Nonalcoholic fatty liver disease (NAFLD) is an emerging and important disease in Taiwan. However, the prevalence and clinical characteristics have not been studied well. The purpose of this study is to resolve the aforementioned problem.

[Study Subjects] Obesity was defined as the BMI value > 95 percentile by different age- and gender groups according to the standards of the Department of Health in Taiwan.

[Data Collection] The following data were obtained for each subject: age, gender, BMI, waist and hip circumference. BMI was calculated as body weight (kg)/ height (m2).

In fasting venous blood samples, we measured total serum bilirubin, alanine aminotransferase, aspartate aminotransferase, γ-glutamyltransferase, fasting glucose, triglyceride, total cholesterol,high-density lipoprotein cholesterol, insulin, glucose, and adiponectin.

[Liver Ultrasonography] All participants underwent an ultrasonographic study of the liver performed by one operator.

NAFLD was defined as the presence of an ultrasonographic pattern consistent with the following criteria: liver-kidney echo discrepancy, attenuated echo penetration and visibility of diaphragm, and obscure hepatic vessel structures.

Inclusion Criteria:

• diagnosis of fatty liver

Exclusion Criteria:

• other hepatic diseases

Obese children will be enrolled from elementary school and high school in Taiwan