My thanks to Matthew Constantin (ed.)

A writer and biology scientist, Matthew Constantin, PhD, is enthusiastic about new findings that show the beneficial effect of weight loss on the lifestyle of obese people with OA. In his blog Matthew discusses a wide range of weight loss topics, such as weight loss with the balloon procedure, and offers Medifast coupons and a Nutrisystem discount coupon, two medically designed meal replacement programs.

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Osteoarthritis (OA) is the most common form of arthritis in the United States, affecting almost 10% of the population. OA is also the leading cause of chronic disability in this country. Obesity is the one of the strongest risk factors for the development of osteoarthritis, with bilateral affliction of the knee joints being the most common type of OA seen in overweight individuals.

To investigate the effect of weight loss on the symptoms of OA, a meta-analysis was conducted in 2007 that collected the results of prior studies for review. The objective of the meta-analysis was to measure reduction in pain and increase in functionality when overweight patients suffering from knee OA achieved weight loss.

After analyzing the data of the prior randomized controlled trials, the major finding was that a moderate weight reduction regime results in improved functionality and pain reduction for overweight people.

Obesity specialists recommend that overweight individuals aim for a 10% reduction in body weight, using a rate of 1 to 3 pounds per week. However, the meta-analysis found that symptomatic relief began at 5% weight loss. Clinically proven weight loss programs such as Nutrisystem and Medifast can help achieve those targets. Dietary supplements that contain glucosamine sulphate and chondroitin sulfate, have been shown to further help reduce OA symptoms.

The Framingham Heart Study was a comprehensive, longitudinal study conducted in England between the years 1949 and 1985 [ref3]. Data collected from that study showed the following:

If obese men with a body mass index (BMI) greater than 30 lost sufficient weight to be considered merely overweight with a BMI between 26 and 29.9; and if overweight men lost sufficient weight to be considered normal with a BMI under 26; then their chances of developing OA of the knee would be decreased by 21.4%. That percentage would improve if obese men lost enough weight to join the normal weight category.

For women, a parallel drop in weight from obese to overweight, and from overweight to normal, would result in a decrease of 33% of the total rate of osteoarthritis of the knee.

It is well understood how excess weight creates mechanical stress, resulting in osteoarthritis of the knees. Further studies are required to comprehend exactly how obesity causes osteoarthritis of non-weight-bearing joints via secretions from adipose tissue—a tissue which is now recognized as a major endocrine organ.

Nevertheless, it is already clear that being overweight is the single greatest modifiable risk factor for OA. Weight reduction of young people is considered the best course of prevention against later life OA. Weight reduction is the most effective treatment for pain reduction and improved functionality for current obese sufferers of osteoarthritis.

1.  Obesity as a risk factor for osteoarthritis of the hand and wrist: a prospective study. Carman WJ, Sowers MF, Hawthorne VM, Weissfeld LA. Am J Epidemiol 1994;139:119-29
2.  Obesity and osteoarthritis: is leptin the link? Sandell LJ. Arthritis Rheum. 2009 Oct;60(10):2858-60.
3.  Weight and osteoarthritis. Felson DT. J Rheumatol 1995; 22(suppl 43):7-9.

Also of interest may be How to Choose Your Weight Down to the Pound and Obesity And Osteoarthritis: How Strong Is The Connection?