Most people with bad knees have tried something. Painkillers, a brace, maybe an exercise video that mostly lives on the fridge. Few would guess the next idea starts in a kitchen cupboard.
A six-week trial from the University of Nottingham tested 20 grams a day of inulin, a soluble fiber found in chicory root and Jerusalem artichokes. The researchers found it cut knee arthritis pain in adults with the condition.
The results appeared in the journal Nutrients and were reported on October 27, 2026.
The trial, called INSPIRE, randomly placed 117 adults with diagnosed knee osteoarthritis into one of four groups. One took the inulin powder. One did digital physiotherapy-supported exercise. One did both. The last group got a placebo.
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Both inulin and the exercise program eased knee pain on their own. But only the inulin group also showed better grip strength and lower pain sensitivity. People stuck with the powder more easily, too.
About 3.6 percent of the fiber group dropped out, against 21 percent of the exercise-only group.
Why gut bacteria may ease a sore knee
The researchers think the fiber is not acting on the knee at all. Gut bacteria ferment inulin and release short-chain fatty acids, especially butyrate, which calms inflammation and shifts how the body processes pain.
People on inulin also had higher levels of glucagon-like peptide-1, known as GLP-1. That is a gut hormone that controls blood sugar, appetite and, it now seems, pain and muscle function.
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GLP-1 is the same pathway targeted by semaglutide, the active ingredient in Novo Nordisk's Ozempic and Wegovy. In the trial, higher GLP-1 levels tracked with better grip strength.
The Nottingham team calls this a gut-muscle-pain axis. It is a new angle on an old disease and the main reason the finding has drawn attention.
What a single six-week trial can and cannot say
Knee osteoarthritis is the most common form of arthritis. It affects tens of millions of adults in the United States, and no simple drug or diet has reliably held back the pain over the long run.
This is one trial. One site, 117 people, six weeks. Larger and longer studies are needed to confirm the effect, see how long it lasts and show which patients benefit most.
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Inulin itself is widely sold as a powder and is naturally found in foods such as chicory root, Jerusalem artichokes, onions, garlic and leeks. The trial dose was 20 grams a day, well above what most people get from food alone, and higher amounts can cause bloating or gas.
Anyone with knee arthritis who wants to try adding more fiber should talk to a doctor first, especially if they take other medications or have a gut condition.
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This article is made and published by Mie Hermansen, who may have used AI in the preparation.