You've probably noticed that people who work night shifts often gain extra weight - but why does it happen?
Scientists have discovered why working night shifts can affect a person's appetite.
This research can be helpful for the millions of people who work night shifts and struggle with weight gain.
The study focused on how 'circadian misalignment,' which is similar to jet lag, affects hormones that control hunger.
In particular, they looked at glucocorticoid hormones in the adrenal gland, which play a role in metabolism and appetite regulation.
Using animal models, the researchers found that when the daily rhythm of these hormones was out of sync with light and dark cues (like what happens during night shifts), it caused certain brain peptides responsible for controlling appetite to become disordered.
This disruption led to an increased desire to eat during the inactive phase of the day, even when the animals were not more active during that time.
The study showed that timing of food consumption is crucial.
Rats with normal rhythms ate most of their food during their active phase, while the 'jet-lagged' rats consumed a significant portion of their daily calories during their inactive phase.
This discovery highlights how important it is for people working night shifts to maintain a regular daily routine as much as possible, including mealtimes and exposure to daylight.
The study also suggests that the brain peptides identified may be potential targets for drugs designed to treat eating disorders and obesity resulting from circadian misalignment.