Lack of Leisure-Time Physical Activity in Non-Obese Japanese Men with Components of Metabolic Syndrome

A focus exclusively on waist circumference, the main component used in the diagnosis of metabolic syndrome (MetS), may lead to ignoring non-obese individuals with other MetS components, including high levels of blood pressure, fasting blood glucose, and triglycerides and low levels of high-density lipoprotein. This study investigated lifestyles and eating behaviors among non-obese individuals with components of MetS. Of the 918 Japanese male workers, 151 subjects (16.4%) had a waist circumference < 85 cm with more than one MetS component. This non-obese high-risk group for MetS gained weight in adulthood, consume alcohol, and engage in less leisure-time physical activity compared to 317 subjects (34.5%) with a waist circumference < 85 cm and without MetS components (p < 0.05). The remaining 450 subjects (49%) were obese with a waist circumference ≥ 85, including 93 men with MetS. A lack of leisure-time physical activity was associated with the non-obese high-risk group for MetS [odds ratio 1.59, 95% confidence interval 1.02 - 2.49] compared to the 317 non-obese men without MetS (reference group). Such a difference in physical activity was not found between the 450 obese subjects and the reference group. Instead, eating behaviors, such as eating rapidly, preference for fatty foods, and eating out for dinner, were significantly associated with MetS. Thus, men with smaller waist circumferences and any MetS component should be carefully monitored for physical activity to prevent further development of MetS, while men with larger waist circumferences including MetS need to be monitored for unfavorable eating behaviors.