Natural compounds found in soy and other plants may significantly reduce the risk of breast cancer recurrence and death.
Researchers reviewed 22 published studies that looked at the impact of eating isoflavones, which are found in soybeans, and lignans (Pronounced: lig-nans), which are found in a variety of plants, vegetables, nuts, seeds and green tea.
Consumption of soy isoflavones was linked to a 26% lower risk of breast cancer recurrence, according to the results.
The largest benefit was seen at 60 milligrams per day, or about two to three servings.
The effect of soy isoflavones on breast cancer mortality was found to be smaller and not statistically significant.
The researchers also looked at the effect of lignans on the disease.
Lignans produce a compound called enterolactone, which was found to reduce the risk of death from breast cancer by 28% and death from any cause by 31% overall and 35% in post-menopausal women.
The lead author says, “These findings were graded probable, which means there is strong research showing that they contributed to the results we are seeing.”
The senior author says the studies in their analysis were conducted on women who received medical treatment and/or surgery for breast cancer and stresses, “…These foods and phytonutrients should not be considered as alternatives to treatment.”
She says more studies are needed to determine the most effective doses of these compounds and whether eating them after breast cancer diagnosis protects as well as eating them over a lifetime.
