Freinkel's early research covered the effect of different substances on the thyroid gland, the effect of alcohol consumption on glucose metabolism, and the homeostasis of insulin. In the 1970s and 1980s, he focused on gestational diabetes, a form of diabetes in pregnant women.[1] His contribution to changing treatment programs for pregnant women with diabetes led to a significant reduction in mortality rates for their offspring.[3] His research on diabetes in pregnancy earned him honorary degrees from two Swedish universities in 1981: Uppsala University and Umeå University.[1]
The American Diabetes Association annually presents the Norbert Freinkel Award, which recognizes "Outstanding Scientific Achievement in the Understanding and Treatment of Diabetes and Pregnancy".[5]