Efficacy of a Very-Low-Calorie Weight Loss Diet Plus Exercise Compared With Exercise Alone on Hip Osteoarthritis Pain : A Randomized Controlled Trial.

Researchers wanted to know whether adding a weight loss diet to exercise would reduce hip pain more than exercise alone in people living with hip osteoarthritis who were overweight or obese. Over 100 adults were randomly assigned to either a home exercise program delivered by telehealth, or the same exercise program plus a very-low-calorie diet also delivered by telehealth. After 6 months, the diet-plus-exercise group lost about 8.5% more weight than the exercise-only group, but this extra weight loss did not translate into greater pain relief.

By 12 months, the picture became more mixed: the diet-plus-exercise group showed better improvements in body weight, disability scores, and overall hip function, though quality of life and physical activity levels were similar between groups. The study suggests that while combining diet and exercise produces better weight loss and some functional gains, the primary goal of reducing hip pain itself may be achievable through exercise alone.

This study tested whether adding a strict weight loss diet to an exercise program would reduce hip pain better than doing exercise by itself. Both groups followed a home exercise program over 6 months, but one group also followed a very-low-calorie diet.

After 6 months, the people who did both diet and exercise lost more weight, but their hip pain improved about the same amount as those who only exercised. By one year, the combined approach did lead to more weight loss and people reported less hip disability in daily tasks, but surprisingly this did not mean their quality of life improved more or that they moved around more.

The good news is that exercise alone appeared quite effective for pain relief, and neither group experienced serious problems from the treatment.

This is a summary of research, not medical advice. Talk to your own healthcare provider about anything affecting your care.

This RCT examined a clinically relevant question: whether the addition of a very-low-calorie diet enhances the pain-reduction benefits of exercise in hip osteoarthritis. The primary outcome showed no significant between-group difference in pain severity at 6 months despite substantially greater weight loss in the combined group (mean difference 0.6 units favoring VLCD plus exercise, with confidence intervals crossing zero).

Secondary outcomes showed a more complex pattern: at 6 months, most secondary measures favored the combined approach, but at 12 months pain and function scores (HOOS) actually favored combined treatment, while quality of life and physical activity did not. The study was adequately powered and had good follow-up rates, though participants were unblinded which may have introduced bias.

These findings suggest that while weight loss amplifies improvements in disability and function, pain reduction itself may depend more on the exercise stimulus than on weight loss magnitude, raising questions about the mechanisms through which weight loss influences outcomes in this population.