Willow Bark: Nature's Aspirin

What’s Willow Bark?

Did You Know?
For over 2,000 years, willow bark has been used in Chinese medicine for its anti-inflammatory and pain relieving properties.

When most people think of the willow tree, they think of Harry Potter or their favorite Disney film. But did you know that the willow — or, more precisely, its bark — is Mother Nature’s rival to aspirin? As interest in complementary and alternative medicine grows elsewhere, it’s now being used around the world as an alternative to aspirin.

Willow bark comes from the branches of two- to three-year-old willow trees. Types of willow trees and shrubs grow all over the world, except for Australia and Antarctica. The white willow and black willow are two of the most common willows used for medicinal purposes.

The main chemical that gives willow bark its therapeutic effects is salicin. Experts believe that when the body processes salicin, it turns it into salicylic acid, which is the chemical precursor to aspirin. In 1928, European chemists figured out how to extract salicin and turn it into salicylic acid. It became popular as a pain reliever and fever reducer, and was then modified to become acetylsalicylic acid, or aspirin.

Does It Work?

Did You Know?
Willow bark comes in tablet, capsule, powder, and liquid form. A normal daily dose is between 120 to 240 mg of salicin.

Studies show that willow bark can help treat lower back pain and possibly osteoarthritis (OA) pain. One study found that people with back pain who took a high, 240mg dose daily found relief from their pain. Another study showed that willow bark could offer mild pain relief to people with OA. However, there is no evidence that willow bark can lower pain caused by rheumatoid arthritis.

Fewer Side Effects than Aspirin


One of the reasons people use willow bark as an alternative to aspirin is because it doesn’t produce the same side effects as aspirin. Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) can cause stomach irritation or damage, while willow bark taken in normal amounts does not. 

Scientists believe the difference in side effects may be either because the salicylic acid from willow bark is created when the body breaks down salicin (instead of directly entering the body). Another possible explanation is the fact that a standard dose of willow bark comes close to the strength of one baby aspirin.

However, this doesn’t make willow bark completely safe. Willow bark can produce similar side effects to aspirin if it’s taken in high doses for long periods of time. It may also not be safe for people who:

  • use blood thinners
  • have sensitivities or allergies to aspirin
  • have bleeding disorders
  • have kidney disease

Talk to your doctor before you try willow bark to make sure it’s a safe choice for you.

It’s Also an Antioxidant

Willow bark isn’t just good for pain relief. It also contains tannins and flavonoids, which have their own health benefits.

Tannins are chemicals found in many plant-based foods. They’re thought to stop the growth of certain bacteria, viruses, and fungi. They can also improve blood clotting and may boost heart health by helping to lower blood pressure and cholesterol.

Flavonoids are compounds made by plants that give them their red, orange, and yellow colors. They also work as antioxidants in the body, helping cells to repair and protect themselves from damage.

Scientists may discover more uses and benefits for willow bark with future research. For now, the supplement appears to be an effective alternative for people looking to relieve mild back pain or arthritis.