摘要:Background: Trans fatty acids are considered to impair health and some ω fatty acids are protective against atherosclerosis and diabetes mellitus. Trans fatty acids are said to be formed by the partial hydrogenation of vegetable oils. Some amounts are produced in digestive organs of ruminants and present in dairy products or meat. It is important how much these intaken fatty acids influence their plasma levels. Methods: Plasma levels of fatty acids including transforms of healthy old men are measured by gas chromatography and correlations between various foods intakes and plasma levels of trans fatty acids, and ω fatty acids are examined. Results: Intake of fish resulted in increase in plasma levels of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) but intake of meat such as beef, cow and chicken meat did not increase plasma levels of arachidonic acid (AA). Intakes of oils increased plasma levels of dihomo-g-linolenic acid significantly and AA to some extent. Conclusion: Plasma levels of EPA and DHA increased upon intakes of fish in Japanese old men. Oil intake but not meat intake increased DGLA significantly. These results may explain low incidence of cardiovascular diseases in Japanese people compared with American people whose plasma levels of DHA and EPA are lower.