There are very limited data concerning the influence of low-level trans fatty acid (TFA) intake on blood lipid levels. In this study, correlation of total and diene TFA intake with serum cholesterol levels was studied in young Japanese women. The mean intakes of total and diene TFAs were 0.36% and 0.05% of energy, respectively. There was a significant correlation between total fat intake and TFA intake. TFA intake was significantly correlated with erythrocyte TFA content. Total TFA intake was not correlated with total, LDL- or HDL-cholesterol levels. No correlatuon was found between diene TFA intake and cholesterol level. Total and diene TFA intake were not correlated with hemoglobin A1c or C-reactive protein levels. These results suggest that the average TFA intake of young Japanese women does not adversely affect serum cholesterol levels.