Effect of plant sterol esters on the absorption of dietary cholesterol
Mattson, F.H.; Volpenhein, R.A.; Erickson, B.A.
Journal of Nutrition 107(7): 1139-1146
1977
ISSN/ISBN: 0022-3166 PMID: 874557 Document Number: 120347
Plant sterols were added at the same molar concentration to the dietary fat of rats with thoracic duct cannulae. The oleate esters of beta -sitosterol, campesterol and stigmasterol, individually or in a mixture, were similar in their ability to decrease the absorption of cholesterol from a diet that contained otherwise sterol-free triolein as the only fat. Their effect was equal to that of beta -sitosterol or stigmasterol. beta -Sitosterol esters of short (acetate), medium (decanoate) or long (oleate) chain fatty acids did not differ in their ability to reduce cholesterol absorption. When the dietary fat contained 1% cholesterol, the addition of twice that amount of plant sterol reduced cholesterol absorption by 30%. Increasing the amount of dietary plant sterols further decreased absorption of dietary cholesterol; the response had a log-dose relation. It was suggested that in the intestine, the plant sterol esters are hydrolysed and the resulting free sterol decreases the solubility of cholesterol in the oil and micellar phases with a consequent decrease in cholesterol absorption. There was a similar decrease in the percentage absorption of dietary cholesterol when dietary cholesterol was increased; this was attributed to the same mechanism as that responsible for the effect of the plant sterols. The solubility of the phytosterol esters in fat, in contrast to the limited solubility of their unesterified forms, provides a means for giving effective amounts of these hypocholesterolaemic agents.