She is also the hospital's director of bone density testing. Nieves has co-authored more than 70 journal articles, reviews, and book chapters on nutrition, epidemiology, and osteoporosis. She is a graduate of Columbia University where she received her PhD in epidemiology, following a master's degree in nutrition from Cornell University. She has an interest in the nutritional causes of disease including osteoporosis, Alzheimer's disease, and physical function in the elderly. She is also an investigator on various studies concerning PTH treatment of osteoporosis, the role of vitamin D on skeletal health, and determinants of peak bone mass. She serves on the Editorial Board of Osteoporosis International and is the Principal Investigator for the New York State Osteoporosis Prevention and Education Program.