Tread carefully when your elderly patients are prescribed weight-loss diets. You may consider the impact for your falls reduction or other interventions. "Weight loss can increase hip fracture and lead to functional disability," cautions physician John Morley at St. Louis University School of Medicine. "When you lose weight, you lose 75 percent fat and 25 percent muscle and bone," he adds. "And when you are older and frail, loss of muscle and bone is a much bigger problem."