Shift work can misalign our internal circadian rhythms —or shift our metabolic rhythms away from our sleeping rhythms.When our external world doesn’t match our internal body cycles, our metabolism gets disrupted first.
Night work or shift work presents with common characteristics that interfere with our circadian physiological cycles: exposure to continuous light during the night, frequent snacking, fatigue and reduced physical activity.
Sleep disruption ultimately contributes to weight gain due to a shift in our appetite hormones. Naturally, when we sleep, ghrelin (hunger hormone) is lowered, and leptin (satiety hormone) rises over night.
Restricted sleep, however, causes an increase in ghrelin levels and reduction in leptin levels. Together, this leads to a sense of increased hunger and decreased fullness. Over time, excess weight can accumulate.
The situation can be complicated further when we have difficulties falling asleep after the night shift is over. This leads to less rest, and an accumulation of all the characteristics that interfere with our circadian physiological cycles all over again: exposure to continuous light during the night, frequent snacking, fatigue and reduced physical activity.
What can we do to prevent weight gain with shift work?
- Distract Breaks instead of Snack Breaks.
Elevated levels of ghrelin overnight not only increase hunger but is also increases cravings. Often, we are not eating out of physical hunger but out of boredom or for a “boost” of energy. Instead of taking a break to snack, distract yourself with something else—check your email, read the news on your phone, etc.
- Avoid Processed Food while on Shift.
Ultra-processed food and processed foods can hijack our appetites so that we continue to eat more without feeling full. This just adds fuel to the fire overnight when our appetite hormones are already off-balance. Instead, opt for high-fiber foods that will help increase satiety.
- Block out the blue light Overnight.
This is a light coming from the Sun during the day as well as artificial light from our phones, TV, and Hospital lighting. Our sleep hormone, Melatonin loves darkness to work properly. As we near the end of our shift make sure we start blocking out blue light at least one hour before our shift ends if possible (e.g. automatically set our phone to “night mode” at this time).
- Avoid caffeine later in your shift.
As we near the end of a night shift, the goal should be sleep preparation. Avoid caffeine or other stimulants that can prolong the night shift any longer.