The Merits of Flaxseed

August 1, 2007

Flaxseed, an edible seed that is rich in omega-3 fatty acids and fiber-related compounds known as lignans, is effective in halting prostate tumor growth, according to a study led by Duke Medical Center researchers. The small, dark brown seed, which is similar to a sesame seed and is available in grocery stores, may be able to interrupt the chain of events that leads cells to divide irregularly and become cancerous.

Previous studies showed a correlation between flaxseed in the diet and slowed tumor growth, but "the participants in those studies had taken flaxseed in conjunction with a low-fat diet," says Wendy Demark-Wahnefried, a researcher in Duke's School of Nursing and lead investigator of the multi-site study. "For this study, we demonstrated that it is flaxseed that primarily offers the protective benefit."

In the study, the researchers examined the effects of flaxseed supplements on men who were scheduled to undergo prostatectomy-surgery to treat prostate cancer. The men took thirty grams of ground flaxseed daily for an average of thirty days before surgery.

Once the men's tumors were removed, the researchers looked at tumor cells under a microscope and were able to determine how quickly the cancer cells had multiplied. Men taking flaxseed, either alone or in conjunction with a low-fat diet, were compared with 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. Men in both of the flaxseed groups had the slowest rate of tumor growth.

Flaxseed is thought to play a part in halting the cellular activity that leads to the spread of cancer. As a source of omega-3 fatty acids, flaxseed could alter how cancer cells lump together or cling to other body cells, both factors in how fast cancer cells proliferate, Demark-Wahnefried says.

The results of the study were presented at the annual meeting of the American Society of Clinical Oncology in June.