According to a study at Duke University Medical Center flaxseed stunts the growth of prostate tumors.

Flaxseeds, rich in omega 3-fatty acids and lignans (a fiber-related compound) has demonstrated the ability to halt prostate tumor growth. The sesame seed like flaxseed seems to be able to interrupt the chain of events that leads cells to divide irregularly and become cancerous.

Wendy Demark-Wahnefried, Ph.D., a researcher in Duke’s School of Nursing and lead investigator on the study said, “Our previous studies in animals and in humans had shown a correlation between flaxseed supplementation and slowed tumor growth, but the participants in those studies had taken flaxseed in conjunction with a low-fat diet. For this study, we demonstrated that it is flaxseed that primarily offers the protective benefit.”

The study results were presented on Saturday, June 2, during a news briefing at the annual meeting of the American Society of Clinical Oncology, in Chicago. The multisite study, which was funded by the National Institutes of Health, also involved researchers at the University of Michigan and the University of North Carolina at Chapel Hill.

The researchers in this study examined the effects of flaxseed supplementation on men who were scheduled to undergo prostatectomy. The research protocol called for each subject to take 30 grams of flaxseed daily for an average of 30 days prior to their surgery. Post-surgery the the tumor cells were examined with the goal of determining how quickly the prostate cancer cells had multiplied.

Men were given the flaxseed both alone or in conjunction with a low-fat diet. This research arm was then compared to men assigned to just a low fat diet, as well as to men in a control group, who did not alter or supplement their daily diet.

Those men in both of the flaxseed groups had a significantly slower rate of tumor growth. Each arm of the study consisted of about 40 subjects, or about 180 men.

Flaxseed was always given to all the subjects in its ground form since its outer coat is indigestible. Participants were allowed to mix the flaxseed in drinks or sprinkle it on food, such as yogurt.

“The results clearly demonstrate that the men who took just flaxseed as well as those who took flaxseed combined with a low-fat diet did better then the men who did not consume flaxseed.

Why flaxseed leads to prostate cancer cell growth control is not clear. According to the study authors theories include that it could be that as a source of omega-3 fatty acids, flaxseed can alter how cancer cells lump together or cling to other body cells thus controlling how fast cancer cells proliferate. The researchers also suspect that lignans may have antiangiogenic properties, meaning they are able to choke off a tumor’s blood supply, stunting its growth.

The researchers hope to next test the effectiveness of flaxseed supplementation in patients with recurrent prostate cancer, and ultimately to study its role as a preventative agent. However, in the mean time those of us with recurrent and advanced prostate cancer should consider supplementing flaxseeds now, even without the follow-up study. One note of caution, there is evidence that flaxseed oil can actually have the reverse effect and “fuel” prostate cancer.

Joel T Nowak MA, MSW