Plasma Fatty Acid Composition in Men over 50 in the USA and Japan

Abstract

Background: Coronary heart disease (CHD) rates differ markedly between the US and Japan. Fatty acid profiles have been linked to risk for CHD. Few studies have compared the plasma fatty acid composition, including trans fatty acids, in Japanese and US subjects. Methods: Fasting blood samples were taken from healthy older (>age 50) American (n = 76) and Japanese (n = 44) men, and plasma levels of 23 fatty acids were analyzed by gas chromatography and expressed as a percent of total fatty acids. Results: As expected, plasma levels of long-chain ω3 fatty acids (docosahexaenoic and eicosapentaenoic acids, DHA and EPA) were higher in Japanese men and ω6 fatty acids (e.g., arachidonic acid, AA) were lower compared with American men. Plasma levels of the major industrially-produced trans fatty acids (IP-TFAs; elaidic and linoelaidic acids) were far higher in American men, and levels of the potentially cardioprotective, primarily ruminant-derived trans fatty acid palmitoelaidic acid (POA) were higher in Japanese. Plasma levels of saturated or monounsaturated fatty acids were also higher in the American men. Conclusion: There are multiple differences in plasma fatty acid profiles between American and Japanese older men. The higher levels of DHA and EPA, along with the lower levels of the IP-TFAs, are consistent with the markedly lower risk for coronary heart disease in Japan vs. the US.

Effects of Various Foods Intakes on Plasma Levels of Trans Fatty Acids in Japanese Old Men

“…We found that IP-trans fatty acids were lower in Japan vs the US [8]. The reported intake of IP-TFA is 0% in Japan, again supporting the observed differences in biomarker levels.…”

“…Table 3 shows plasma levels of fatty acids including ω fatty acids and trans fatty acids. Compared with old men in USA, plasma levels of DHA and EPA were higher in Japanese men and plasma levels of elaidic and linoelaidic acids were higher in Old mane in USA [8]. Table 4 shows that there were no correlations between foods intakes and plasma levels of trans fatty acids and that only preference drinks such as tea and coffee had significant correlations with plasma levels of palmitoelaidic acid and linoelaidic acid.…”

“…We have reported that plasma levels of the major industrially-produced trans fatty acids (IP-TFAs; elaidic and linoelaidic acids) were far higher in American men, and levels of the potentially cardioprotective, primarily ruminant-derived trans fatty acid palmitoelaidic acid (POA) were higher in Japanese. [8].…”

Comparison of plasma levels of different species of trans fatty acids in Japanese male patients with acute coronary syndrome versus healthy men

“…In recent studies comparing TFA levels between US and Japan, both we and others have observed much lower levels in Japan, consistent with lower CHD rates [18.19]. Our recent study with Japanese and American older men (> age 50) showed markedly lower levels of elaidic and linoelaidic acids (IP-TFA) and significantly higher levels of palmitelaidic acids (R-TFA), compared with American men [18]. The Hawaii-Los Angeles-Hiroshima Study reported that serum elaidic acid concentrations in the native Japanese living in Hiroshima were significantly lower than those in the Japanese-Americans living in Los Angeles [19].…”

Correlation of Various Foods Intakes and Plasma Levels of Omega Fatty Acids in Healthy Japanese Old Men

“…Dihomo-g-linolenic acid is converted to arachidonic acid. We have indicated that plasma levels of AA and dihomo-g-linolenic acid (DHGL) were lower in Japanese than American [23]. Since oils and meat contain AA (Figure 3), we thought that American people intake more meat and oils than Japanese resulting in increased plasma levels of AA and dihomo-g-linolenic acid.…”