Contraindications:
Pregnant or breast-feeding women should only use black cohosh under the care of a knowledgeable practitioner. Taking very large doses (over 10 capsules per day) may cause abdominal pain, nausea, headaches, and dizziness. If you are getting any of these symptoms, lower your dose. Black Cohosh Pro is not a substitute for hormone replacement therapy during menopause.
Menopause and Estrogen
As a woman approaches menopause, the signals between the ovaries and pituitary gland diminish, slowing down estrogen production and increasing luteinizing hormone (LH) secretions. Hot flashes can result from these hormonal changes. Although recent animal studies4 and a clinical trial5 have found no estrogen activity for black cohosh extracts, it seems to mimic estrogen’s action by acting as a phytoestrogen which is about 1000 times weaker than estrogen, with non of the cancer promoting effects estrogen has.
Hot Flashes
Small German clinical trials support the usefulness of black cohosh for women with hot flashes associated with menopause.6,7 A review of eight clinical trials found black cohosh to be both safe and effective for symptomatic relief of menopausal hot flashes.8 Other symptoms which improved included night sweats, insomnia, nervousness, and irritability. A clinical trial compared the effects of 40 mg versus 130 mg of black cohosh in menopausal women with complaints of hot flashes.9 While hot flashes were reduced equally at both amounts, there was no evidence of any estrogenic effect in any of the women. This trial suggests that black cohosh is best reserved for the symptomatic treatment of hot flashes associated with menopause.
Breast Cancer
There have also been studies which focused on black cohosh and breast cancer. One in particular concluded that black cohosh actually inhibits the growth rate of cancer cell’s due to the herb’s lack of estrogen-like effects in certain breast cancer cell lines whose growth is dependant upon estrogen.11