When Robert S. Sherwin, M.D., began a fellowship in 1972 in the medical school’s Department of Internal Medicine, his plan was to deepen his knowledge of metabolism and return to New York City’s Mount Sinai Hospital, where he’d completed his residency, to establish a diabetes research program. 42 years later and still at Yale, he hasn’t looked back.

Now the C.N.H. Long Professor of Medicine and chief of the Section of Endocrinology, Sherwin has been at the forefront of research that has fundamentally improved medicine’s ability to address the body’s lack of insulin production in Type 1 diabetes, an autoimmune disease that results in unregulated levels of blood glucose and, if untreated, can cause organ damage and death.

A Bronx-born New Yorker with a passion for art, Sherwin minored in art history while at Union College. After earning his M.D. at Albert Enstein College of Medicine, he planned to research kidney disease at the National Institutes of Health (NIH), but was instead accidentally offered, and accepted, a research position in a diabetes lab there. At the NIH and afterward, he came to see that treatments for Type 1 diabetes—which affects nearly 3 million Americans today—could be vastly improved.

In 1974 Sherwin joined Yale’s Department of Internal Medicine. Working with Professor of Pediatrics William V. Tamborlane, M.D., he played a critical role in the development of insulin pump therapy—in which a small pump slowly delivers insulin, stabilizing blood glucose levels. “As late as 1980 our treatments kept people with Type 1 diabetes alive, but we had no real way to monitor what we were doing or much to offer therapeutically,” says Sherwin, also director of the Yale Center for Clinical Investigation (YCCI). However, the advent of continuous infusion, along with ancillary advances like the finger prick blood test and the ability to measure glucose over an extended period, dramatically enhanced treatment.

In later research, Sherwin defined how the brain senses glucose and activates defenses against low blood sugar, or hypoglycemia—the major complication of insulin therapy. “There are adaptations in the brain that make glucose-sensing cells more efficient so people are less aware of their hypoglycemia,” he explains.

Sherwin’s research today relies on cutting-edge imaging techniques, including functional magnetic resonance imaging (fMRI) and positron-emission tomography (PET), and aims to clarify the neurological bases of hypoglycemia and obesity. Working with a diverse group of researchers—from psychiatrists to pediatricians—his research into areas of the brain that control emotion, motivation, and reward has revealed dramatic differences between the brain responses of lean and obese children. Interdisciplinary collaboration of this kind is central to the research being supported by YCCI’s five-year $45.4 million Clinical Translational Science Award—the university’s largest NIH grant—and is, he believes, key to the future of medicine.

Today, Sherwin continues to see patients despite a busy research schedule and broad administrative duties. The creativity in research and the prospect of improving the lives of many continue to excite him, he says, while acknowledging that working with patients helps keep him grounded.

“The creative struggle in research is similar to what happens when you’re trying to achieve a vision in art,” Sherwin says. “The excitement comes when things reveal themselves.”