Abstract
Trans fatty acids (TFA) are positional isomers of cis fatty acids. TFA are mainly produced by partial hydrogenation of unsaturated fatty acids and widely found in a variety of foods, including margarines, shortening and frying oil. A small amount of TFA is also found in ruminant fats and milk. The amount of TFA intake in Western Europe and North America probably ranges from 5 to 15 g / day. Epidemiological studies have shown that the excessive consumption of TFA raises LDL-cholesterol and lowers HDL-cholesterol in humans. Therefore, high intakes of TFA are thought to be a risk factor of coronary heart disease. On the basis of the scientific evidence, the U. S. FDA required labeling of the TFA content in conventional food and dietary supplement on January 1, 2006. TFA intake in Japan is estimated to be approximately 0.7 to 1.3 g / day, the amount is markedly lower than that in western countries. Although the low TFA intake in Japan is not thought to be an important issue at present, we should pay attention to an excessive intake of TFA in the future.
