participants of the study were 804 male workers, who showed no pathological findings in 12 MS-related and other health parameters in 2003, and had complete sets of data in 2008. They were classified by BMI in 2003 into lean (< 18.5), normal (> or = 18.5 to < 25) and obese groups (> or =25). Proportion of MS in 2008 was examined by use of the second phase of MS criteria. Proportions for the lean, normal and obese subjects who met MS criteria in 2008 were 3.2, 4.8 and 5.3%, respectively, with no significant difference in proportions among them. In the non-obese (i.e., lean+normal) group, age was not significantly influential to increase BMI. Thus, the MS risk exists even in non-obese young workers. Anti-MS effort should be directed not only to obese but to non-obese workers, and care should be extended irrespective of ages.