by WYNNE PARRY
Jules Hirsch, an early leader in the study of human metabolism, died at age 88 in Englewood, New Jersey, after a long illness. His research, conducted at The Rockefeller University, helped establish the biological underpinnings of obesity, challenging the notion that the disease results from a lack of will power.
“Jules Hirsch was a brilliant clinical investigator whose meticulous studies led to his landmark discovery that the body responds to weight loss by reducing energy expenditure, providing a crucial new insight into why obese individuals have so much difficulty losing weight and sustaining the weight loss,” says Barry Coller, vice president for medical affairs and the current physician-in-chief of The Rockefeller University Hospital.
Dr. Hirsch joined Rockefeller’s faculty in 1954 and remained there for the rest of his career. In the late 1950s, when he became interested in studying obesity, most scientists considered fat, or adipose tissue, to be biologically inert — a passive insulator in which the body stores energy in the form of triglycerides. Over the next decades, Dr. Hirsch’s research helped to alter this view by highlighting the dynamic interactions among diet, metabolism, and obesity.
Early in his career at Rockefeller, Dr. Hirsch worked with Edward H. Ahrens, Jr., to pioneer techniques for separating and studying fats in blood and adipose tissue, as well as new methods for more easily obtaining patient research samples. These advances allowed Dr. Hirsch and colleagues to study how people’s diets affect their blood concentration of different types of fats, contributing to a growing understanding of the relationship between diet and heart disease.
Dr. Hirsch was physician-in-chief of the hospital from 1992 to 1996. During that time, in 1995, he published what was perhaps his most widely known study, which offered an explanation for why people who lose weight tend to regain it over time. The study was quickly cited as a classic in the field for its exploration of the regulation of human body weight.
During the more than 10-year-long clinical study, Dr. Hirsch and his colleagues gave volunteers, who were obese or who never had been, precisely defined formula diets to make them gain or lose ten percent of their body mass. The researchers carefully monitored their food intake, energy expenditure, and weight changes.
In 1987, when Olga Ford, a nursing assistant at the hospital, began working with Dr. Hirsch on this study, his concern for study volunteers impressed her. “When he interacted with the patients, he was genuinely concerned with their lives as a whole,” Ford says. “In addition to the many physical complications that can accompany obesity, the condition affects someone emotionally, and he made a point of talking with the patients about how their weight affected that aspect of their lives.”
Born in New York City in 1927, Dr. Hirsch received his undergraduate education at Rutgers University and earned his M.D. at Southwestern Medical School, University of Texas–Dallas in 1948. After an internship at Duke University Hospital, a residency at Upstate Medical Center in Syracuse, New York, and two years as an officer in the Public Health Service, Dr. Hirsch joined Rockefeller University (then The Rockefeller Institute) as an assistant physician. By 1967, he was a professor and senior physician, and he was named Sherman M. Fairchild Professor in 1988.
Among many honors and awards, Dr. Hirsch was elected to the Institute of Medicine, and he received the Stunkard Lifetime Achievement Award from The Obesity Society in 2006.
Dr. Hirsch is survived by his two sons, David and Joshua, and his nieces and nephews, Shirley Kaplan, Linda Sinins, Joseph Hirsch, Susan Berger, Norman Silber, and Michael Silber. He was predeceased by his wife, Helen Davidoff Hirsch, as well as by his siblings, Mildred, Chester, and Ann. He died on July 23.