Eating a lot of foods high in saturated fat and carbohydrate may increase the risk of developing osteoarthritis, according to an Australian study.
Researchers at Queensland University of Technology (QUT) and the University of Southern Queensland investigated the association between osteoarthritis and common dietary fatty acids.
They studied the effects on joints of diets rich in a variety of saturated fatty acids found in such foods as butter, coconut oil, palm oil and animal fat, and simple carbohydrates — in other words, a high-fat, high-carbohydrate diet common to “junk food”.
The study revealed changes in the composition of cartilage, particularly in the weight-bearing joints of the hip and knee.
“Our findings suggest that it’s not wear and tear but diet that has a lot to do with the onset of osteoarthritis,” said Professor Yin Xiao from QUT’s Institute of Health and Biomedical Innovation.
A diet containing simple carbohydrates together with 20% saturated fats produced osteoarthritic-like changes in the knee. Saturated fatty acid deposits accumulate in the cartilage, changing its metabolism and weakening the cartilage, making it more prone to damage.
This, in turn, leads to osteoarthritic pain due to the cushioning effect of the cartilage being lost. At the same time, the bone itself is also adversely affected.
As part of the study, the team replaced the meat fat in the diet with lauric acid, a saturated fatty acid found in coconut oil. This was associated with decreased signs of cartilage deterioration and metabolic syndrome, suggesting that it had a protective effect.
Commenting on the findings, Dr Natalie Carter, head of research liaison and evaluation at Arthritis Research UK, said: “This study supports our advice that a diet that is low in saturated fats can help the ten million people in the UK who have arthritis. We also know that vitamins and minerals such as calcium, vitamin D and iron are important for maintaining healthy joints and bones.”