Overweight and obese people can significantly improve their knee health by losing weight suggests a new US study.
Carried out by the University of California, San Francisco, the team looked at the association between weight loss and the degeneration of their knee cartilage in 640 overweight and obese patients over a 48-month period.
Participants had a minimum body mass index (BMI) of 25 kg/m2, as well as risk factors for osteoarthritis or MRI evidence of mild to moderate osteoarthritis.
For the research patients were categorized into three groups: those who lost more than 10 percent of their body weight, those who lost five to 10 percent of their body weight, and a control group whose weight remained stable.
MRI scans were taken during the study to look at changes in the knee cartilage.
The team found that participants who showed 10 percent weight loss had the lowest rates of cartilage degeneration when compared to the control group.
Participants with 5 percent weight loss also had lower rates of cartilage degeneration, although not as significant as the 10 percent weight loss group.
However, according to lead author Alexandra Gersing, the "most exciting finding" from the study was changes in the menisci, the crescent-shaped fibrocartilage pads that protect and cushion the joint.
"Not only did we see slower degeneration in the articular cartilage," explained Gersing, "we saw that the menisci degenerated a lot slower in overweight and obese individuals who lost more than 5 percent of their body weight, and that the effects were strongest in overweight individuals and in individuals with substantial weight loss."
According to the National Institutes of Health, obesity is a risk factor for osteoarthritis, as carrying extra weight places extra pressure on joints and cartilage, causing them to wear away.
In addition, people with more body fat may have higher levels of inflammation-causing substances in the blood, that can inflame the joints, raising the risk for osteoarthritis.
"Our study emphasizes the importance of individualized therapy strategies and lifestyle interventions in order to prevent structural knee joint degeneration as early as possible in obese and overweight patients at risk for osteoarthritis or with symptomatic osteoarthritis," concluded Dr. Gersing, with light to moderate exercise also recommended to protect against cartilage degeneration in the knee.