Effects of dietary phytosterols on cholesterol metabolism and atherosclerosis: clinical and experimental evidence

  • Mohammed H Moghadasian
    Healthy Heart Program and Department of Pathology and Laboratory Medicine, St. Paul’s Hospital and University of British Columbia, Vancouver, BC, Canada
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  • Jiri J Frohlich
    Requests for reprints should be addressed to Jiri J. Frohlich, MD, Department of Pathology and Laboratory Medicine, University of British Columbia, St. Paul’s Hospital, 180-1081 Burrard Street, Vancouver, BC, Canada V6Z 1Y6
    Healthy Heart Program and Department of Pathology and Laboratory Medicine, St. Paul’s Hospital and University of British Columbia, Vancouver, BC, Canada
    Search for articles by this author


      Although plant sterols (phytosterols) and cholesterol have similar chemical structures, they differ markedly in their synthesis, intestinal absorption, and metabolic fate. Phytosterols inhibit intestinal cholesterol absorption, thereby lowering plasma total and low-density lipoprotein (LDL) cholesterol levels. In 16 recently published human studies that used phytosterols to reduce plasma cholesterol levels in a total of 590 subjects, phytosterol therapy was accompanied by an average 10% reduction in total cholesterol and 13% reduction in LDL cholesterol levels. Phytosterols may also affect other aspects of cholesterol metabolism that contribute to their antiatherogenic properties, and may interfere with steroid hormone synthesis. The clinical and biochemical features of hereditary sitosterolemia, as well as its treatment, are reviewed, and the effects of cholestyramine treatment in 12 sitosterolemic subjects are summarized. Finally, new ideas for future research into the role of phytosterols in health and disease are discussed.
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