Even Minor Weight Loss Can Have Major Effect

According to the results of a study of overweight and obese osteoarthritis (OA) patients, the loss of just 1 lb can have a reduction in knee pressure of 4 lb every time they take a step. The findings suggest that weight loss could slow the progression of OA of the knee.

The study involved 142 overweight and obese patients over age 60 who were diagnosed with knee OA. These patients were placed on weight-loss programs, and their progress was followed over 18 months. By the end of the study, the participants had lost an average of 2% of their body weight and lowered their body mass index by 3%.

The report, which was published in the July 2005 issue of Arthritis & Rheumatism, showed that, for every pound of weight lost, there was a 4-lb reduction in the load on the knee for each step. Stephen P. Messier, PhD, lead researcher, from Wake Forest University, Winston-Salem, NC, said that this accumulated reduction would add up to "more than 4800 lb per mile walked" in a patient's lifetime.

"Although there are no longitudinal studies indicating that weight loss in humans slows the progression of knee OA, a reduction of this magnitude would appear to be clinically relevant," Dr. Messier said. He also said that further research was needed to evaluate the potential of weight loss to slow or even prevent knee OA.