This food and dietary supplement may reduce prostate cancer spread, improve survival in breast cancer, and lower the risk of several cancers.
Flaxseed at a glance
Flaxseed contains many components beneficial to health: lignan precursors, fiber, magnesium, thiamin, and the omega-3 fatty acid alpha-linolenic acid (ALA). The lignan precursor secoisolariciresinol diglycoside (SDG) is found in high concentrations in flaxseed but also in lesser amounts in several other plant foods.
Flax lignans weakly alter the effects of your natural estrogen but do not have a consistent pro-estrogen effect, and they may even have an anti-estrogen effect. Flaxseed may reduce the spread of prostate cancer and improve survival in breast cancer. It may also lower risk of breast, colon, or lung cancers.
Research sometimes shows different effects from whole flaxseed and flaxseed supplements. For example, whole (dietary) flax and supplements have different Impacts on blood sugar control and insulin sensitivity. As with many other supplements made from foods, the supplements may not have all the components of the whole food that combine to contribute to the benefits seen with whole flaxseed.
Bacteria in your colon metabolize the precursor into enterolactone and enterodiol. These substances are called “lignans” in some studies, but “lignan metabolites” in other studies. For simplicity, we’ll use the term “lignans” to refer to both precursors and metabolites in general.
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