Comfrey, once called “knitbone” by medieval herbalists, has long been prized in traditional medicine for its ability to soothe aches and promote skin healing. But it’s important to understand which benefits are truly supported by clinical studies and which remain anecdotal.
Today we’re sharing four benefits ascribed to comfrey that are research-backed and not simply herbal lore.
1. Relieves Pain and Swelling from Sprains
One of the most robust areas of research for comfrey is in treating acute ankle sprains and soft-tissue injuries. A 2005 randomized trial with 164 people compared a comfrey root extract cream to diclofenac gel (a topical NSAID) in the treatment of ankle sprains.
This study focused on two variables: pain and swelling. They found that the comfrey extract significantly reduced pain, swelling, and improved mobility. Although it was a small sample size, the researchers concluded that the comfrey extract was not only beneficial, but “may be superior to Diclofenac gel.”
2. Eases Symptoms from Osteoarthritis in the Knee
There have been several studies focused on comfrey’s effects in treating osteoarthritis symptoms, particularly in the knee. One study with 220 patients tested the effects of Kytta-Salbe, a German comfrey ointment. Over a three week period, patients were administered either the Kytta-Salbe or a placebo, and assessed for both pain at rest and movement. They found the comfrey ointment not only reduced pain, but also increased mobility.
Another smaller study also found a comfrey cream to be highly effective for treating pain and stiffness caused by osteoarthritis. Interestingly enough, they found there was not a large difference in effectiveness between a 10% vs 20% comfrey root extract. Since the dataset was small, it would be interesting to test this on a larger scale and see what the ideal concentration of comfrey extract is.
3. Relieves Back Pain
This trial involved 120 patients, split into a placebo group and a verum group administering a comfrey root extract ointment 3x a day. While this trial was very short (only 5 days), the pain intensity was much lower in the test group applying the comfrey ointment. Researchers also reported the comfrey ointment could be effective in as little as an hour, making it very fast-acting.
4. Promotes Minor Skin Healing
While comfrey’s traditional reputation as a “knitbone” herb is a bit exaggerated, it’s commonly used for for minor skin wounds. Comfrey supports healing of minor abrasions, bruises, and superficial skin injuries due to allantoin, the compound in comfrey that stimulates cell proliferation.
A study involving 278 patients with abrasive wounds examined the wound healing effects of comfrey, using a topical solution with 10% comfrey leaf concentrate. While wound healing rate varies per person, making it difficult to pinpoint, researchers estimated that healing was about 2.97 days faster with the comfrey extract.
What’s not backed by science?
Claims that comfrey can help actually heal bones or connective tissue faster, or treat arthritis, are not currently supported by clinical research. The studies involving comfrey for osteoarthritis and back pain indicate that comfrey may be able to reduce pain and inflammation across a wider range of injuries. But nothing has shown that comfrey can actually speed up internal healing.
Where to learn more
Because the studies done on comfrey are few and limited, there may be many other medicinal benefits that are not yet clinically-backed. We’re always keeping an eye out for new research and hope more natural remedies get the attention they deserve.
You can learn more about comfrey at the links below.
👉Click here for a more in-depth clinical view of comfrey.
👉Click here for an overview of comfrey's chemical composition.
Disclaimer: Comfrey is not recommended to take internally, because it contains pyrrolizidine alkaloids (PAs), which are linked to liver toxicity and possibly cancer. We are not medical professionals, and are not offering medical advice. Please consult your doctor or a medical professional if you have any medical concerns.
Comments