Could this natural fiber be a new way to tackle knee pain? Researchers put it to the test

Stiff, painful knees on the stairs are a familiar complaint after 50. The usual advice is to keep moving and strengthen the muscles around the joints. But researchers at the University of Nottingham wanted to explore another possibility: could something as simple as a type of dietary fiber help?

Their six-week study involved 117 adults with knee osteoarthritis. The researchers tested a daily fiber supplement, an exercise program, and a combination of the two. The results offered an intriguing lead.

What did the study find?

Published in the journal Nutrients, the study split participants into four groups. They received a fiber supplement, a placebo, a digital exercise program, or both the supplement and exercise.

After six weeks, both the supplement and exercise groups reported less knee pain than the placebo group. The exercise group saw a slightly larger improvement in pain scores.

People taking the supplement also showed improvements in grip strength and became less sensitive to pressure that could cause pain. Meanwhile, those following the exercise program improved at everyday movements, including standing up from a chair.

There was another interesting difference: just 3.6% of people in the supplement-only group dropped out, compared with 21% in the exercise-only group. Taking a daily supplement may have been easier to stick with, but that doesn't mean it worked better than exercise.

What does the gut have to do with knee pain?

The fiber researchers tested is called inulin. It occurs naturally in chicory root and helps feed the beneficial bacteria living in your gut.

These bacteria break down inulin and produce substances that may help regulate inflammation in the body. Because inflammation can contribute to joint pain, researchers are investigating whether the gut could play a role in how people experience osteoarthritis.

The team also found changes in a hormone called GLP-1, which is produced in the gut and helps regulate several bodily processes. However, the study couldn't prove that these changes were responsible for the improvements in pain.

The connection is promising, but scientists still have a lot to learn about how it works.

Can you get this fiber from food?

Inulin is naturally present in chicory root, Jerusalem artichokes, onions, garlic and asparagus. It's also added to some foods and sold as a dietary supplement.

However, the study used a specific supplement at a daily dose of 20 grams. Simply eating more of these foods hasn't been shown to have the same effect.

Taking inulin can also cause gas, bloating or stomach discomfort, particularly if you increase your intake quickly. The Cleveland Clinic explains these possible side effects. If you're considering a supplement, speak to your doctor or a registered dietitian first.

Should you try it for knee pain?

Not just yet based on this study alone. It involved only 117 people and lasted six weeks, so larger studies are needed to find out whether the benefits last and who might benefit most.

Exercise remains one of the main ways to manage knee osteoarthritis. The UK's National Institute for Health and Care Excellence recommends tailored exercise to help relieve symptoms and improve movement. The US Centers for Disease Control and Prevention also recommends physical activity to help manage arthritis.

For now, inulin is an interesting possibility, not a proven replacement for treatment. If knee pain is affecting your daily life, talk to your doctor or physiotherapist before making changes to your care.