Modern living is associated with an epidemic of type 2 diabetes mellitus (T2DM). Sleep
disturbances are strong independent risk factors for incident diabetes. Melatonin has been
implicated in regulation of circadian rhythm and sleep, but it is also ascribed
anti-oxidative properties and effects on glucose homeostasis. A potential association between
melatonin and T2DM has only been addressed in few human physiological studies, but the topic
has received renewed interest since genetic-epidemiological studies have pointed to a role
for melatonin in the development of the disease. In the current study, the investigators wish
to examine whether treatment with synthetic melatonin induces physiological changes that
affect the risk of developing type 2 diabetes. Two studies of the physiological effects of
melatonin are included in the present protocol. In study A, the investigators will examine
the acute effects of Melatonin on insulin secretion and insulin sensitivity using a Botnia
clamp and in study B the investigators will examine the potential effects of Melatonin on the
incretin response.