- Group 2 (diabetic): Subjects must have Type 2 diabetes mellitus as diagnosed by a physician or in medication history. The condition must be currently diagnosed and treated by medications and/or insulin. An HbA1C test performed either within past 3 months must be available or one will be done at the first visit by study personnel. Subjects must have no history of smoking within the last two years nor have any diagnosis of metabolic bone disease.