Abstract
1. The impact of trans fatty acids on coronary heart disease (CHD) is not striking, if any, in epidemiological studies, and the difference in the effects on plasma lipid profiles of trans fatty acids and animal fats is marginal.
2. Partially-hydrogenated oils, as well as some other common vegetable oils, contain minor components (anti-nutritional factors) other than fatty acids, shorten the survival of stroke-prone SHR (SHRSP) rats unusually and some of them exhibit endocrine-disturbing activity. The dose that causes such effects is not extremely high, and the amounts of current Japanese intake do not appear to be in a safe range.
3. Dihydro-vitamin K1 produced by hydrogenation of vegetable oils is pointed out as one of such factors. Our interpretation is that it serves as an anti-nutritional factor to suppress vitamin K-dependent protein synthesis and stimulate the onset of stroke.
4. Several other common vegetable oils exhibit tumor-promoting activities, which cannot be accounted for by their fatty acid compositions, and further research on their safety is required from broader aspects.
5. Most vegetable oils consumed in Japan contain relatively large amounts of linoleic acid and/or anti-nutritional factors, hence are not helpful for the promotion of health. Animal fats are relatively safer than those vegetable oils and hydrogenated oils with anti-nutritional activities.
