Study subjects are being sought to help identify the risk factors involved in kidney stone formation. To qualify you must meet the following criteria: ages 19–65 with a BMI between 35-40. What you will be required to do: Provide 1 blood sample; provide up to four 24-hour urine collections; and consume meals provided by the UAB dietary kitchen for 3 days. Compensation is provided. If you are interested please contact Billy Tingle,