1. Metabolism Unit, Division of Endocrinology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA.
2. Eli and Edythe L. Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA.
3. Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, USA.
4. Department of Social Medicine, University of North Carolina, Chapel Hill, Carolina, USA.
5. Health Policy Research Center at the Mongan Institute, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA.