Objective: Determine the prevalence of metabolic syndrome for comparison.
Material and Method: A cross-sectional survey of Nakhon Sawan population aged 15 years and over was conducted in March 2002. There were 636 persons included in the present study, age range from 15 to 87 years, and mean age of 41.4 + 16.7 years.
Results: The prevalence of metabolic syndrome using World Health Organization (WHO), The National Cholesterol Education Program (NCEP) Expert Panel on detection, Evaluation, and Treatment of High Blood Cholesterol In Adults (Adult Treatment Panel III, ATP III), and International Diabetes Federation (IDF) definition was 6.2, 20.0, and 18.7%, respectively. This prevalence was high compared with the previous study in Thailand and the estimated global metabolic syndrome for adults above 20 years of age. Women and elders had a higher prevalence than men and youngsters. The authors should search for Thai cut-off values of abdominal obesity in children and adults to have the correct data for public health plan and management. This is because there are variations among the different ethnic background and countries, even within Asia.
Conclusion: The prevalence of metabolic syndrome was high. The interventions in prevention and management of the metabolic syndrome should be started for overweight children.

Keywords: Metabolic syndrome, Central obesity, Prevalence, Population, Thailand