Pain Caused by Arthritis Can Be Diminished through Weight Loss

Obese adults who lose as much as 10 percent of their body weight may also significantly reduce their knee pain caused by arthritis, according to USA Today.

About 250 million people worldwide have knee osteoarthritis, which is the leading cause of disability in older adults, says lead author Stephen Messier, a professor of health and exercise science at Wake Forest University in Winston-Salem, N.C. It can lead to loss of mobility and diminished quality of life, he says. "Mobility is critical to being able to grow old independently."

Osteoarthritis is a chronic condition characterized by the breakdown of the joint's cartilage, according to the Arthritis Foundation. Cartilage is the part of the joint that cushions the ends of the bones and allows easy movement of joints. The breakdown of cartilage causes the bones to rub against each other, causing stiffness, pain and loss of movement in the joint.

Obesity is a major risk factor for knee osteoarthritis, Messier says. There are two possible pathways to knee osteoarthritis. One is biomechanical, which means the load on the joint has an effect on the knee, and the other is an increase in inflammation, which can affect muscle function and sensitivity to nerve endings, which increases pain, he says. "What we found was both pathways were affected by weight loss."

A 10% weight loss "can help people with knee osteoarthritis who are overweight or obese maintain their independence and have a good quality of life for the long term," he says. Messier and colleagues recruited 454 overweight and obese adults with osteoarthritis in their knees. They reported having pain in their knees most days of the week. All were 55 or older and considered sedentary. For the 18-month study, participants were assigned to one of three groups: a diet-and-exercise plan; a diet-only plan or an exercise-only program.