Overweight/Obesity: Metabolic Benefits to Reduce Stone Risk

Obesity, defined by the World Health Organization (WHO) as a BMI >30 kg/m2, is considered an epidemic in the United States and is estimated to afflict >20% of the population with nearly 11.5 million people affected nationwide (Demaria and Jamal, Gastroenterol Clin N Am 34(1):127–142, 2005). The population of overweight individuals (BMI between 25 and 30 kg/m2) is likewise increasing with as many as 40 million people affected. In fact, recent analysis would suggest that approximately two-thirds of the US population is overweight or obese (Yang and Colditz, JAMA Intern Med 175:1412–1413, 2015). Worldwide there has been an exponential increase in obesity with some countries reporting a near tripling of the rate of the obese population. The association between obesity and urolithiasis is well studied, and obesity has been demonstrated to be an independent risk factor for stone disease. This chapter will aim to describe the association between overweight/obesity and biochemical characteristics associated with stone disease in this particular group of individuals. We will also discuss nutritional therapies that decrease the risk of stone recurrence, improve 24-h urinary parameters, and are utilized to decrease weight and improve other comorbidities associated with the obese/overweight patient.