We have looked at the health effects of a number of herbs here at healthyfocus. Many of these are pretty well known and commonly used while others are slightly more obscure. Pueraria mirifica may not trip off the tongue nor be especially well-known. However, a growing body of research suggests it has a number of potential health benefits.
What is Pueraria mirifica?
Pueraria mirifica, is an herb believed to be native to Burma. These days, it is mostly grown in Thailand, where it is referred to as Kwao krua.
The roots of the plant have been used for centuries by traditional Thai practitioners to promote general youthfulness and help rejuvenate both men and women. (1)
Pueraria mirifica contains various plant compounds called phytoestrogens which mimic the effects of estrogen in the body. (1)
Because of the plant’s powerful, estrogenic effects, it is commonly sold in supplementary form to women to help treat menopause symptoms.
Health Benefits of Pueraria mirifica
To Ease Menopausal Symptoms
Pueraria mirifica has predominantly been used to help women overcome the common symptoms associated with menopause.
Estrogen is a hormone involved with many of the body’s important functions. Some of the hormone’s primary roles in women are to regulate the menstrual cycle and mood and the development of certain sexual characteristics. (2)
When women get older, they produce less estrogen and this often leads to uncomfortable symptoms particularly during and after menopause.
Phytoestrogens, like those found in Pueraria mirifica, can effectively mimic the effect of estrogen in the body. Some studies have found that the herb is an effective treatment against common menopausal symptoms.
Several studies have found that treatment with the herb helped significantly reduce symptoms linked to the menopause. these include irritability, hot flashes, irregular periods and vaginal dryness. (3) (4) (5)
Despite these positive results, a review in 2018 recommended caution. The studies were small, lacked standardization regarding the exact supplement used and had certain design flaws. (6)
More studies are necessary before we can say for sure just how effective the herb could be in treating menopause symptoms. However, it remains a popular choice for women in many Southeast Asian countries.
We have long known that antioxidants are vitally important for human health. These compounds have a wide range of therapeutic benefits for the human mind and body. They are responsible for preventing or even reversing the oxidative stress in the human body that can lead to illness, disease and premature aging.
There is some evidence that Pueraria mirifica has antioxidant potential. One laboratory study, published in 2008, found that a compound found in the plant called puerarin exhibited antioxidant activities. (7)
Another study found that the phytoestrogen compounds present in the herb could help improve the function of antioxidants found in the body. The animal study looked at the effects of an extract of the plant on mice with estrogen deficiency.
The results showed that the mice fed on Pueraria extract experienced a significant boost in antioxidant level compared to mice given a synthetic estrogen. (8)
The herb has traditionally been used to rejuvenate the body. These results suggest that this traditional use may have merit but more research is necessary.
Pueraria mirifica has traditionally been used to treat a range of female issues and studies suggest that the herb could be used to boost vaginal health.
According to research, the herb could be applied topically to improve vaginal tissue health and to treat vaginal dryness especially in women as they age.
One animal study looked at the effects of a topical gel, containing Pueraria mirifica, on a group of postmenopausal monkeys. Applying this gel topically had significant benefits including improved vaginal tissue health, skin tone and pH levels. (9)
These findings are supported by a more recent study on postmenopausal female subjects. The 12 week long study involving 71 women compared the topical application of a Pueraria cream with an estrogen cream.
The researchers found that the cream containing Pueraria mirifica helped significantly improve vaginal dryness and irritation. However, the researchers also concluded that the standard estrogen application was even more effective. (10)
These results are certainly promising and suggest that the herb deserves more research in the future. the herb appears to be well-tolerated and effective when applied topically but whether it can be used as a natural replacement for conventional treatments is still open to debate.
Improved Bone Health
Because of its estrogen-mimicing abilities, a number of animal studies have evaluated the effect of Kwao krao extract on bone health.
One study looked at the effects of Pueraria extracts on mice with estrogen deficiency, in particular the ability of the herb to prevent osteoporosis. The results were promising. The researchers found that the mice treated with higher doses of the herb benefited greatly in terms of bone mineral preservation and bone health. (11)
Another animal study looked at the effects of Pueraria mirifica supplements on the bone health and density of postmenopausal monkeys. The results indicate that the animals treated with the herb maintained better bone density and health compared to the animals in the control group. (12)
These studies suggest that the herb might have a role to play in the treatment and prevention of bone diseases like osteoporosis. However, at the time of writing, there have been no studies done on humans.
Heart Health Benefits
What can be more important than a healthy heart? the good news is that many herbs can help and early studuies suggest that Pueraria mirifica is one of them.
Again, the findings are linked to the presence of extrogen-like compounds found in the plant. Poor heart health has been linked to a drop in estrogen levels at menopause.
Estrogen plays a role in fat and sugar metabolism. When estrogen levels are reduced, this can have a negative impact on heart health including increased cholesterol levels and inflammation. It can also lead to unwanted weight gain.
One animal study looked at the effects of Kwao krua extract on the heart health of rabbits with an estrogen deficiency. The researchers found that the herb significantly improved the function of blood vessels when compared with the control. (13)
As well as improved arterial function, the plant might also benefit the heart because of its effect on cholesterol.
HDL cholesterol (commonly referred to as the ‘good type’) plays an important role in keeping a person’s arteries clear of plaque. LDL cholesterol (or the ‘bad type’) is linked to an increased risk of cardiovascular disease.
A study involving 19 post-menopausal women found that treatment with Pueraria supplements helped boost HDL cholesterol levels by 34% while simultaneously decreasing LDL levels by 17%. (14)
These results certainly appear promising for the role of Pueraria mirifica in heart health. More studies in the future would help clarify exactly how effective the plant might be in preventing or reducing the risk of heart disease.
Estrogen also plays a vital role in brain health and maintaining a healthy nervous system.
Because the plant contains estrogen-like compounds, Pueraria mirifica might also help maintain brain health and protect the nervous system as estrogen levels fall while we age.
Studies have put this theory to the test and results have been promising.
One study looked at the effects of a compound called miroestrol, which was isolated from the plant, on a group of mice with estrogen deficiency. The researchers found that the mice given this compound experienced significant brain benefits including a reduction in oxidative stress and mental decline. (15)
While the results of this study are promising, we need further research on the effects of the plant on human subjects. However, animal studies suggest that it may have significant benefits for brain and nervous system health.
When it comes to the battle against cancer, scientists have increasingly turned their equipment towards nature. Studies suggest that a number of plants have anticancer potential and Pueraria mirifica may be one of those.
According to laboratory and animal research, the plant might help slow down the growth and spread of certain cancerous cells.
Laboratory studies have found that the phytoestrogen compounds found in the plant have anti-proliferative properties and can inhibit breast cancer cell growth. (16)
A study done on mice found that a compound called miroestrol, isolated from the plant, had an anticancer effect on the animals. (17)
These results are certainly promising but how much of an effect the plant would have on humans remains unclear and untested.
How to Use Pueraria Mirifica
Pueraria mirifica is available in supplementary form online. It is sold in a number of supplementary forms including capsule and tablet form but is also available as an ingredient in topical creams and soaps.
There is not enough data regarding the appropriate dosage of supplements made with the herb. Make sure that you buy the product from a reputable supplier and follow the instructions on the label carefully.
The majority of research has found that a dose of between 25 and 100 mg is safe for the majority of people and no adverse reactions have been reported.
Precautions and Potential Side Effects
Pueraria mirifica appears to be safe for the vast majority of people when taken at a dose between 25 and 100 mgs. very few adverse side effects have been reported and the herb has been used in Southeast Asia for a very long time.
Nevertheless, you should always speak to your doctor before taking a new herbal supplement. This is especially the case if you are suffering from any pre-existing disorder or are taking prescription medications.
Women who are pregnant or breastfeeding should not take any herbal supplements without their doctor’s ex[press approval.
We also have no safety data regarding the effects of the herb on young children.
Pueraria mirifica is a medicinal plant that has been used by traditional practitioners in Thailand for many years. While it is used in some other Southeast Asian countries, Thailand is still the biggest producer and consumer of the plant.
Also known as kwao Krua, the herb is a rich source of phytoestrogens making it a popular remedy for a range of women’s ailments. In particular, the herb is used to treat many of the unwanted symptoms associated with menopause.
Studies have found that Pueraria mirifica may indeed help treat many of these unwanted symptoms including vaginal dryness, irritability and hot flashes.
Studies have also found that Pueraria mirifica has other potential benefits. these include antioxidant potential, heart and brain health benefits and protection against cancer.
Although research into the effects of the plant is growing, more evidence is needed especially regarding its effects on human subjects.
Pueraria mirifica appears to be safe when taken in the recommended doses but it is important to speak with your doctor before using this or any other herbal remedy.