Estrogen plays a vital role in a woman’s health throughout her lifetime. There comes a time, however, when estrogen may do more harm than good. Only menopause or surgical removal of the ovaries will completely prevent estrogen production, but it is possible to block the effects of estrogen through nutrition. Talk to your doctor or a certified nutritionist before launching a dietary campaign to alter your estrogen levels, especially if you have a chronic condition or take medications.
Fruits and Vegetables
There is a persistent belief that certain fruits and vegetables, such as grapes, berries, broccoli, rutabagas and bok choy, contain active ingredients that serve as natural estrogen blockers. According to Baiba J. Grube and colleagues, authors of a study published in the "Journal of Nutrition" in 2001, various fruits and vegetables contain agents that block estrogen because they are natural aromatase inhibitors, meaning they counter the enzyme responsible for stimulating cell growth in prostate and breast tissue and increasing the risk for cancer. To find out, the scientists tested extracts from green onion, celery, carrot, bell pepper, broccoli, spinach and white button mushroom. The only extracts to demonstrate anti-aromatase activity were celery and mushroom. While celery showed only a mild inhibitory effect, the effect of the mushroom extract on aromatase was much more significant. A subsequent study conducted at the same research facility found similar results, which were published in “Cancer Research” in 2006.
Fatty Acids
The authors of the 2006 study published in “Cancer Research” specifically note that the effect mushrooms have on aromatase is due to ethyl acetate. This compound is primarily composed of unsaturated fatty acids, namely linoleic acid. Using a cell line called MCF-7aro cells because they represent high aromatase activity, the scientists found that mushroom-derived linoleic acid, linolenic acid and conjugated linoleic acid blocked aromatase in the ovaries of hamsters. According to a study published in "Chemical and Pharmaceutical Bulletin" in 2009, other fatty acid derivatives that produce this effect are found in Brassica rapa L., more commonly known as field mustard or turnip greens.
Herbal Supplements
Certain herbs are associated with anti-estrogen properties, such as saw palmetto, red clover, Mexican yam, black cohosh and soy. While some of these herbs may contain chemicals that inhibit aromatase, the more commonly employed estrogen-blocking mechanism is changing how estrogen is used in various tissues and organs. For example, the compound beta-sitosterol, a steroid widely distributed in plants, interacts with progesterone receptors, which results in decreased estrogen production in breast tissue. Plant sterols also decrease estrogen levels by affecting prolactin receptors in the ovaries and androgenic receptors in the prostate.
Safety Considerations
Although a diet rich in a variety of fresh fruits and vegetables provides the nutrients required for optimal health, seek advice from your physician or a certified nutritionist about diet modifications to balance estrogen levels. This applies to supplements as well, including herbal products. Do not attempt to alter estrogen production if you use oral contraceptives or have a history of a hormone-driven cancer, because while some compounds in plants and foods are anti-estrogenic, others increase estrogen production.
References
- "Journal of Nutrition"; White Button Mushroom Phytochemicals Inhibit Aromatase Activity and Breast Cancer Cell Proliferation; B. J. Grube, et al.; December 2001
- “Cancer Research”; Anti-aromatase Activity of Phytochemicals in White Button Mushrooms (Agaricus bisporus); S. Chen, et al.; December 2006
- "Chemical and Pharmaceutical Bulletin"; 5 Alpha-reductase and Aromatase Inhibitory Constituents from Brassica rapa L. Pollen; Y. H. Li, et al.; April 2009
- “Physicians’ Desk Reference for Herbal Medicines”; Thomas Brendler, et al.; 2007
