High-fat, high-carb diet linked to arthritis. In case you need another reason to put down the junk food, researchers in Australia have discovered that a diet loaded with saturated fats is a key factor in the development of arthritis. While many of us associate diets full of fatty foods with heart disease, high cholesterol, and obesity, it turns out they also play a role in bone health as well. Researchers found that simple sugars and saturated fats actually weaken cartilage and affect the bone under the cartilage too.