As of last year, new insight into the function of secretin was brought about as rodent studies showed secretin to possess potential body weight-regulating effects. In these studies, secretin was shown to increase non-shivering thermogenesis in brown adipose tissue (BAT), decrease meal size and promote meal discontinuation. The mechanisms behind these regulatory effect of secretin on energy homeostasis are unclear,
Inclusion Criteria: * Age between 18 and 75 years * Body mass index between 18.5 and 27.5 kg/m2 * Informed consent * Body weight above 50 kg Exclusion Criteria: * Anaemia (blood haemoglobin below normal range) * Known liver disease and/or alanine aminotransferase and/or aspartate transaminase \> 2 times upper normal values * Nephropathy (serum creatinine above normal range and/or albuminuria) * Clinically significant kidney function impairment or other laboratory findings leading to the diagnosis of clinically relevant disorders (thyroid dysfunction, anaemia etc) * Any physical or psychological condition that the investigators feel would interfere with trial participation