1. Disrupted
Circadian Rhythm
People tend to gain weight working shifts because of their metabolic response to the rotational nature of shift work. The metabolism follows a circadian rhythm and there is a specific pattern of rising and falling of the metabolic rate within the 24 period. Your metabolism is higher during the day and then starts to fall and is at its lowest point in the middle of the night.
During a shift rotation, people are often expected to be awake and working during the night and then sleep during the day, but then two weeks later, they may have to switch to the opposite situation. Our bodies have not been genetically programmed to operate in this way. We are meant to work and play in the day and sleep at night, as guided by our circadian clocks.
The rise and fall of the levels of the hormones: cortisol, insulin and melatonin, is circadian. If you disrupt your day/night cycle, as you will when working a rotating shift, you are disrupting the levels of these critical hormones AND you are messing with your metabolism. Elevated levels of cortisol lead to more insulin secretion which drives your body into fat storing mode. Depressed melatonin can lead to low levels of serotonin in the brain which can make people susceptible to over-eating sugar and and fatty foods to seek relief for this deficiency.
To learn more about how unhealthy levels of these hormones can make you gain weight, click on the link below: