His research interests include mechanisms of insulin action in the ovary,[1] endocrinological aspects of AIDS,[2] and clinical outcomes in diabetes.

[6] While at Beth Israel Medical Center (2000 - 2014), Dr. Poretsky served as Chief of the Division of Endocrinology, Vice-Chairman for Research, and Interim Chairman in the Department of Medicine.

An endocrinology fellowship program was initiated in July 2016 and a new site for the Gerald J. and Dorothy R. Friedman Diabetes Institute at Lenox Hill Hospital opened on August 1, 2016.

In the 1990s he wrote a letter to the editor of New York Times concerning how Medicaid payment caps can limit physicians' availability to patients.

[23] While working as a research fellow at Harvard in the early 1980s, Poretsky became known for discovering, describing and characterizing insulin receptors in the human ovary.

[24] Before his research, the hormone insulin had been known to primarily regulate glucose and other fuel metabolism in the liver, fat, and muscle.

[24] Subsequently, Poretsky’s work became important for understanding more common disorders, such as polycystic ovary syndrome (PCOS), which affects up to 10% of reproductive age women and is associated with infertility and diabetes.

[27][28] Poretsky and his coworkers also characterized related receptors in the ovary (insulin-like growth factor receptors,[29] peroxisome-proliferator activated receptor-gamma),[30][31] embarked on early studies of the newly discovered energy metabolism hormone irisin in reproduction,[32] and conceptualized an insulin-related ovarian regulatory system.

[33] Additionally, in 1987 Poretsky was a key member of the team which described a condition called hyporeninemic hypoaldosteronism, which is characterized by deficiency of adrenal hormone aldosterone, in patients with AIDS.

[35] He also studied the metabolism of adrenal hormones cortisol[36] and dehydroepiandrosterone (DHEA)[37][38] in patients with human immunodeficiency virus (HIV).

Recent publications include an invited editorial in the Proceedings of the National Academy of Sciences on the role of advanced glycation end products (AGEs) in metabolic disease;[39][40] a study of the potential new treatment for prevention of diabetic nephropathy (carried out in collaboration with investigators from the Mount Sinai School of Medicine);[41] a review of the role of Vitamin D in human reproduction;[42] and an editorial as well as a clinical research study[43] on the problem of recurrent hospitalizations of patients with diabetes.