Diets with lots of saturated fat and simple carbohydrates — meat and sweets — may do even more damage than we've suspected. Not only do saturated fats and refined carbohydrates increase the risk of heart disease, stroke, some forms of cancer and overall inflammation in the body, they can bring on osteoarthritis, a recent study has found.

Researchers from two Australian universities looked at the effect of a diet rich in a variety of saturated fatty acids had on joint health. They found saturated fat weakened the cartilage in joints, especially in the weight-bearing hip and knee joints.

The cartilage in your joints seals the ends of the bones and acts as a shock absorber during weight-bearing activities like running or walking. Though it is often assumed that osteoarthritis is the result of wear and tear on joints, researcher Yin Xiao of Queensland University of Technology says diet has a lot to do with the onset of the painful disease.

Saturated fat weakens the cartilage in joints, especially in the weight-bearing hip and knee joints.

The study examined the effect of diets high in different types of saturated fats — butter, coconut oil, palm oil and animal fats — combined with simple carbohydrates to see how such a diet might affect joints.

A diet containing simple carbohydrates — like candy, table sugar, cookies, pastries and soft drinks — combined with 20 percent of calories from saturated fats caused osteoarthritic-like changes in the knee joint, the study found. Deposits of saturated fatty acids in the cartilage changed its metabolism and weakened the cartilage, making joints susceptible to damage and the resulting pain from the loss of cushion.

A variety of saturated fats were tested, including animal fat, butter, and palm oil. Long-term use of these fats had a negative effect on cartilage. Lauric acid, a saturated fat found in coconut oil, was used to replace meat fat in some diets, and it appeared to have a protective effect on cartilage.

You can reduce your risk of developing osteoarthritis by maintaining a healthy diet and being physically active. Focus on eating lean sources of protein, plenty of fruits, vegetables, whole grains and low-fat dairy products. Just 30 minutes of physical activity performed five days a week can keep your joints limber and strengthen the muscles that support susceptible joints like hips and knees.

The study is published in Scientific Reports.