Osteoarthritis and Weight

There are many risk factors for OA, including age, genetics, gender and injury to the joint (e.g., due to sports or accidents). In addition, several studies link the disease with excess weight. ¹

Excess Weight and Osteoarthritis
The research has shown the strongest link between overweight or obesity and knee OA. Results from a study published in the Journal of Rheumatology found a 9- to 13-percent increased risk for the development of the disease with each kilogram increase in body weight. ² That means that gaining 10 pounds would result in an increased risk of 40 to 59 percent. Being overweight during the early adult years can also increase the risk of developing the disease later on. For example, a longitudinal study of 1,180 men, who did not have knee OA between the ages of 20 to 29, found that the heaviest participants (BMI of 24.7 to 37.6) were three times more likely to develop knee OA by age 65, as compared to their thinner counterparts (BMI of 15.6 to 22.8). ³

While it remains unclear exactly how excess weight influences OA, it most likely can be explained by the load it places on the joints. Each 1-pound increase in weight translates to a 2- to 3-pound increase in the overall force on the knee. ⁴ This increases the stress on the joints and can accelerate the breakdown of cartilage.

Weight loss can help.
The good news is that losing weight can help. According to data from the Framingham Knee Osteoarthritis study, women who lost an average of 11 pounds reduced their risk for developing OA by 50 percent. ⁵ Losing a modest amount of weight (around 10 percent) may help to slow its progression and has been shown to substantially reduce symptoms of knee pain and improve quality of life. ^6,7

Exercise may also help. While a limited number of studies have been done in this area, preliminary research suggests that moderate exercise and strength training may help reduce knee pain and improve physical function. ^8,9

Bottom Line: Maintaining a healthy body weight or losing even a modest amount of weight can go a long way in preventing and/or treating OA.

This content is reviewed regularly. Last updated December 17, 2011.

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Other Science Library topics:

Body Weight and Diabetes

Body Weight and Cancer

¹ Symmons D, Mathers Colin, Pfleger B. Global Burden of Osteoarthritis in the Year 2000. Global Burden of Disease 2000.

² Cicuttini FM, Baker JR, Spector TD. The association of obesity with osteoarthritis of the hand and knee in women: a twin study. J Rheumatol. 1996;23:1221-6.

³ Gelber AC, Hochberg MC, Mead LA, Wang NY, Wigley FM, Klag MJ. Body mass index in young men and the risk of subsequent knee and hip osteoarthritis. The American Journal of Medicine. 1999 Dec;107(6):542-548.

⁴ Felson et al. Osteoarthritis: new insights. Part 1: the disease and its risk factors. Ann Intern Med. 2000 Oct 17;133(8):635-46. Review.

⁵ Felson DT, Zhang Y, Anthony JM, et al. Weight loss reduces the risk for symptomatic knee osteoarthritis in women. The Framingham Study. Ann Intern Med. 1992;116:535-9.

⁶ Rjeski WJ, Focht BC, Messier SP, et al. Obese, older adults with knee osteoarthritis: weight loss, exercise, and quality of life. Health Psychol. 2002;21:419-26.

⁷ Christensen R, Astrup A, Bliddal H. Weight loss: the treatment of choice for knee osteoarthritis? A randomized trial. Osteoarthritis Cartilage. 2005;13:20-27.

⁸ Ettinger WH, Burns R, Messier SP, Applegate W, Rejeski WJ, Morgan T, Shumaker S, Berry MJ, O'Toole M, Monu J, Craven T. A randomized trial comparing aerobic exercise and resistance exercise with a health education program in older adults with knee osteoarthritis: the Fitness Arthritis and Seniors Trial. JAMA. 1997 January 1;277(1):25-31.

⁹ Messier SP, Loeser RF, Miller GD, Morgan TM, Rejeski WJ, Sevick MA, Ettinger WH, Paho M, Williamson JD. Exercise and dietary weight loss in overweight and obese older adults with knee osteoarthritis: the Arthritis, Diet, and Activity Promotion Trial. Arthritis Rheum. 2004;50:1501-1510.