What Is Chasteberry, and What Can It Do?

Riding a hormone rollercoaster is no fun. Feeling cranky and out-of-sorts can happen whether you’re dealing with your menstrual cycle or long past those days. And for some, hormonal ups and downs can cause problems like painful periods and even infertility.

Chasteberry is a natural remedy that may help. People have used it for thousands of years to relieve symptoms related to hormonal issues. Functional medicine specialist Sobia Khan, MD, shares what chasteberry does and provides tips for trying it.

What is chasteberry?

Chasteberry is the fruit from the chaste tree, which is native to the Mediterranean region and Asia. Its scientific name is Vitex agnus-castus.

In Germany, healthcare providers regularly prescribe it for menstrual cycle irregularities, period-related breast pain and premenstrual syndrome (PMS). In the U.S., chasteberry is available over the counter in:

• Capsules.
• Extracts.
• Gummies.
• Tea.

Chasteberry benefits

Chasteberry works by reducing inflammation and balancing hormones. “It helps with conditions where your estrogen and progesterone levels rise and fall,” Dr. Khan says.

Researchers don’t know exactly how it works, but studies have shown that it has medicinal properties.

1. Reduces PMS symptoms

Tired of feeling less than your best the week before your period starts? One study found that taking a daily chasteberry tablet (20 milligrams) for three months significantly reduced PMS symptoms. Chasteberry helps with:

• Breast pain.
• Headaches.
• Mood changes, including irritability and sadness.

Chasteberry can be especially helpful for mood swings, Dr. Khan says. “PMS causes some people to feel depressed or irritable, but you can’t take an antidepressant for a few days and expect it to help. Antidepressants have to build up in your system. But you can take chasteberry as needed. It’s an anti-inflammatory that helps calm down hormones and lessen PMS-related mood changes.”

2. May help improve fertility

Infertility (inability to get pregnant) has many causes. One of them is an issue with the luteal phase of the menstrual cycle. This stage happens between ovulation (when your ovaries release an egg) and the beginning of your period (when you start to bleed).

During the luteal phase, levels of the hormone progesterone increase. This causes the lining of your uterus to thicken in preparation for a potential pregnancy. If you don’t produce enough progesterone, your uterus can’t support a pregnancy.

Luteal phase issues are often linked to conditions that cause menstrual irregularities, including:

• Endometriosis.
• Polycystic ovary syndrome (PCOS).
• Thyroid disorders.

Studies on chasteberry for infertility are promising but still in progress. Researchers found that it:

• Increases progesterone production: Participants in one small study took a 20-milligram capsule of chasteberry daily for three months. It increased their progesterone and helped normalize their luteal phase.
• Makes pregnancy more likely: Research indicates that supplements containing chasteberry may increase the rate of pregnancy in people with luteal-phase issues. One study showed that people were twice as likely to get pregnant after three months of use. Another found the rate of pregnancy was 33% higher after five months.

3. Relieves menopause symptoms

You’ve reached menopause when you haven’t had a period for 12 months in a row. And even though it seems like that would end the hormonal rollercoaster, you may still be in for one last loop. Low levels of hormones during menopause can still cause symptoms, including hot flashes and depression.

Research suggests that chasteberry might help reduce menopausal symptoms by reducing the frequency of hot flashes and night sweats and improving your mood. This may be because chasteberry contains phytoestrogens, natural substances that mimic estrogen (the hormone that your ovaries stop making after menopause).

Chasteberry side effects and risks

Chasteberry may cause mild side effects for some people. “If you take it and your body doesn’t need it, or you’ve taken too much, it can lead to nausea and stomach issues,” Dr. Khan warns. It can also cause headaches.

You should always check with a healthcare provider before taking chasteberry, as it can come with other risks, too:

• Drug interactions: Chasteberry can negatively interact with some prescription medications.
• Hormone-sensitive cancer: Because chasteberry affects hormones, it may worsen some diseases, including breast, uterine and ovarian cancer. Avoid chasteberry if you have any of these or another condition that’s negatively impacted by hormonal changes.
• Pregnancy and breastfeeding (chestfeeding): Some people say chasteberry helps increase milk supply, but there’s not enough evidence to support this claim. For the safety of your baby, don’t take chasteberry if you’re pregnant or breast or chestfeeding.

Using chasteberry supplements

Chasteberry has proven benefits for problems triggered by the ebb and flow of hormones. For many, it’s an option that works to ease uncomfortable symptoms.

You should always talk to a healthcare provider before taking any new supplement. And there are a few key things you should know about chasteberry supplements, in particular, before starting them.

How to choose the right supplement for you

Unlike other herbal remedies, it’s relatively easy to find a good formulation of chasteberry in the U.S., Dr. Khan notes. If you’d like to try it, do some research to find a reputable brand that’s tested by an independent, third-party lab.

And keep in mind that different formulations can treat different conditions. Ask your healthcare provider which formulation is right for your needs.

What’s the right dosage of chasteberry?

As with any vitamin, supplement or medication, it’s important to take the right amount of chasteberry for you — and as is often the case, this means starting with the lowest possible dose.

“People tend to take the dosage that’s written on the bottle, but that number is not necessarily what’s best for you,” Dr. Khan advises. “That’s just the amount you can take without it being toxic. It’s better to start with the lowest dose and build up from there.”

Allow two days before increasing your dosage or adding a new supplement to your routine so you have time to notice if the change leads to improvement or side effects.

Take chasteberry as needed

You don’t have to use chasteberry every day to experience its benefits. “For instance, during PMS, you may take it three times a day, according to the dosage,” Dr. Khan says. “But as your period is ending, take two, then one and then stop taking it if you feel fine.”