Diet

While no specific diet has been shown to cause osteoarthritis, some research has suggested that a diet rich in some nutrients might reduce the risk of OA or its progression. But research is far from conclusive.

One of the most studied nutrients is vitamin E. As far back as 1996, data from the Framingham study showed that men with the highest intake of vitamin E were 30 percent less likely to have progression of knee OA.  Subsequent research out of Australia, however, found no effect of vitamin E on the radiographic progression or symptoms of OA over two years.

In the Johnson County Osteoarthritis Project, the first racially balanced, population-based study of OA in whites and blacks, Joanne Jordan, MD, of the University of North Carolina at Chapel Hill’s Thurston Arthritis Research Center looked at serum levels of a form of vitamin E called alpha tocopherol and found no association with knee OA; however, a higher ratio of alpha to gamma tocopherol, another form of vitamin E, was associated with a 50 percent less likelihood of having knee OA.

So far no studies show that changing your diet will prevent OA or its progression – except as it relates to weight loss, says Dr. Jordan. Being overweight is a known risk factor for OA. “The most important advice is to maintain a healthy weight,” she says.

High-heel Shoes

If you want to protect your knees from damage, a recent study suggests you limit wearing high heels to special occasions.

In a study published in the March 2012 issue of Gait and Posture, researchers in the University of Iowa’s kinesiology department had 15 women walk in selected three heel heights –  flat, two inches, and 3.5 inches – and had at both a preferred (self-selected) speed and at a fixed speed.  The researchers then used motion analysis and the use of a force platform to estimate the forces on the knee. “In other words, we use cameras and reflective markers to measure certain body locations (joints, etc.) and that provide us with movement data during walking,” says Danielle Barkema, who led the study.  “We also are collecting the forces of the body by having subjects step onto a force platform. We combine motion and force data to calculate the forces of the knee joint.”

The researchers found that height of the heels changed the women’s walking characteristics such as speed and stride length. As the heel height increased, they also saw an increase in compression on the medial, or inside, of the knee. “Higher medial loads at the knee are thought to be associated with joint degeneration and medial compartment knee osteoarthritis,” says Barkema, who is now a Senior Research Coordinator in the Medical School at Northwestern University. “We did see a systematic increase in the internal knee abduction with an increase in heel height.  This occurred in both preferred and fixed walking speeds.

“Therefore,” she says, “continually creating this loading by wearing high heels consistently over a period of time may put individuals at risk to develop knee OA.  Our results suggest that the higher the heel – at least up until 3.5 inches – the worse the medial compartment loading becomes.”

While the study does not show that wearing high heels will cause knee OA, its results suggest that wearing high heels, especially higher heels, may put individuals at greater risk for knee OA, says Barkema.

High-impact Exercise

While exercise is a good thing for people with OA, research shows that middle-aged people who participate in high-impact, weight bearing exercise may cause damage to their knees that leads to osteoarthritis. In a study of 136 women and 100 men aged 45 to 55, researchers at the University of California San Francisco found that MRIs were more likely to show lesions of the cartilage, menisca and ligaments in those who reported high levels of physical activity compared to those with lower levels of activity.

Other research has shown that bursts of unaccustomed exercise or exercising without proper warm up can lead to injuries that predispose people to osteoarthritis years down the road.

The message, researchers say, is to stick with lower impact exercises when possible, to warm up before exercise and try to maintain level of activity all week, rather than being a weekend warrior.