Osteoarthritis is an inflammatory condition that affects the joints. It is the most common form of arthritis worldwide and is a major contributor to disability among older adults. The findings of a recent study suggest that curcumin reduces pain associated with osteoarthritis of the knee.

Curcumin in an antioxidant compound produced by the plant Curcuma longa, a member of the ginger family. Curcumin exhibits a wide array of beneficial health effects, including anti-inflammatory, anti-cancer, and anti-diabetes properties. It is responsible for the bright yellow pigment of turmeric, a type of spice commonly used in Indian food.

The randomized, double-blind, placebo-controlled trial involved 70 adults over the age of 40 years who had osteoarthritic knee pain and effusion synovitis, an indicator of inflammatory activity in the joint. Half of the participants took 1,000 milligrams of curcumin (in capsule form) daily for 12 weeks. The remaining participants took a placebo. The authors of the study measured the participants' knee pain using a visual analogue scale, which gauges a person’s pain on a 100-millimeter spectrum. They also assessed their effusion–synovitis volume via magnetic resonance imaging (MRI) and noted changes in the participants' knee function.

At the end of the 12-week study, the pain levels among the participants' who took the curcumin dropped nearly 24 millimeters on the visual analog scale. Pain levels among those who took the placebo only dropped 15 millimeters. The participants who took the curcumin also showed improvements in their knee function. The MRI data showed no changes in the participants' effusion-synovitis, however.

These findings suggest that curcumin reduces pain and improves function in people who have osteoarthritis. The sample size and short duration of this study may have implications for its clinical applications, however. Larger, longer studies are needed to confirm these findings.

• Link to study abstract.