The liver is an important organ closely associated with lipid and glucose metabolism. This study was performed to clarify the relationship between periodontitis and hepatic condition in apparently healthy Japanese women. A cross-sectional study was performed on 172 apparently healthy, dentulous Japanese women (20-59 years old) who attended a health promotion program at Fukuoka Health Promotion Center. After multivariate adjustment for age, smoking history and oral hygiene, which were known risk factors for periodontitis, the incidence of periodontitis (deepest probing depth > or =4 mm) in females was significantly increased with elevated serum levels of aspartate aminotransferase (AST, p < 0.01), alanine aminotransferase (ALT, p < 0.01) and cholinesterase (p < 0.001), and an AST-to-ALT ratio of less than one (p = 0.02). Further adjustment for either body mass index (BMI) or percent body fat did not attenuate these relationships. These results suggest that hepatic steatosis is associated with periodontitis in Japanese women.