Comfrey is a shrub that grows in Europe, parts of Asia, and North America. It can grow up to five feet tall and produces clusters of purple, blue, and white flowers. However, it’s the long, slender leaves and black-skinned roots that the plant is most famous for.
Both the root and leaves are well known for their healing properties until they were found to be both liver toxic and carcinogenic. Most countries have banned the sale of oral comfrey and do not recommend using topical comfrey on open wounds, but comfrey may be acceptable for short term use (under 2 weeks) if used on the skin. That’s because they contain chemical substances called allantoin and rosmarinic acid. Allantoin boosts the growth of new skin cells, while rosmarinic acid helps relieve pain and inflammation. Extracts are made from the roots and leaves and are then turned into ointments, creams, or salves. These solutions typically have from 5-20 percent of comfrey in them.
You can purchase them from most health stores. Read on to learn what they can do for you.
It’s Big in Japan
Comfrey has a long history as a medical remedy. In Japan, the herb has been harvested and used as a traditional treatment for over 2,000 years. Comfrey was originally called knitbone because of its use in healing muscle sprains, bruises, burns, and other joint inflammation. Europeans also applied comfrey to the skin for treating inflammatory conditions, such as arthritis and gout, and took the herb by mouth for treating diarrhea.
Today comfrey is still used as an alternative remedy for joint and muscle pain, as well as unopened wounds. Ointments, creams, and other topical solutions are applied directly to the skin on the affected area. The herb may also be combined in salves with other herbs like aloe and goldenseal to heal minor wounds.
Some clinical research does support claims that comfrey is helpful in healing wounds. One study found that creams with 10% comfrey concentration can effectively speed up healing time. However, comfrey should not be used for open cuts or scrapes.
Applied to the skin, comfrey can effectively reduce pain and inflammation caused by arthritis as well as injuries like sprains and muscle strains. One study found that comfrey extract ointment can help mobility and relieve pain in people with knee osteoarthritis. Other research shows that it can reduce the pain and swelling from a sprained ankle. Some evidence also suggests that comfrey may be helpful in treating upper and lower back pain.
Don’t Eat It
Historically, comfrey leaves were eaten as a vegetable. People would take the herb by mouth to treat stomach issues such as ulcers, colitis, and diarrhea. Dried comfrey root and leaves can also be prepared as tea. However, as noted above, today eating or taking any form of comfrey by mouth is not recommended because it’s considered unsafe.
It’s Only Safe on the Skin
Comfrey contains pyrrolizidine alkaloids. These are dangerous chemicals that can cause cancer and severe liver damage (and even death) when taken by mouth. For this reason, the Food and Drug Administration (FDA) as well as many European countries have banned oral comfrey products. You should never take comfrey by mouth, but it can be used safely on the skin for short-term treatment. Comfrey in any form is not safe for children, elderly people, pregnant or breastfeeding women, or anyone with liver disease.
Your skin can still absorb comfrey’s harmful chemicals. For this reason, comfrey should not be applied to open wounds. Experts recommend using creams and ointments for a short period of time (no longer than 10 days in a row) and under your doctor’s supervision.