Yes. Randomized trials in overweight adults with knee osteoarthritis show that losing ≥10% of body weight significantly reduces knee pain, joint load and inflammation — and combining diet with exercise works best. Even smaller weight loss helps, but the 10% mark is where mechanical and clinical benefits clearly emerge.
The IDEA trial (PubMed 24065013) — 18-month randomized trial in overweight/obese adults with knee osteoarthritis. Diet-induced weight loss (with or without exercise) significantly reduced knee compressive force and the inflammatory marker IL-6, and improved pain and function scores. The diet + exercise group did best; diet alone beat exercise alone. Weight loss ≥10% was the key factor for better mechanical and clinical outcomes.
Diet + exercise vs. usual care (PubMed 36511925) — after 18 months, the intervention group lost more weight (mean 7.7 kg vs 1.7 kg) and knee pain (WOMAC score) dropped by 0.6 points more than control. The authors noted the clinical meaning of that pain difference needs more study — but the direction is consistent across trials.
Emerging context (PubMed 39476339) — a 68-week trial found a weekly weight-loss medication (semaglutide) plus low-calorie diet guidance reduced body weight by 13.7% and pain scores substantially more than placebo. This is a prescription drug with side effects — relevant mainly for discussing options with a doctor.
Every kilogram of body weight adds multiple kilograms of load across the knee with each step. Reducing load through weight loss lowers joint stress, while reducing inflammatory signals (like IL-6) that contribute to osteoarthritis pain. This is why weight management is a cornerstone of knee-osteoarthritis care.