Investigators have designed a study that simulated night work and then tested the effects of daytime and nighttime eating versus daytime eating only. The team found that, among participants in the daytime and nighttime eating group, depression-like mood levels increased by 26 per cent and anxiety-like mood levels by 16 per cent. Participants in the daytime-only eating group did not experience this increase, suggesting that meal timing may influence mood vulnerability.

"Our findings provide evidence for the timing of food intake as a novel strategy to potentially minimize mood vulnerability in individuals experiencing circadian misalignment, such as people engaged in shift work, experiencing jet lag, or suffering from circadian rhythm disorders," said co-corresponding author Frank A. J. L. Scheer, PhD, Director of the Medical Chronobiology Program in the Brigham's Division of Sleep and Circadian Disorders. "Future studies in shift workers and clinical populations are required to firmly establish if changes in meal timing can prevent their increased mood vulnerability. Until then, our study brings a new 'player' to the table: the timing of food intake matters for our mood."