There is no evidence that taking flaxseed can lower your risk of prostate cancer. There have been few studies on this subject, and the evidence is mixed as to whether flaxseed has any effect on the prostate.
In one study involving men diagnosed with prostate cancer, those who took a flaxseed supplement and followed a low-fat diet saw their prostate-specific antigen (PSA) levels decline. PSA can be a measure of how fast prostate cancer is spreading.
Other preliminary studies report that a low-fat diet supplemented with flaxseed reduced PSA levels in men with enlarged prostate glands (benign prostatic hyperplasia) and in those with prostate cancer. However, those results may have been due to a reduction in dietary fats.
Other studies have shown either no positive effect or a negative effect of flaxseed — and the alpha-linolenic acid contained in flaxseed — on prostate health.
Overall, it remains unclear whether flaxseed or flaxseed oil has a role in the prevention or treatment of prostate cancer. Controlled clinical trials may help determine whether or not it's useful in the long term.
Dec. 11, 2014
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- Demark-Wahnefried W, et al. Flaxseed supplementation (not dietary fat restriction) reduces prostate cancer proliferation rates in men presurgery. Cancer Epidemiolgy, Biomarkers and Prevention. 2008;12:3577.
- Flaxseed. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Nov. 14, 2014.
- Demark-Wahnefried W, et al. Pilot study to explore effects of low-fat, flaxseed supplemented diet on proliferation of benign prostatic epithelium and prostate-specific antigen. Urology. 2004;63:900.
- Leitzmann MF, et al. Dietary intake of n-3 and n-6 fatty acids and the risk of prostate cancer. American Journal of Clinical Nutrition. 2004;80:204.
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- Heymach JV, et al. Effect of low-fat diets on plasma levels of NF-(kappa)B-regulated inflammatory cytokines and angiongenic factors in men with prostate cancer. Cancer Prevention Research. 2011;4:1590.