Is Weight Loss A Preventive Measure For Osteoarthritis (OA)?
Is Weight Loss A Preventive Measure For Osteoarthritis (OA)?
The constantly growing rate of overweight people over the last decade has seen a corresponding increase in the occurrence of Osteoarthritis (OA). Over 70% of people aged 65 years and above are now affected by OA. Studies have demonstrated that overweight and obese people are at a much higher risk of developing OA, especially arthritis of the knee.
How Is OA Induced By Obesity?
Of the several theories that have been put forth to explain the link between obesity 
and OA, two are the most popular. The first is that overweight individuals have abnormally high body weight that their joints must support. The higher load induces excessive wear-and-tear of cartilage, which causes OA.
However, just load exerted on a joint is unlikely to be the only cause of OA, as suggested by the fact that obesity causes an increased risk for hand OA. The hand is not a load-bearing joint, so it shouldn’t be at increased risk of OA if weight is the sole causal factor. However, being overweight is definitely one of the contributing factors, because obesity increases risk of OA for load-bearing joints like knees more than it does for hands.
The second theory hypothesizes that overweight individuals have some factor that circulates through the body, which affects joints. Such a phenomenon would explain the higher occurrence of OA even in non weight-bearing joints such as hands or neck, in obese individuals.
Some recent studies have found evidence in support of this second theory. Adipose tissue, in addition to performing the function of energy storage, also acts as an endocrine organ. Adipose cells are capable of secreting substances that induce inflammation. These bioactive substances circulate through the bloodstream and affect joints anywhere in the body.
For instance, the constant low-grade inflammation seen in many obese individuals is actually the result of the TNF-alpha and leptin generated by the peptides found in adipose tissue [1]. It has been hypothesized that the chronic inflammation may have adverse effects on cartilage, which may eventually lead to OA.
Can Weight Loss Reduce the Symptoms of OA?
In 2007, researchers conducted a review study of all studies that had so far examined OA and weight. The review assessed whether weight loss would reduce pain and functional disability in patients with knee OA. The meta-analysis discovered that physical disabilities of overweight knee OA patients reduced upon moderate weight reduction.
The review concluded that significant relief from OA symptoms is possible through a 5–10% reduction in weight. Weight loss programs like Medifast or Nutrisystem achieve a moderate weight loss of about 3lbs per week. This, in conjunction with proven pain relief arthritis supplements such as Eazol and Joint Kote, can bring symptomatic relief to people with OA.
What Is The Effect Of Weight Loss On OA?
Studies on OA and weight loss have found that a reduction in BMI brings about a considerable improvement in the symptoms of OA [3]. Specifically, in these studies knee OA risk diminished by a significant 21.4% in obese men (BMI>30) who lowered their BMI to the level of 26-29.9, as well as overweight men (BMI>26) who reduced their BMI to below 26. It follows logically that reduction in OA risk would be even greater if obese men lowered their BMI even further.
In the case of female subjects, the incidence of knee OA decreased by an astonishing 33% for obese women moving from the obese to the overweight category, and overweight women going from the overweight to the normal category.
Epilogue
Many unanswered questions on how obesity and OA are interrelated on a physiological level remain unanswered. What’s clear though is that there is a definite correlation between being overweight and an increased OA risk for knees, as well as hands and hips. Unequivocally, reduced OA symptoms have been clearly observed upon weight loss. Therefore, it follows that weight reduction should be a part of OA treatment. Furthermore, since obesity during youth has been found to increase risk of OA in later life, preventive measures to avoid and cure obesity are important.
About The Author
A scientist with an interest in the relationship between obesity and joint diseases, Matthew Dinnos, closely follows the relevant ongoing research. Denos runs a blog where he evaluates various weight loss programs and offers Medifast online coupons $50 and a promotion code for Nutrisystem, two clinically studied diets available in the US.
References
1. Obesity and osteoarthritis: is leptin the link? Sandell LJ. Arthritis Rheum. 2009 Oct;60(10):2858-60.
2. Effect of weight reduction in obese patients diagnosed with knee osteoarthritis: a systematic review and meta-analysis. Ann Rheum Dis. 2007 Apr;66(4):433-9. Epub 2007 Jan 4. Christensen R, Bartels EM, Astrup A, Bliddal H.
3. Comparing two low-energy diets for the treatment of knee osteoarthritis symptoms in obese patients: a pragmatic randomized clinical trial. Riecke BF, Christensen R, Christensen P, Leeds AR, Boesen M, Lohmander LS, Astrup A, Bliddal H. Osteoarthritis Cartilage. 2010 Feb 17.
