The Spartan Guide to Chasteberry

The Claim Native to Central Asia and the Mediterranean, the berry of the chaste tree has long been thought to tamp down one’s sexual drive, and monks used it in the Middle Ages to stay chaste (get it?). Available as a liquid extract, essential oil, and pill, chasteberry is used today to treat menstrual problems, menopause symptoms, and other hormone-related conditions.

The Evidence There’s no evidence that chasteberry will inhibit your libido. But in the past 50 years, about 30 European trials of chasteberry have shown that it helps with menstrual disorders. The problem: Most of those trials were pretty poorly designed. Either they were unblind, meaning that both patients and experimenters knew who was using what (hello, placebo effect!), or they lacked a control group to compare the herb to.

More recently, a few small-but-high-quality studies (that’s double-blind, randomized controlled trials, for you stats nerds) have found some evidence that chasteberry’s ability to improve symptoms of PMS seems legit. Data on its efficacy for irregular periods and fertility disorders is weak.

Still, holistic doctors still recommend the berry for general female-friendly effects. “Chasteberry is great for many gynecological conditions associated with estrogen dominance, such as PMS, cyclic breast pain, irregular ovulation, and perimenopause,” says Bronwyn Fitz, M.D., an OB-GYN at the Blum Center for Health in Rye Brook, New York. Chasteberry helps your body produce more progesterone, she explains, which helps alleviate estrogen-related symptoms, like moodiness, breast tenderness, painful periods, and hot flashes. It’s well-tolerated and rarely causes side effects.

How to Use It A typical dose is 200 to 500 milligrams per day. Because chasteberry impacts your body’s hormone production, it’s wise to avoid it if you have a hormone-sensitive cancer, or if you’re pregnant or nursing. Those on hormonal birth control or dopamine-related medicines (e.g., certain Parkinson’s Disease drugs) should also steer clear. “It does take a while to see the full impact, so stick with it for at least three months before deciding if it’s working for you,” Dr. Fitz says.