Updated October 13, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: For an overweight dog with arthritis, the most helpful diet change is losing weight, which can noticeably reduce lameness. Beyond that, therapeutic joint diets with high levels of omega-3 fatty acids (EPA and DHA) have good evidence for improving arthritis signs. Supplements like glucosamine have mixed evidence. Any diet should be complete and balanced, and weight loss should be planned with your vet.
Weight loss first
- Extra fat adds load and inflammation to sore joints.
- Studies show weight loss alone can improve lameness in overweight dogs with arthritis.
- Your vet can calculate a target weight and calorie plan. Prescription weight-loss diets keep dogs fuller while cutting calories safely.
- Measure food, and count treats.
Joint diets
Prescription and therapeutic joint diets contain high levels of fish-derived omega-3 fatty acids. Controlled studies found these diets improved weight bearing and mobility in dogs with arthritis, and some dogs could reduce their pain medication dose.
Supplements
- Omega-3 fatty acids (fish oil): the best-supported supplement. Your vet can recommend a product and amount.
- Green-lipped mussel: some evidence of benefit.
- Glucosamine and chondroitin: results are mixed. Some dogs seem to benefit.
- Turmeric and other herbal products: limited evidence in dogs.
Look for products with a National Animal Supplement Council (NASC) seal, and tell your vet about any supplement.
What to avoid
- Fatty table scraps and high-calorie treats.
- Human joint supplements that may contain xylitol or unsafe ingredients.
- Crash diets without veterinary guidance.
See also: arthritis treatment options.
Sources
- Kealy RD, et al. Effects of diet restriction on life span and age-related changes in dogs. JAVMA. 2002
- Roush JK, et al. Multicenter veterinary practice assessment of the effects of omega-3 fatty acids on osteoarthritis in dogs. JAVMA. 2010
- Roush JK, et al. Evaluation of the effects of dietary supplementation with fish oil omega-3 fatty acids on weight bearing in dogs with osteoarthritis. JAVMA. 2010
- Impellizeri JA, et al. Effect of weight reduction on clinical signs of lameness in dogs with hip osteoarthritis. JAVMA. 2000
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.