Phytosterols early studies

During the early 1950s, it was reported that phytosterols lower serum cholesterol (173-175). This effect was appreciated as a possible protection strategy against car-divascular disease risk after the results of several convincing animal and human studies (176-184). Studies have shown that a daily intake of 2-g phytosterol or phytostanol causes 40-50% reduction in the dietary cholesterol absorption, 6-10% reduction in total serum cholesterol, and 8-14% reduction in the semm low-density lipoprotein cholesterol (37, 185-187). 

The cholesterol-lowering properties of phytosterols were first demonstrated in the early 1950s by Peterson (1951), who fed cholesterol and plant sterols to chicks and found that soy sterols inhibited the increase in cholesterol concentration otherwise induced by cholesterol feeding. Shortly afterwards, Poliak (1953) showed the same effect in humans, to whom he administered 5-10 g of crude sitosterol daily for up to 8 months. In similar studies in rabbits, he observed that sitosterol was poorly absorbed and that, if present in excess, it blocked the absorption of cholesterol and prevented atherosclerosis. Poor absorption and lack of any endogenous synthesis of sitosterol in humans were subsequently demonstrated by Salen et al. (1970). 

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