Retinol, vitamin D, carotenes and alpha-tocopherol in serum of a moderately hypercholesterolemic population consuming sitostanol ester margarine

We have shown earlier that sitostanol ester margarine lowers serum choleste rol by inhibiting cholesterol absorption so that, theoretically, there coul d be interference with the absorption of fat-soluble vitamins. Accordingly, we investigated whether sitostanol ester margarine affects the serum level s of vitamin D, retinol, alpha-tocopherol and alpha- and beta-carotenes dur ing 1-year treatment in 102 subjects and 49 controls with moderate hypercho lesterolemia. The vitamins were assayed at baseline on home diet, on margar ine alone, after 1 year's consumption of sitostanol ester margarine and aft er an additional 2 months on home diet. In the sitostanol group, serum plan t sterols, indicators of cholesterol absorption efficiency, were reduced up to - 38% in relation to controls from home diet (P < 0.01) indicating that cholesterol absorption was markedly reduced. Vitamin D and retinol concent rations and the ratio of alpha-tocopherol to cholesterol were unchanged by sitostanol ester. Serum beta-carotenes and alpha-carotene concentration but not proportion were reduced in the sitostanol group from baseline and in r elation to controls (P < 0.01). Retinol and vitamin D were unassociated wit h serum cholesterol, plant sterols or other vitamins, whereas alpha-tocophe rol and carotenes were significantly associated with serum plant sterols su ggesting that the higher cholesterol absorption efficiency, the higher the alpha-tocopherol and carotene levels in serum. We conclude that sitostanol ester did not affect vitamin D and retinol concentrations and alpha-tocophe rol/cholesterol proportion, but reduced serum beta-carotene levels, alpha-T ocopherol and carotenes, but not vitamin D and retinol, were related to ser um cholesterol and cholesterol absorption. (C) 1999 Elsevier Science Irelan d Ltd. All rights reserved.