Studies Spotlight Diet, Supplements for Knee Pain

Fiber helps lower cholesterol, stabilize blood sugar levels and keep the bowels running smoothly, but a new study suggests it can also reduce knee pain from arthritis.

Researchers found that people who ate the most fiber reported reduced osteoarthritis knee pain by up to 60%. However, X-rays did not show any difference in their knees compared to those who consume less fiber.

A second study looked at the effects of the dietary supplement chondroitin on knee pain. That study – sponsored by a maker of the supplements – found that taking chondroitin daily was linked to less knee pain and improved function.

Both studies were published online May 23 in the Annals of the Rheumatic Diseases.

“With both of these studies, the danger is that people are thinking they’re making a change in their arthritis, but they may only be masking the pain. Neither study has proven a change in the natural history of osteoarthritis,” explained Dr. Victor Khabie, who was not involved with the studies. He is co-director of the Orthopedic and Spine Institute at Northern Westchester Hospital, in Mount Kisco, N.Y.

Lead researchers Zhaoli Dai, a postdoctoral researcher at Boston University, said, “There is a strong link among obesity, inflammation and painful knee osteoarthritis. We speculate that eating more fiber increases satiety and therefore reduces total caloric intake and reduces body weight.”

The second study looked at chondroitin sulfate. It’s a chemical found naturally in the cartilage of the knee, according to the U.S. National Library of Medicine. Reductions in pain and improvements in joint function were greater in people treated with chondroitin or celecoxib at three and six months. The researchers said that chondroitin provided similar relief to celecoxib.

Khabie said, “It looks like there’s an anti-inflammatory or pain-relieving effect when chondroitin is taken in a very purified, very well-controlled state, but that’s probably not what’s available off-the-shelf [in the United States].” He noted that chondroitin is a supplement, and in the United States supplements aren’t regulated in the same way that drugs are.



Khabie also said that the safety of taking chondroitin long-term isn’t known.

My Take:
In the first study, the reduction of inflammation from fiber is creating the pain reduction. When the LDL cholesterol drops from increased fiber, it is because tissue inflammation has been reduced. Reducing systemic inflammation will reduce the pain associated with osteoarthritis of the knee. Of course, it’s not a cure. You have to restore circulation to the bones of the knee to actually reverse osteoarthritis and see improvement on X-ray. Fiber won’t do that, but I suspect chondroitin will, if the related biochemistry is balanced.

In the second study, I believe that the joint is actually healing, despite the lack of X-ray changes. Chondroitin sulfate is the building block of connective tissue – muscle, ligament, tendon, bone and cartilage. It has no direct anti-inflammatory effect. However, rebuilding a joint with chondroitin sulfate depends on two chemical pathways – GAGS synthesis (sulfur amino-acid metabolism) and glucose metabolism. Both of these pathways are impaired in a majority of the population.

The Bottom Line:
Chondroitin sulfate was the first supplement I recommended over 35 years ago. At the time, it was effective in treating about 80% of my low back cases and started me on my path with nutrition. I soon realized that half of the cases that did not respond were diabetic, although I didn’t understand the chemistry at the time. The other half had GAGS synthesis issues that I would learn about many years later.

Today, chondroitin sulfate has limited application as such a large percentage of our population has aspects of metabolic syndrome. What a change in a single generation!

Source: May 24, 2017 National Institutes of Health