How does Soy work?

Soy contains "isoflavones" which are changed in the body to "phytoestrogens" which are similar to the hormone estrogen.

Are there safety concerns?

Consuming soy foods such as soy protein is safe. Taking soy dietary supplements also seems to be safe for most people when used short-term. It can cause some mild side effects such as constipation, bloating, and nausea. It can also cause allergic reactions involving rash and itching in some people. Long-term use of high doses of soy dietary supplements might not be safe. There is concern that taking high doses might cause abnormal tissue growth in the uterus.

Do not take soy in amounts greater than what is normally found in foods if:
  • You are pregnant or breast-feeding.
  • You have breast cancer or if breast cancer runs in your family.
  • You have endometrial cancer.
  • You have kidney disease.
  • You have a risk of urinary bladder cancer.
Do not use soy in children without medical supervision.

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