What is Comfrey? 10 Things to Know About This Powerful Plant

Comfrey is a flowering shrub native to Eurasia.

Early colonial settlers transported it across the Atlantic several centuries ago. By the 18th century, the Indigenous peoples of North America were using comfrey as an herbal medicine to treat various health concerns, including digestive and reproductive issues.

You’ll find comfrey growing in moist, shaded grasslands and river banks. Depending on where you live, the comfrey plant may also go by other names, including:

• Blackwort
• Boneset
• Slippery-root
• Knitbone

It’s no accident that some of comfrey’s alternative names include “knitbone” and “boneset.”

One of the plant’s most widespread medicinal uses, both historically and in more recent times, is to treat bone and joint issues:

• Broken bones and bone fractures
• Arthritis
• Back pain
• Sprains and strains

Comfrey is also popular in traditional medicine for ailments such as:

• Organ health concerns, such as gastritis (stomach inflammation), liver problems and ulcers
• Skin problems, such as insect bites and even signs of ageing
• Wound healing
• And more

Traditional medicinal applications of comfrey are seemingly endless, but modern clinical trials have specifically honed in on comfrey’s effectiveness in a handful of key areas.

Wound healing is one of them.

Comfrey is very high in rosmarinic acid (RA) and salvianolic acid. These compounds have very high antioxidant and anti-inflammatory activities. This may improve healing and recovery from wounds.

Traditional healers have often used comfrey as a poultice when bandaging injuries. One study found that applying comfrey to wounds shortened total healing time by almost three days.

Kids love to play, but playtime isn’t without its risk. Nearly half of all sports-related injuries occur in young children.

Comfrey may work as a potent, natural recovery aid for injured kids.

When used in a cream, comfrey significantly reduced pain and helped restore mobility in children ages 4 to 12. There were also no reported adverse side effects in this study.

However, experts warn that more research needs to be done, specifically on the short-term and long-term effects on young children.

Arthritis affects more than one in four adults, according to the Arthritis Foundation.

Numerous studies have researched the traditional use of comfrey for joint and bone health, and found that topical applications may:

• Reduce joint stiffness
• Reduce joint pain
• Improve mobility
• Restore daily function compromised by arthritis and joint health problems

In some studies, comfrey also outperformed other natural joint health remedies, such as topical use of essential oils.

Clinical trials report that comfrey significantly reduces chronic and acute muscle pain, outperforming placebos and other remedies in several different studies.

It has specifically been shown to help with:

• Muscle swelling
• Muscle pain
• Pulled and strained muscles

One of the more well-researched areas of interest is lower back pain. Seven out of 10 adults will experience low back pain at some point in their lives, with muscle sprains and strains ranking as the most common triggers for back pain.

Numerous studies suggest that comfrey effectively manages back pain by soothing these muscle sprains and strains.

The exact reasons why comfrey works so effectively remains a mystery.

“Comfrey constitutes a traditional medicinal plant with a long-standing therapeutic history,” reports a recent study published in the Frontiers in Pharmacology journal. “Today, its topical use is based on its analgesic and anti-inflammatory effects, which have been substantiated by modern clinical trials. However, the molecular basis of its action remained elusive.”

More research needs to be done. However, scientists currently think the plant’s medicinal properties come from compounds and chemicals like:

• Allantoin, which improves cell division (this may assist in wound and injury recovery)
• Phenolic acids that work as potent antioxidants
• Chemicals that impair the inflammatory process
• Chemicals that inhibit the growth of pathogens

The comfrey plant’s roots, stems and leaves are all used in herbal medicine. You can typically find comfrey in products such as:

• Creams
• Salves
• Ointments
• Lotions

Apply these comfrey products according to the labelled instructions, since different manufacturers will incorporate different concentrations of comfrey’s active ingredients.

In the past, comfrey was also used orally, both as an oral supplement and even as a mouth rinse or gargle. However, internal usage raises significant safety concerns and should be avoided.

Comfrey is very high in many different types of pyrrolizidine alkaloids. These alkaloids are very toxic when ingested.

In humans and animals, consumption of comfrey has been linked to increased risks of:

• Cancer
• Liver health problems
• Lung health problems

Other potential side effects from taking comfrey tea, capsules and other oral applications include:

• Abdominal pain
• Nausea
• Fatigue
• Diarrhea

For these reasons, comfrey should only be used topically (and never on open wounds). You should also avoid taking it orally.

The latest studies back up what traditional medicinal experts have known for centuries: Comfrey may be an effective and natural treatment for many health concerns.

But just because it’s natural doesn’t mean it’s completely harmless.

Talk to your doctor before trying comfrey. Studies are ongoing, and research is still unclear on how some of the plant’s compounds might interact or interfere with other natural treatments, supplements or medications you’re using.