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Top Anti-Oestrogen Foods

Posted by Manuela Boyle on 19 November 2020

Oestrogen feeds and fuels 80 percent of all breast cancers via oestrogen binding to an estrogen receptor on the cell's surface. The goal of hormone therapy is to reduce oestrogen levels in the body with either an aromatase inhibitor or a hormonal blocker like tamoxifen. Research has shown that certain foods also can help decrease oestrogen. For example, whole foods made from soybeans contain phyto (plant) oestrogen compounds called isoflavones. When consumed in their whole food form,  isoflavones behave as a very weak form of oestrogen on " alpha" oestrogen receptors in the body; so instead of stimulating the growth of cancer, when isoflavones bind to alpha oestrogen receptors, they help block the ability of oestrogen to bind and send signals to the cancer cell to multiply and divide. When isoflavones bind to "beta" oestrogen receptors, guess what happens? They act as strong anti-oestrogens by shutting alpha down, and by going into fat cells to shut the oestrogen-making aromatase enzyme down, thereby lowering oestrogen levels. Make sure to read our detailed post on soy where we set the record straight on many of these misconceptions.

The research on soy foods and breast cancer has found that eating 1 or 2 half-cup servings each day can be protective. Choose organic, unprocessed tofu, tempeh, natto, edamame, or unsweetened soy tamari or miso paste as a seasoning when making soups or sautéing vegetables.

Consistent findings from population studies indicate no increased risk for breast cancer survivors who consume soyfoods. In fact, limited evidence shows the potential for greater overall survival and perhaps decreased recurrence, among women a year or more after diagnosis who include moderate amounts of soy.

PMID: 27161216 DOI: 10.1159/000444735


Author: Manuela Boyle
Tags: News Breast Cancer


  • The Institute for Functional Medicine
  • Society for Integrative Oncology
  • American Society of Clinical Oncology
  • Australasian Integrative Medicine Association
  • Naturopaths and Herbalists Association of Australia
  • British Naturopathic Association

Disclaimer: Manuela Boyle is not a registered medical practitioner or specialist medical oncologist. Manuela Boyle is a general health service provider who is not legally required to be registered under National Health Practitioner regulation law. She practises under the national Code of Conduct that sets standards to general health service providers who are not regulated by the Australian Health Practitioner Regulation Agency.

Manuela Boyle is an accredited member of the following professional organisations:
NHAA (Naturopaths & Herbalists Association of Australia), SIO (Society of Integrative Oncology) USA, AIMA (Australasian Integrative Medical Association), IFM (Institute of Functional Medicine) USA