Chasteberry, Vitex agnus castus, is a medicinal herb with estrogenic activity that is used to treat premenstrual syndrome and other female reproductive and general health conditions, including infertility, perimenopausal symptoms, endometriosis, acne and Parkinson's disease. Chasteberry fruit, leaves and seeds all contain active components, though manufacturers produce most modern supplements from the fruit. Consult your doctor for guidance and supervision in using chasteberry.
Chasteberry shows estrogen-like effects in test tube studies, but its effectiveness in humans remains unproven and its estrogenic compounds are commonly available in other foods, says Holly Phaneuf, Ph.D., author of the book "Herbs Demystified: A Scientist Explains How the Most Common Herbal Remedies Really Work." Linoleic acid, which is found in many foods, including corn, safflower and soy bean oils, is one of chasteberry's estrogenic compounds. Apigenin, another estrogenic compound in chasteberry, is also prevalent in plant foods. Other active compounds in chasteberry are yet to be identified.
A study in the November 2010 issue of the "Journal of Sexual Medicine" listed chasteberry as potentially useful for conditions associated with low estrogen levels, such as menopause and some forms of infertility. The review of previously published research notes that most studies on herbs for treatment of female sexual dysfunction focus on those with potential for treating menopausal hot flashes and note that chasteberry may be useful for a variety of conditions. Other multi-function herbs listed with chasteberry include black cohosh and red clover.
Chasteberry increases progesterone but not estrogen levels, according to the November 2008 issue of the "American Journal of Primatology." The study evaluated primates that eat chasteberry as part of their diet and found that a dramatic rise in progesterone levels occurs during a six-week period each year when chasteberry consumption is high. Researchers note that this evidence is some of the first to show dietary phytochemicals influencing hormone levels. Further research is needed to determine whether chasteberry consumption influences reproductive function.
Your risk for estrogen-related cancers may increase with use of chasteberry, according to a study published in the January 2004 issue of the journal "Phytomedicine." The tissue culture study of breast and uterine cancer cells exposed to chasteberry showed that the herb attached to estrogen receptors on the cancer-cell surfaces, activating them and promoting their growth and reproduction. The essential fatty acid linoleic acid was responsible for the estrogenic effects. However, chasteberry did not promote a form of estrogen-related activity in the liver that normally increases levels of certain liver enzymes, indicating potential safety of the herb for liver function.