Key Findings:
This older review indicates that animal studies show that dietary intake of flaxseed and flaxseed oil can inhibit breast cancer progression. Flaxseed lignans effects on breast cancer growth may be concentration dependent: stimulation at lower concentrations but inhibition at higher concentrations. The implication that flaxseed may have similar anti-tumour effects on breast cancer as tamoxifen (as seen in some research) means that it may have similar potential in reducing the efficacy of cytotoxic chemotherapy. The interactions of the various components of flaxseed, when taken as whole food, on the kinetics and dynamics of phyto-estrogens on breast tumour growth is under investigation.
ABSTRACT:
The use of flaxseed (linseed) to combat breast cancer has attracted increased attention since the preliminary results of a clinical study were presented in the San Antonio Breast Cancer Symposium in December 2000. One of the most often quoted implications of the study was that the anti-tumour effect of flaxseed muffin may be comparable to that of tamoxifen. However, flaxseed also contains secoisolariciresinol diglycoside (SDG), which is converted by the gut bacteria into the oestrogenic lignans, enterodiol and enterolactone. Given that other plant-derived oestrogenic substances (phyto-oestrogens) can stimulate breast cancer growth under certain circusmtances, there are concerns regarding the safety of flaxseed. The following review will look at the existing data to help clarify some of these issues. (Author’s Abstract)
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