Q: Is S-equol safe to consume? What evidence of safety exists for S-equol?

The safety of the supplement containing S-equol previously was confirmed by standard animal testing, including a study documenting that S-equol itself, as well as the supplement containing S-equol, did not increase or stimulate the growth of breast cancer cells. Studies involving postmenopausal women who consumed the supplement containing S-equol have not observed any safety problems, including analysis of breast and reproductive tissues and of hormone levels.

Q: What published studies demonstrate the safety of S-equol?

Yes, results from controlled studies demonstrate S-Equol's safety, including research published in Food and Chemical Toxicology and presented at the 2011 American Medical Women's Association annual meeting and the 2010 North American Menopause Society Meeting. For a complete listing of studies conducted to date on S-equol, please see the Research Bibliography

Q: Does S-equol have an adverse impact on breast health or uterine health?

  • The safety of the supplement containing S-equol previously was confirmed by standard animal testing, including a study documenting that S-equol itself, as well as the supplement containing S-equol, did not increase or stimulate the growth of breast cancer cells.
  • Studies involving postmenopausal women who consumed the supplement containing S-equol have not observed any safety problems, including analysis of breast and uterine tissues and of hormone levels.

Q: Is the bacteria used to make this product alive in the product?

No. After fermentation, the soy germ is heated to yield a dry powder with no live bacteria.

Q: Is the bacteria used to make this product safe?

  • Yes. Lactococcus garvieae is the genus to which the strain Lactococcus 20-92 belongs. Lactococcus garvieae, is found in some foods and exists naturally in the large intestines of about 4 in 10 people. Furthermore, during the manufacturing process of S-equol, the soy germ fermented with Lactococcus 20-92 undergoes an extended drying process so that the bacteria are killed, yielding a functional food ingredient containing S-equol with no live bacteria.
  • Diet history: People have consumed Lactococcus garvieae via cheese, including cheese that has been traditionally eaten in Egypt and Italy, with no known reports of adverse health effects.
  • When studying the existence of cytotoxicity of Lactococcus 20-92 strain, red blood cells were not destroyed. Further, when studying the existence of cytotoxicity in relation to cultured cells derived from human digestive organs cells, no cellular damage was seen in relation to any of the cells derived from human digestive organs.
  • Lactococcus 20-92 strain showed no production of verotoxin, a substance produced by bacteria that cause food poisoning. Further, no activity was seen for enzymes involved in tissue damage.
  • Lactococcus 20-92 is responsive to most antibiotics.
  • Lactococcus garvieae in general have been reported to cause illness in fish, but this is not true for the Lactococcus 20-92 strain.

Q: How long can I take this product? Is it safe for long-term use?

S-equol is safe for regular daily use when taken according to label directions.