Comparison of intestinal absorption of cholesterol with different plant sterols in man*

Abstract

Intestinal absorption of cholesterol, campesterol, campestanol, stigmasterol and sitosterol were measured in 10 healthy subjects by an intestinal perfusion technique over a 50 cm segment of the upper jejunum using sitostanol as non-absorbable marker. Cholesterol absorption was highest and averaged 33%., whereas the absorption rate of sitosterol averaged 4.2% and of stigmasterol 4.8%. Higher absorption rates were found for campesterol (9.6%). Campestanol, the 5 alpha saturated derivative of campesterol, showed the highest absorption rate (12.5%) of all plant sterols. A positive correlation between the absorption rate of cholesterol and campesterol was established. In addition, there was a negative correlation between the ratio of sitosterol to cholesterol and the mass of cholesterol absorption. These results are in agreement with previous observations in animal studies, namely, that increasing the length of the side-chain of cholesterol decreases the absorbability of the sterol. Surprisingly, campestanol, the 5 alpha saturated derivate of campesterol, was shown to have higher absorbability compared with its unsaturated compound. This finding is in contrast to previous assumptions, that hydrogenisation of the nucleus double bond of a sterol causes a decrease of absorbability, as has been demonstrated for cholesterol/cholestanol and sitosterol/sitostanol.

Will recommended changes in fat and fibre intake affect cholesterol absorption and sterol excretion? An ileostomy study

“…A similar, although weaker correlation has been reported by Miettinen, who found a coef®-cient of correlation of 7 0.25 between dietary plant sterols, determined as faecal plant sterols, and fractional cholesterol absorption in 63 middle-aged men on self-selected diets (Miettinen & Kesaniemi, 1989). This is also in agreement with human perfusion studies where there was a similar negative correlation between fractional cholesterol absorption and the ratio of sitosterol to cholesterol presented in the perfusion tube (Heinemann et al, 1993). There was also a negative correlation between cholesterol absorption and dietary ®bre excretion, although somewhat weaker than for plant sterol excretion (r Pearson 7 0.64).…”

“…Plant sterol excretion will re¯ect dietary intake, as the absorption of b-sitosterol, the major component of plant sterols, is very poor (Salen et al, 1970;Heinemann et al, 1993). A similar, although weaker correlation has been reported by Miettinen, who found a coef®-cient of correlation of 7 0.25 between dietary plant sterols, determined as faecal plant sterols, and fractional cholesterol absorption in 63 middle-aged men on self-selected diets (Miettinen & Kesaniemi, 1989).…”

Solubilization of phytosterols in diacylglycerol versus triacylglycerol improves the serum cholesterol-lowering effect

“…PS have been suggested to reduce serum cholesterol concentrations by competitively blocking cholesterol absorption from the intestinal lumen (Heinemann et al, 1986(Heinemann et al, , 1993, displacing cholesterol from bile salt micelles (Child & Kukis, 1986), increasing bile salt excretion (Salen et al, 1970), or hindering the cholesterol esteri®cation rate in the intestinal mucosa (Child & Kukis, 1983;Ikeda & Sugano, 1983). Ikeda et al also showed that the only site of action was during binding of sterols to micelles (Ikeda et al, 1988).…”

Comparison of the effects of plant sterol ester and plant stanol ester-enriched margarines in lowering serum cholesterol concentrations in hypercholesterolaemic subjects on a low-fat diet

“…Plant sterols are absorbed from 5% (sitosterol) to 15% (campesterol) (Heinemann et al, 1993;Salen et al, 1970). Furthermore, plant sterols and stanols may interfere with the absorption of carotenoids, as indicated by reduced serum carotenoid concentrations (Gylling et al, 1999b;Hallikainen et al, , 2000Hendriks et al, 1999;Weststrate & Meijer, 1998).…”