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
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