192 obese [body mass index (BMI) > 30 kg/m2] patients (>50 years old) with primary symptomatic knee osteoarthritis (OA) were randomized to be placed on special dietary restrictions, one consisting of very low energy diet (415 kcal/day) or low energy diet (810 kcal/day) for a period of 8 weeks followed further by 8 weeks of 1200 kcal/day diet. At 16 week intervention period, there was a clear overall reduction in pain with both low-energy diets, but there no clinically significant difference between very-low energy diet (VLED) and low-energy diet (LED).