In 2016 Kay started his PhD at Maastricht University at the department of Nutrition and Movement Sciences under supervision of prof. Vera Schrauwen-Hinderling, prof. Patrick Schrauwen, and dr. Lucas Lindeboom. During his PhD he investigated substrate metabolism in people with NAFL within a TKI/Health Holland consortium with partners from Leiden University Medical Center and Unilever R&D. Specifically, he focused on the role of hepatic saturated fat and hepatic glycogen. In this human research he applied both invasive techniques, such as hyperinsulinemic-euglycemic clamps, and non-invasive techniques, such as Magnetic Resonance Spectroscopy (MRS). By applying both methods in human studies he has provided novel insights in how liver substrate metabolism is changed in NAFL and what the implications can be in terms of metabolic health.
After finishing his PhD, Kay continued his career as a postdoctoral researcher at the Department of Nutrition and Movement Sciences. To further investigate the role of hepatic saturated fat and de novo lipogenesis in determining insulin sensitivity, he was awarded an EFSD fellowship in 2021, together with Prof. Vera Schrauwen-Hinderling. In 2022, Kay received a junior fellowship grant from the Dutch Diabetes Foundation. This grant will enable him to investigate (liver specific) gluconeogenesis late in the evening in people with prediabetes and to investigate whether lowering this process helps to improve metabolic health.