Acute effect of dietary stanyl ester dose on post-absorptive α-tocopherol, β-carotene, retinol and retinyl palmitate concentrations

Abstract

Stanyl esters dissolved in margarine inhibit cholesterol absorption, lower sterol absorption in general, and lower serum total cholesterol, LDL-cholesterol and plant sterol levels. To find out whether stanyl esters inhibit absorption of fat-soluble vitamins and b-carotene in acute experiments, we performed two fat-tolerance tests fortified with vitamins (retinol 0´9± 3´7 mg, a-tocopherol 70±581 mg), b-carotene (25±150 mg) and squalene (0´5 g) with and without 1 g of stanyl ester added to the test meal in ten healthy men. The concentrations or areas under the curves (AUC) of cholesterol, triacylglycerols, squalene and a-tocopherol, b-carotene and retinyl palmitate showed typical postprandial changes in serum, chylomicrons, VLDL and VLDL infranatant (intermediate-density lipoproteins, LDL and HDL) over 24 h after the test meal without stanyl esters, and they were not affected by the addition of stanyl esters. The postabsorptive serum campesterol concentration and campesterol : cholesterol were significantly lowered at 6±9 h by stanyl ester supplementation, reflecting reduced sterol absorption efficiency. Changes in vitamin and b-carotene AUC did not correlate with the given doses. In conclusion, the present study shows that stanyl esters dissolved in margarine do not detectably interfere in a short-term study with the absorption of a-tocopherol, b-carotene or retinol measured by a 24 h oral fat-load test.

Phytosterols: lack of cytotoxicity but interference with β-carotene uptake in Caco-2 cells in culture

“…Some studies have suggested that phytosterol stanyl esters do not interfere with the short-term absorption of a-tocopherol or b-carotene (Hallkainen et al 1999, Relas et al 2001.…”

Serum and lipoprotein sitostanol and non-cholesterol sterols after an acute dose of plant stanol ester on its long-term consumption

“…After consumption of 3 g of plant stanols as esters for 2 weeks, the postprandial lipoproteins were reduced even though serum cholesterol level was inconsistently decreased during this short treatment period [7]. An acute plant stanol ester supplementation with 1 g of plant stanols added to the test meal in subjects with no previous plant stanol consumption had no effect on postprandial lipoproteins [8]. However, serum campesterol-to-cholesterol ratio was reduced after 6 h postprandially suggesting inhibited absorption of campesterol from its intestinal pool already with one small dose.…”

“…However, less is known about the effect of phytosterol consumption on postprandial lipoproteins, markers of atherosclerotic burden, and on non-cholesterol sterols, markers of cholesterol metabolism. There are two earlier studies dealing with postprandial effects of chronic or acute use of plant stanols [7,8]. After consumption of 3 g of plant stanols as esters for 2 weeks, the postprandial lipoproteins were reduced even though serum cholesterol level was inconsistently decreased during this short treatment period [7].…”

Postprandial plasma oxyphytosterol concentrations after consumption of plant sterol or stanol enriched mixed meals in healthy subjects

“…This might explain why most studies so far did not report increased postprandial plant sterol concentrations after plant sterol consumption. In two studies, blood sampling may have been too late after consumption of the meals [25,26], while in another 4-h study a second meal was not included [27]. Plasma 7b-OH-phytosterol concentrations demonstrated a comparable second meal response, since peak concentrations were seen two hours after consumption of the second meal.…”