Flaxseed for Cancer Risk Reduction

Research suggests a mixed and inconclusive picture when it comes to flaxseed and cancer risk reduction, particularly for prostate cancer. A 2010 review examining preclinical studies, clinical intervention trials, and epidemiological data found that while some early research using flaxseed and surrogate biological markers showed suggestive findings, no consistent reduction in prostate cancer risk has been demonstrated at the population level. Studies indicate that the amounts of lignans — the plant compounds in flaxseed thought to be responsible for any potential effect — typically consumed through an ordinary diet may be too low to produce a meaningful preventive impact, and researchers have yet to establish what blood or tissue concentrations would even be necessary. The reviewers called for further clinical trials using purified lignan compounds before any firm conclusions can be drawn, underscoring that the current body of evidence does not yet support a reliable health claim.