As novel approaches to gathering and analyzing data emerge at an unprecedented pace, one of medicine’s most vital population health tools remains a 43-year-old survey sent exclusively to nurses. The Nurses’ Health Study, started by Brigham and Women’s Hospital researchers in 1976, has evolved from a questionnaire sent to 171,000 U.S. nurses to examine long-term oral contraceptive use, to the world’s largest and longest-running investigation of women’s health.

Among the public health insights and recommendations that have emerged from the survey over the past four decades: the link between smoking and heart disease; the health risks of consuming trans fats, red meat, and fruit juice; the benefits of vitamin D in preventing and easing symptoms of multiple sclerosis (MS); and, today, an emerging understanding of biomarkers linked to early pancreatic cancer.

This wide range of discoveries is due in part to study subjects who are both equipped and eager to share rich insights. “In population studies like this, it’s a dream to find such motivated participants because the more data we have, the more health conditions we can study,” says Francine Grodstein, ScD, director of the Nurses’ Health Study and an epidemiologist at the Brigham.

Today, more than 1,000 researchers worldwide access data from the Nurses’ Health Study, including both the questionnaires and biospecimens from a large biobank considered pioneering when the study was launched. Their investigations have identified many disease risk factors as well as ways to increase survival rates, and influenced laws, public health policies, and U.S. guidelines on diet and physical activity.

“With current technologies, we can generate data we couldn’t have dreamed of before, giving us an unprecedented opportunity to understand the biological causes of disease and better prevent, diagnose, and treat medical conditions affecting so many people,” says Edwin Silverman, MD, PhD, chief of the Channing Division of Network Medicine, which employs the roughly 100 epidemiologists, biostatisticians, and other Nurses’ Health Study staff.

Read more on the landmark study in Brigham Health.