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Review Shows Two Ways Phytosterols Maintain Cell Health

By Greg Arnold, DC, CSCS, August 3, 2009, abstracted from “Anticancer effects of phytosterols” in the July 2009 issue of the European Journal of Clinical Nutrition

Phytosterols are plant antioxidants found in high amounts in legumes such as sesame, chickpeas, lentils and peas, cereal grains such as wheat, corn, millet, rye and barley (1), and nuts such as pecans, pine, pistachio nuts, peanuts, cashew nuts and almonds (2). It is believed phytosterols are the reason nuts are so healthful. For example, 50–100 grams (1.5–3.5 servings) of nuts per day five times per week “may significantly decrease” both total cholesterol and LDL cholesterol (3), decrease the risk of type 2 diabetes (4), and “may be one of the most acceptable lifestyle interventions for the prevention of coronary heart disease” (5).

Phytosterols have also been shown to decrease the risk of certain types of cancer (6) and enhance immune function (7), even in low amounts (8). Now a new study (9) has found how phytosterols may help keep our cells healthy.

Previous research has shown that free radicals increase cancer risk by damaging cells (10), Building on these findings, researchers conducted a review of existing research and found that phytosterols help maintain cell health by two separate mechanisms:

1. Cell Division: Exposing leukemia cells to a phytosterol called beta-sitosterol in amounts of 6.1 and 8 grams reduced their dividing by 37% and 33%, respectively (11) ,while 6.5 grams and 3.25 grams of beta-sitosterol reduced both breast (12) and prostate cancer (13) cell division by 9% and 50%, respectively.

2. Natural cell death: A process of “programmed cell death” called apoptosis is crucial to keeping normal cells from becoming cancerous (13). Phytosterols help maintain apoptosis in cells by increasing levels of an enzyme called capsase-3 by as much as 300% (11). Capsase-3 decreases the activity of a protein called bcl-2, which decreases apoptosis and causes normal cells to become cancerous (14).

For the researchers, “This combined evidence strongly supports an [anti-cancer] action of phytosterols and hence advocates their dietary inclusion as an important strategy in prevention and treatment of cancer.”

Greg Arnold is a Chiropractic Physician practicing in Danville, CA. You can contact Dr. Arnold directly by emailing him at mailto:PitchingDoc@msn.com or visiting his web site at www.CompleteChiropracticHealthcare.com


1. Ryan E, Galvin K, O'Connor TP, Maguire AR, O'Brien NM (2007). Phytosterol, squalene, tocopherol content and fatty acid profile of selected seeds, grains, and legumes. Plant Foods Hum Nutr 62, 85–91
2. Ryan E, Galvin K, O'Connor TP, Maguire AR, O'Brien NM (2006). Fatty acid profile, tocopherol, squalene and phytosterol content of brazil, pecan, pine, pistachio and cashew nuts. Int J Food Sci Nutr 57, 219–228
3. Jerling JC. A Systematic Review of the Effects of Nuts on Blood Lipid Profiles in Humans. J. Nutr. 135:2082-2089
4. Jiang R. Nut and peanut butter consumption and risk of type 2 diabetes in women. JAMA. 2002 Nov 27;288(20):2554-60
5. Strahan TM. Nuts for cardiovascular protection. Asia Pac J Clin Nutr. 2004;13(Suppl):S33
6. Awad, A. B.; Fink, C. S. Phytosterols as anticancer dietary components: evidence and mechanism of action. J. Nutr. 2000, 130, 2127-2130.
7. Bouic, P. J. The role of phytosterols and phytosterolins in immune modulation: a review of the past 10 years. Curr. Opin. Clin. Nutr. Metab. Care 2001, 4, 471-475
8. Kris-Etherton, P. M.; Yu-Poth, S.; Sabaté, J.; Ratcliffe, H. E.; Zhao, G.; Etherton, T. D. Nuts and their bioactive constituents: effects on serum lipids and other factors that affect disease risk. Am. J. Clin. Nutr. 1999, 70, 504S-511S
9. Woyengo TA. Anticancer effects of phytosterols. European Journal of Clinical Nutrition (2009) 63, 813–820; doi:10.1038/ejcn.2009.29; published online 3 June 2009
10. Vivancos M, Moreno JJ (2005). -Sitosterol modulates antioxidant enzyme response in RAW 264 7 macrophages. Free Radic Biol Med 39, 91–97.
11. Park C, Moon D, Rhu C, Choi BT, Lee WH, Kim G et al. (2007). -Sitosterol induces anti-proliferation and apoptosis in human leukemic U937 cells through activation of caspase-3 and induction of Bax/Bcl-2 ratio. Biol Pharm Bull 30, 1317–1323
12. Awad AB, Chinnam M, Fink CS, Bradford PG (2007). -Sitosterol activates Fas signaling in human breast cancer cells. Phytomedicine 14, 747–754.
13. Awad AB, Burr AT, Fink CS (2005). Effect of resveratrol and -sitosterol in combination on reactive oxygen species and prostaglandin release by PC-3 cells. Prostaglandins Leukot Essent Fatty Acids 72, 219–226.
14. Moon DO, Kim MO, Choi YH, Kim GY (2008). beta-Sitosterol induces G2/M arrest, endoreduplication, and apoptosis through the Bcl-2 and PI3K/Akt signaling pathways. Cancer Lett 264, 181–191
15. Prescott SM (2000). Is cyclooxygenase-2 the alpha and the omega in cancer? J Clin Invest 105, 1511–1513
16. Choi J, Lee E, Lee H, Kim K, Ahn K, Shim B et al. (2007). Identification of campesterol from Chrysanthemum coronarium L and its antiangiogenic activities. Phytother Res 21, 954–959.