Light at night acutely impairs glucose tolerance in a time-, intensity- and wavelength-dependent manner in rats.

Aims/hypothesis: Exposure to light at night (LAN) has increased dramatically in recent decades. Animal studies have shown that chronic dim LAN induced obesity and glucose intolerance. Furthermore, several studies in humans have demonstrated that chronic exposure to artificial LAN may have adverse health effects with an increased risk of metabolic disorders, including type 2 diabetes.