Phytoestrogens, sometimes called “dietary estrogens”, are a diverse group of naturally occurring non steroidal plant compounds that, because of their structural similarity with estradiol, have the ability to cause estrogenic/and antiestrogenic effects.
- Phytoestrogens have anti-oxidant activity and are reputed to have the following health benefits:
- Protection against bowel and prostrate cancer
- Mixed protection for breast cancer. As outlined further on in this post, the protection phytoestrogens provide for breast cancer depend on the type of cancer you have
- Reduction in the risk of cardiovascular disease
- Possible protection against osteoporosis including maintenance of bone density post-menopause
- Reduction in menopausal symptoms
Phytoestrogens are broken down into:
Flavenoids which are high in soy bean and soy bean products. There are three subtypes of flavenoids
1. Isoflavones, found if soy, red clover and legumes
2. Flavones
3. Coumestans
Lignans, mainly found in nuts and oils seeds such as flaxseed
PLEASE NOTE: While phytoestrogens are considered beneficial for women, women with known breast cancer are generally advised to consider avoiding rich sources of phytoestrogen until more research is performed. While epidemiological studies suggest that phytoestrogens have a protective effect against breast cancer, some laboratory studies show that phytoestrogens could stimulate tumour growth because they stimulate the growth of oestrogen receptors in test tubes. If you have had breast cancer speak with your oncologist for advice.
Phytoestrogens ARE NOT considered nutrients as a lack in the diet does not have an associated deficiency syndrome, and they have not yet been identified as having an essential biological function.
Phytoestrogen levels in foods vary depending on where the food was sourced from, or how it was processed if it is a processed food such as tofu. This list was taken from a Canadian research study.