Fiber Supplement Reduces Knee Arthritis Pain and Improves Strength

A daily prebiotic fiber supplement significantly reduced knee osteoarthritis pain and improved physical function in a recent clinical trial. Participants taking the supplement also showed increased grip strength and reduced pain sensitivity. This research suggests a connection between gut health, muscle function, and pain perception.

Researchers at the University of Nottingham conducted the INSPIRE clinical trial. They investigated inulin, a natural dietary fiber found in various vegetables. The study found that daily inulin intake substantially decreased pain among individuals with osteoarthritis.

The findings were published in the journal *Nutrients*. They indicate that supporting gut health could offer a new approach to managing knee osteoarthritis. This condition is a widespread cause of chronic pain and disability, particularly in older adults.

Inulin functions as a prebiotic, nourishing beneficial gut bacteria. These bacteria produce short-chain fatty acids, such as butyrate, which can influence inflammation and pain pathways. Participants receiving inulin had higher levels of butyrate and glucagon-like peptide-1 (GLP-1), a gut hormone linked to pain regulation and muscle health. Elevated GLP-1 levels correlated with improved grip strength.

The six-week randomized controlled trial involved 117 adults with knee osteoarthritis. Participants were divided into four groups: inulin alone, digital physiotherapy-supported exercise (PSE) alone, both treatments, or a placebo. Both inulin and physiotherapy independently reduced knee pain. However, only the inulin group experienced enhanced grip strength and lower pain sensitivity. The inulin group also had a significantly lower dropout rate, at 3.6%, compared to 21% in the physiotherapy group. This suggests that a daily supplement may be easier for patients to adhere to than an exercise program.