Estrogen and progesterone are hormones that play a role in reproduction. While men make a small amount of these hormones, they're more commonly thought of as female hormones. Some foods and herbs contain substances similar to estrogen and progesterone, and scientists have discovered a plant that contains progesterone. Plant hormones may offer a safer option for hormone replacement therapy. Synthetic hormones have a number of side effects and risks, such as breast cancer. Before using food or herbs for therapeutic benefit, get permission from your doctor.
English Walnut Leaf Contains Progesterone
In the March 2010 edition of the "Journal of Natural Products," scientists reported, for the first time, that they had discovered the presence of progesterone in a plant. Researchers say that they've found definitive proof that the leaves of the English walnut tree contain progesterone. It was previously believed that only animals produce progesterone, so the finding is significant, write the authors. English walnut leaf, or Juglans regia, extract and dried leaves are available at herbal stores and online. You can make tea using the dried leaves or take a commercial extract preparation. Avoid confusing it with black walnut, or Juglans nigra.
Richest Sources of Plant Estrogens
Soy foods are the richest source of a phytoestrogen class called isoflavones, and eating soy may offer health benefits. Soy consumption in Asian populations is linked to a lower risk of hormone-dependent cancers and bothersome menopausal symptoms, according to Tulane University. In addition, eating less than 90 milligrams a day may protect bone health, according to the Linus Pauling Institute. A 100-gram serving of soy contains about 103 milligrams of phytoestrogens, according to "Phytoestrogens In Functional Foods."
Flaxseeds are the richest source of substances that convert to lignans, another class of phytoestrogens. A 100-gram serving contains about 379 milligrams of phytoestrogens, according to "Phytoestrogens In Functional Foods." Most research has been focused on soy isoflavones, so scientists don't yet know whether lignans have benefits, such as protecting against osteoporosis and hormone-related cancers.
Various other foods contain phytoestrogens, but the amounts are too small to have a therapeutic effect.
Plants with Progesterone-Like Substances
Various foods in your diet contain a progesterone-like substance called kaempferol. According to an article in the April 2011 edition of "Mini Reviews in Medicinal Chemistry," kaempferol has anti-inflammatory, antioxidant and antimicrobial activities. Foods containing kaempferol, write the authors, are linked to a lower risk of cancer and heart disease. Broccoli, cabbage, kale, beans and herbs such as ginkgo biloba, horsetail, linden flower, Moringa oleifera and propolis contain kaempferol. Scientists confirmed the progestrogenic activity of kaempferol in an animal study reported in the July 2014 edition of the "Journal of Steroids and Hormonal Science."
Potential Health Risks
There is substantial confusion and debate surrounding the potential risks of plant hormones. In particular, there is concern regarding whether dietary phytoestrogens are safe for breast-cancer patients or survivors, since the majority of breast cancers are estrogen-dependent.
Short-term dietary supplementation has been shown to cause cell growth in premenopausal women with existing breast tumors, according to a study appearing in the December 2006 edition of the journal of the Society for Endocrinology. However, there is evidence of a protective role in women who do not have breast cancer. More studies are needed, so it's best to err on the side of caution.
Despite rumors to the contrary, there seems to be no evidence that phytoestrogens are harmful to male health. In fact, consuming soy may reduce the risk of prostate cancer, according to the Physicians Committee for Responsible Medicine.
- Science Daily: First Discovery of the Female Sex Hormone Progesterone in a Plant
- Tulane University: Phytoestrogens
- Mini Reviews in Medicinal Chemistry: A Review on the Dietary Flavonoid Kaempferol
- Journal of Steroids and Hormonal Science: Kaempferol Exhibits Progestogenic Effects in Ovariectomized Rats
- Main Line Health: Estrogen, Progesterone, and Menopause
- Linus Pauling Institute: Soy Isoflavones
- Linus Pauling Institute: Lignans
- Society for Endocrinology: Phytoestrogens and Breast Cancer – Promoters or Protectors?
- Physicians Committee for Responsible Medicine: Ask the Expert: Soy