Are Benefits of Vitex or Chaste Tree Berry Bogus?

Its name comes from the word chastity, as that was its most famous use. Clergymen wishing to remain celibate would eat this berry, because it was believed to decrease sex drive. In the middle ages, it was ground and used as a spice in monasteries. It became known as Monk’s pepper.

Later on, this “benefit” of supporting celibacy was thought to be just an old wives’ tale. It wasn’t until this century when scientific findings started to suggest that actually, it might not be bogus after all.

About 15 years ago, a German university identified several new phytoestrogens in the plant. How potent they are compared to soybeans and flaxseeds is yet to be determined but indeed, it’s feasible that clergymen who were consuming these back in the day really did achieve chastity more easily with them. (1)

In this case, what’s bad for men might be good for women in multiple ways.

What is it?

Photo by H. Zell [CC BY-SA 3.0], via Wikipedia

Chasteberries smell like peppermint but have a pungent and peppery taste. It’s not sweet or particularly enjoyable. They have only been used for remedies and herbal tea, rather than as a food you eat for flavor.

Is vitex and chasteberry the same thing?

Yes, there’s no difference between them. They’re commonly called vitex because the plant’s scientific name is Vitex agnus-castus.

When translated from Latin, it means “to weave or tie up.” The fact that may conjure up images of a chastity belt is no coincidence.

Health benefits

While none are conclusively proven, what follows are some of the most common uses for the vitex berry and what formal science (if any) there is to support each.

1. Aphrodisiac

It may be a libido killer for men but for women, it has a reputation of boosting sex drive. Even Plato described the herb’s aphrodisiac effects in his writings (circa 428 to 348 BC). You can read more about the history in Botanical Medicine for Women’s Health.

When it comes to abnormally low sexual arousal in women, it’s officially called female sexual dysfunction (FSD). It’s often associated with a decline in estrogen levels, which is a reason why a common side effect of menopause. A review of the research on this topic concluded:

“Studies of these plants [including vitex berry] indicate that they may be useful as a possible alternative and/or complementary approach for studies aimed at the treatment of FSD. At this time, however, this review cannot recommend a plant that has a strong enough level of evidence for treatment of FSD.”

There are no clinical human studies measuring sexual arousal in women, which means it’s speculative but remains possible, given the plant’s phytoestrogen content. (2)

2. May help premenstrual syndrome (PMS)

Irritability, mood swings, tender breasts, weight gain from abnormal food cravings, acne, and depression are all possible side effects of premenstrual syndrome. For women affected, these can begin one to two weeks before starting a period.

Changes in hormones, as well as chemicals in the brain like the neurotransmitter serotonin, are believed to be the cause of PMS. (3)

What does vitex do to hormones?

In female rats, vitex fruit supplements have been found to increase levels of estrogen and progesterone by up to 432% as detected in vaginal smears. Overall blood levels went up 77%.

In male rats injected with vitex extract, there was a slight reduction in testosterone and luteinizing hormone levels. In the only human study done, no changes were observed in men after 20 days of using supplements in dosages ranging from 120 to 480 mg. (4) (5)

Does it work for PMS?

There is insufficient data to determine if the berries alter hormonal and serotonin levels in women. A total of 7 human clinical trials on vitex and PMS have been published. Although preliminary, the results suggest it has a positive effect on reducing symptoms in women suffering from premenstrual syndrome.

The results are noteworthy, as seen in this chart from a placebo-controlled and double blinded study involving 128 women.

You can see how the control groups didn’t improve much, while the case group (those taking the chaste berry supplements) experienced improvement for a wide variety of PMS side effects including headaches, nervousness, depression, and breast pain. (6) (7) (8) (9) (10) (11) (12)

3. Less breast tenderness and pain

With 5 clinical trials having evaluated this, it’s the next most studied benefit in humans. 4 of those 7 were among the PMS trials mentioned above. In addition, there is one trial that looked at only breast pain, regardless of cause.

Technically known as cyclic mastalgia, 159 women participated and were divided into 3 groups:

• 53 got chasteberry
• 53 got flax powder
• 53 got placebo

Each group took these daily for 2 months and here were the results:

Both chasteberry and flax appear to reduce the pain and sensitivity of swollen breasts in women.

What’s interesting to note is that flax is the highest known phytoestrogen source in the world, more than black cohosh and soybeans. Based on these results, perhaps chaste has the same or a similar potency as flax. (13)

4. Good for acne

Since it may affect hormonal levels in women, the Department of Pharmacology at the University of Rome reports the side effects of chasteberry include nausea, headache, GI abnormalities, menstrual disorders, rash, and acne on the face. More often than not, it’s believed to improve these problems rather than cause them, when they are due to PMS. (14)

Even though they were not a primary focus in the PMS trials, a number of them noted improvements in outbreaks of pimples and blackheads.

If you go and look at individual patient case studies, there’s literature as far back as the 1960’s which talks about acne vulgaris improvement after using vitex, irrelevant of PMS. (15)

5. Weight loss success stories

Does vitex cause weight gain?

While some believe the V. agnus castus plant makes you gain weight, this side effect has not been observed in a clinically-relevant matter. There is actually reason to believe the berry boosts weight loss, since it may help with PMS and menopause.

Those are often accompanied by unwanted weight gain. Hormonal changes may alter body composition and spur appetite in an undesirable way.

If the chaste tree berry helps with weight, so far no studies have been done to evaluate it. On supplement reviews, you will come across success stories, but that’s about as much evidence as you will find today.

You will see agnuside amounts listed on some supplement labels. It’s a glycoside found in the vitex herb at a concentration of 0.3-0.5%. Whether or not it’s responsible for effects on weight or anything else is yet to be determined.

6. Infertility due to infrequent periods

Does chasteberry increase fertility?

What it does for fertility remains hypothetical, as very few scientific studies have looked at this. The Department of Anthropology at the University of Mexico observed “abrupt and dramatic increase in urinary progesterone levels” of wild chimpanzees in Tanzania after consuming vitex berry.

This occurred during the short annual fruiting season of the berrie. They naturally grow in Gombe National Park and the chimps gorge on them during this time. Even though the progesterone skyrocketed, both males and females had insignificant changes in estrogen and testosterone. (16)

If this is occurring in humans, it might help women conceive in certain infertility scenarios.

Progesterone helps support a developing embryo. Doctors don’t prescribe progesterone pills to get pregnant, but they do use vaginal and intra-muscular injections.

Only one human study has evaluated chasteberry for fertility. It was randomized, double-blinded, and placebo-controlled.  A total of 67 women with hormone-related sterility participated.

The form used was Phyto Hypophyson L, which is a liquid herbal drug sold in Germany. It’s not available in the US, UK, Canada, or elsewhere. It’s a complex rather than a stand-alone vitex supplement.

Using a dosage of 50 liquid drops, taken 3x daily over the course of 3 menstruation cycles, the following was observed:

“…spontaneous menstruation, improved concentration of progesterone in the luteal phase, shortening of the cycle, earlier ovulation, and pregnancy was achieved in 38 out of 67 women.”

The women who had infrequent menstrual periods (oligomenorrhea) seemed to achieve the most success. For the women overall, the results were not statistically significant when compared to placebo. For that reason, they only recommended it for women with oligomenorrhea, to use for a period of 3-6 months. (17)

7. May help polycystic ovary syndrome (PCOS)

This condition affects women of reproductive age. The ovaries or adrenal glands produce more of the male hormones than what’s normal for a woman to have. This can result in painful cysts that grow on the ovaries as well as irregular periods, growth of a mustache and other unwanted hair, weight gain, acne, and infertility. (18)

You will come across numerous reviews of using chasteberry for PCOS and the symptoms that disorder can cause, such as hair loss or growth, pelvic pain, etc. While there is a fair amount of data to suggest this herb might boost female sex hormones, there is limited work specific to PCOS.

Upon reviewing the evidence, a group of Australian scientists reported:

“Vitex agnus-castus contains a variety of compounds which bind to dopamine type 2 (DA-2) receptors in the brain; reduce cyclic adenosine mono phosphate (cAMP) and lowered prolactin secretion.”

When comparing various herbal medicines and remedies purported to help PCOS, their conclusion stated:

“The quality of the evidence is variable and strongest for Vitex agnus-castus and Cimicifuga racemosa in the management of oligo/amenorrhea and infertility associated with PCOS.”

Cimicifuga racemosa is black cohosh, which is another well-known supplement for women. (19)

8. Menopause symptom relief

Does vitex help with menopause?

There’s is no evidence that it can delay menopause, but phytoestrogens in the berries may lessen the symptoms of menopause including hot flashes, vaginal dryness, and insomnia. How it works is by augmenting naturally lower female sex hormones, with similar molecules found in plants.

Known as phytoestrogens, these molecules are believed to act similar to real estrogen when in the human body.

This effect remains possible and even likely, though it’s not considered unproven. For that reason, vitex and dong quai (female ginseng), black cohosh, and soy isoflavones are not recognized as medical treatments for menopause.

For this plant and menopause, only one double-blinded and placebo-controlled human study has been published. 93 women participated and some were given an herbal combination of chasteberry and St. John’s wort. The dosage used was no better than placebo for alleviating hot flashes and other menopausal symptoms. (20)

While not blinded or placebo controlled, two human studies took place with vitex essential oil. In total, 75 women participated and the results claimed (21):

“…indicated strong symptomatic relief of common menopausal symptoms.”

9. Lactation support

As an herbal remedy, particularly in Europe, vitex has long been used to purportedly increase milk supply. Along with fennel, fenugreek, and marshmallow, chasteberry tea and supplements have been suggested for breastfeeding mothers.

The problem is there aren’t clinical studies of using it for this purpose, nor has it been confirmed to be safe while pregnant or breastfeeding.

Although not proven, there’s better support for fenugreek and milk thistle as being galactagogues (lactation agents). (22)

10. Endometriosis and uterine fibroid research

These are two of the most common gynecological disorders in women. With endometriosis, tissue normally found inside the uterus grows on the outside. Uterine fibroids are noncancerous growths within the uterus.

Although two very different things, both can adversely affect fertility and some research suggests they seem to appear together. It’s been proposed they might share a common cause, at least sometimes. (23)

Does vitex help endometriosis?

Contrary to what some bloggers claim, there is virtually no scientific data on measuring the effects of chasteberry on endometriosis. Not even animal research has been done on this topic.

Some women report using a vitex dosage for uterine fibroids of 1,000 mg (2 capsules) every morning. While they may report improvement during their next cycle, there’s no research to validate these claims or even support their likelihood.

In theory, if this plant influences hormones in a way that would benefit either of these conditions, it may work. Though it’s important to emphasize that the causes of fibroids and endometriosis are poorly understood.

Vitex side effects

• Headache
• Upset stomach
• Nausea
• Itch/rash
• Difficulty sleeping
• Abnormal menstrual flow
• Weight gain
• Unknown pregnancy safety
• Unknown breastfeeding safety

This supplement is generally considered to be safe when taken by mouth as directed. Adverse reactions were uncommon in the human studies and some report none whatsoever. Many of these side effects, such as gaining weight, do not have clinical data to support them. However since some supplement reviews make that claim, it’s worth mentioning.

Vitex supplements may have drug interactions with hormone treatments and medications for Parkinson’s disease, schizophrenia, and other psychotic disorders. This is because vitex berry and derivatives of it may affect dopamine levels in the brain and possibly alter levels of hormones.

Even though some believe vitex can help fertility, PCOS, abnormal periods and other gynecological problems, it’s possible that an adverse reaction may result instead. Our body carefully balances hormone levels and having too little or too much of a given type, as well as rapid changes in them, can backfire. Even when the given hormone would logically seem to benefit from an increase.

What is it good for?

While there is a fair amount of science to suggest the chaste tree berry may offer several benefits for women’s health, all of them remain unproven. It is possible that vitex tea and supplements may work for PMS, PCOS, menopause, and some fertility concerns, but much more research needs to be done on each of these topics. Most don’t seem bogus, but they are far from certain. At least as of today.

What it says on a bottle of Nature’s Way.

It should only be used as a dietary supplement and not for any disease/condition. Please consult your doctor before using.

As a dietary supplement, the recommend dosage for chasteberry capsules ranges from 400 mg to 1,000 mg, taken one to three times daily. That’s according to the directions listed on the brands Gaia Herbs, Nature’s Way, Solaray, NOW Foods, and Pure Encapsulations.

On Amazon you can get Gaia Herbs and Nature’s Way, which appear to be among the most popular.

There’s also an organic essential oil but it is for aromatherapy use. For internal use, Nature’s Answer makes an alcohol-free tincture that uses a dropper.


These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.