A herbaceous perennial plant, the medicinal nature of the Japanese knotweed is due to the high concentration of a compound called resveratrol. This HolisticZine write-up lists out the uses and benefits of Japanese knotweed.
The French Paradox!
The relatively lower incidence of coronary heart disease (CHD) in France despite the consumption of food rich in dietary cholesterol and saturated fat is often attributed to the consumption of red wine, which is rich in an antioxidant called resveratrol. The sources of resveratrol include grapes, red and white wine, Japanese knotweed, berries, etc.
The World’s Conservation Union has listed the Japanese knotweed as one of the worst invasive plant species of the world. According to the Invasive Plant Species Assessment Working Group, Japanese knotweed ranks high in terms of potential for expansion, and medium in terms of ecological impact and difficulty of control. Extremely resilient by nature, its shoots can even grow through concrete and tarmac. Once established, it could be quite difficult to eradicate. It can be found in several states in the United States. In fact, it has been classified as an invasive weed in Maine, Ohio, Vermont, Virginia, West Virginia, New York, Alaska, Pennsylvania, Michigan, Oregon and Washington state, and Colorado. Though its potential for expansion has made it an unpopular plant, there’s a lot more to this plant than its invasive potential.
Japanese knotweed has been used in Chinese medicine due to its therapeutic properties. Japanese knotweed belongs to the Fallopia genus and Polygonaceae family. Its scientific names include Fallopia japonica and Polygonum cuspidatum. It is also known by other names such as fleeceflower, monkeyweed, Hancock’s curse, Himalayan fleece vine, elephant ears, etc. The following sections provide some information on the health benefits of this plant.
Constituents of Japanese Knotweed
While young leaves and shoots of this plant are consumed in Japan, its flowers are a source of nectar for honeybees. Parts of this plant have been used in the traditional Chinese Medicine. One of the main constituents of this herbaceous plant is resveratrol, which is primarily responsible for many of its therapeutic properties.
Japanese Knotweed Leaves
Japanese Knotweed Shoots
Japanese Knotweed Flowers
Here’s a list of some of the phytonutrients or constituents of Japanese knotweed:
◆ Emodin monomethyl ether
◆ Polydatin (piceid)
◆ Oxalic acid
◆ Amino acids
◆ Anthraquinone glycosides
It also contains minerals such as calcium, bromine, iron, iodine, copper, barium, manganese, phosphorus, zinc, etc.
Health Benefits of Japanese Knotweed
Japanese knotweed contains several phytonutrients, but its medicinal properties can be primarily attributed to the substantial amount of resveratrol present in this plant. Being a plant with high resveratrol content, Japanese knotweed is often used for making resveratrol extract or pills.
◆ Animal studies have shown that polydatin present in Japanese knotweed can help lower lipid levels.
◆ It is used in many skincare products in Asia due to its anti-aging effects. It can also be used to heal minor burns or wounds, as resveratrol is antimicrobial and anti-inflammatory in nature.
◆ It is believed that resveratrol inhibits aggregation of platelets. It has the ability to reduce the viscosity of blood, which in turn can lower the risk of blood clots that can cause arterial blockage, thereby leading to cardiovascular problems.
◆ Herbal practitioners believe that this herb could be quite effective against bacteria from the genus Borrelia. These are responsible for causing Lyme disease, which occurs when one is bitten by ticks infested by the bacteria.
◆ Japanese knotweed also contains emodin, which is believed to help regulate bowel motility, thereby stimulating bowel movements. Thus, it can act as a laxative.
◆ Antioxidants are substances that can help prevent damage caused by free radicals. Cellular damage that is caused by free radicals is associated with aging, cancer, and a host of ailments. Thus, incorporating antioxidants in the form of food or supplements can prove to be beneficial.
◆ Animal studies have suggested that the use of resveratrol can prove beneficial in providing protection against neurodegenerative processes that could contribute to Alzheimer’s disease.
◆ Trans-resveratrol present in this plant acts like a phytoestrogen. Thus, taking the supplement during menopause might prove to be beneficial.
◆ Animal studies have also suggested that resveratrol has anti-cancer effects. Studies on rats suggest that it is antimutagenic in nature. Animal studies show that it can inhibit enzymes that promote the growth of tumors. It has also exhibited anti-tumor effects in neuroblastomas.
Contraindications or Warnings
◆ Caution must be exercised, as Japanese knotweed contains oxalic acid, which is known to cause certain adverse effects.
◆ It is advisable not to take these supplements, if one has been diagnosed with estrogen-sensitive cancers.
◆ Since it is believed to inhibit clotting, there could be adverse drug interactions in case of individuals who are taking other anticoagulants.
◆ It should be consumed in moderation, as it works as a laxative.
◆ Since there’s a lack of evidence regarding its effects on pregnant women and nursing mothers, it’s advisable not to take these supplements during pregnancy or while breastfeeding.
On a concluding note…
Claims have been made regarding the effectiveness of Japanese knotweed in inducing weight loss, and reducing hypertension, insulin resistance, and mortality in people affected by diabetes. The manufacturers of the supplements claim that it is a potent antioxidant that can help strengthen one’s immune system and lower the risk of several diseases. However, Japanese knotweed is sold in the form of a nutritional supplement, which is why its sale is not regulated by the Food and Drug Administration. Moreover, human trials are needed to prove its efficacy and safety. According to some animal studies, this plant contains certain tannins that could are carcinogenic and inhibit digestive enzymes. Thus, consult your healthcare provider before you start taking these supplements. Avoid indiscriminate use of these supplements.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert or herbal practitioner.