Grape consumption may help alleviate the pain of knee osteoarthritis, improve joint flexibility and overall mobility, a study by Texas Woman’s University finds.

Grapes may ease osteoarthritis painIn the 16-week study led by Shanil Juma, assistant professor in nutrition and food sciences, 72 men and women with the condition consumed either a whole grape freeze-dried powder or a placebo powder. Juma presented its findings in San Diego at the Experimental Biology conference, April 26-30.

The study, which received funding from the Fresno-based California Table Grape Commission, found men and women consuming the grape powder had a significant decrease in activity-related pain and an overall drop in knee symptoms. The effect was stronger in women.

Age-related differences included a 70% increase in “very hard activity” for those under age 64 consuming the grape powder, while those getting the placebo reported a significant decrease. Participants over age 65 in both groups reported a decline in moderate to hard activities.

Researchers observed increased cartilage metabolism in men consuming the grape powder. The effect was not seen in women. The serum marker for inflammation measured was increased in both placebo and grape groups, but less so in the grape group.

“These findings provide promising data that links grape consumption to two very important outcomes for those living with knee osteoarthritis: reduced pain and improvements in joint flexibility,” Juma said in a news release. “More research is needed to understand the results of the serum biomarkers, as well as the age and gender differences observed.”

At the conference, Juma also shared results from a cell study examining the effects of whole grape polyphenols on cartilage cell integrity and markers of cartilage health.

Cartilage cells were first treated with various doses of whole grape polyphenols, and then stimulated with an inflammatory agent. Cell proliferation significantly increased — varying by dose — in the grape polyphenol treated cells with the agent. Moreover, a marker for cartilage degradation was significantly lower with the three highest doses of the whole grape polyphenols compared to control cells and cells treated with the inflammatory agent. That suggests a possible protective effect of grapes on cartilage cells.

Osteoarthritis involves cartilage loss between joints. It’s more likely to occur in people more that 45 years old, and women are more susceptible than men.

The Experimental Biology conference is a scientific meeting focused on research and life sciences and covers fields including anatomy, biochemistry, nutrition, pathology and pharmacology. It’s comprised of nearly 14,000 scientists and exhibitors.