Scientists have found a link between consumption of animal fats and an increased risk of osteoarthritis. In the first study of its kind, researchers in Australia, found that unsaturated fat changes the composition of cartilage, particularly in the weight-bearing joints of the hip and knee.
The collaborative study was conducted by Professor Yin Xiao, from Queensland University of Technology’s Institute of Health and Biomedical Innovation and his team, and Professor Lindsay Brown and his team at the University of Southern Queensland.
The disease can affect any joint in the body but most often it affects the knees, hips, hands, and spine.
Osteoarthritis is the most common form of arthritis, affecting millions across the globe.
The condition can affect any joint in the body but it is commonly found in the knees, hips, hands, and spine.
In osteoarthritis, the cartilage – which acts as a buffer between joints – slowly breaks down. With the degeneration of the cartilage, joints become stiff, swollen, and painful. The condition tends to worsen over time.
Osteoarthritis commonly affects women and older adults. Bone deformities and joint injuries suffered in the past also increase the chances of developing the condition.
Obesity is another risk factor for osteoarthritis. This is partly because the extra weight puts more stress on the joints. But the link between obesity and osteoarthritis may be a little deeper than that.
For their study, the researchers investigated the effects on joints of diets rich in an assortment of saturated fatty acids found in butter, animal fat, coconut oil, palm oil, and simple carbohydrates – a high-fat, high carbohydrate diet common to so called “junk food.”
The study shows that osteoarthritis may be less to do with the general usage of our joints and more to do with our regular diet. As Prof. Xiao says:
“Our findings suggest that it’s not wear and tear but diet that has a lot to do with the onset of osteoarthritis.”
The researchers tested a variety of saturated fats and found that long term use of animal fat, butter and palm oil was the most damaging to cartilage. There was less damage caused by lauric acid, a saturated fatty acid found in coconut oil.
According to their results, a diet containing 20 percent saturated fats and simple carbohydrates “produced osteoarthritic-like changes in the knee.”
“Saturated fatty acid deposits in the cartilage change its metabolism and weaken the cartilage, making it more prone to damage. This would, in turn, lead to osteoarthritic pain from the loss of the cushioning effect of cartilage. We also found changes in the bone under the cartilage on a diet rich in saturated fat.”
Long-term use of animal fat, butter, and palm oil all appeared to weaken cartilage. However, when they substituted animal fat with lauric acid – a saturated fat naturally found in coconut oil – the opposite effect was observed. Lauric acid appeared to be beneficial.
“When [the researchers] replaced the meat fat in the diet with lauric acid, [they] found decreased signs of cartilage deterioration and metabolic syndrome, so it seems to have a protective effect,” says Ph.D. student Sunder Sekar, who was also involved in the study.
The researchers conclude:
“Replacement of traditional diets containing coconut-derived lauric acid with palm oil-derived palmitic acid or animal fat-derived stearic acid has the potential to worsen the development of both metabolic syndrome and osteoarthritis.”
This study followed on from Prof. Xiao’s earlier work, which revealed that antioxidants and anti-cholesterol drugs could slow the progression of joint damage caused by fatty acids found in palm oil and butter.
The study was published in the journal Scientific Reports.