Should I fast on a night shift?

If you’re a shift worker, when and how often you eat plays a big role in staying healthy. This is because our internal body clock turns different body functions on or off depending on the time of day. In particular, at night our digestion is turned down. After all, we are meant to be sleeping, not eating! 

So if you’re a shift worker, should you be fasting at night? Well, sort of.

As digestion is dialled down overnight, so do the processes involved in moving the carbohydrates we eat into our cells for energy. Because of this, if we eat a meal in the middle of the night, carbohydrates from the food stay in our blood for longer than if we had the exact same meal during the day. Over time, having high blood sugar levels for longer than normal can increase our risk of type 2 diabetes and heart disease.

But when working a night shift, reaching for a meal at night can seem like a good idea to boost your energy, concentration and stay alert. Surprisingly, research shows this isn’t the case! On the flipside, eating no food over your night shift can make you feel nauseous and set the scene for overeating once work is over. The middle ground? Have a small snack but also aim for a short overnight fast, around five hours between 10pm and 6am.

It’s also a good idea to keep consistent with the number of meals and snacks you eat each day, regardless of whether you’re on a day or night shift. This is important in keeping your overall calorie intake relatively similar each day, as repeatedly eating little on one day, then a lot the next, is linked to excess weight. 

Here’s an example of what this might look like.

DAY SHIFT

When you wake 

  • Breakfast meal to fuel your shift

During your day shift 

  • Lunch meal and balanced snacks for long-lasting energy, concentration and staying alert

After your shift 

  • Dinner meal (around one to two hours before bedtime) to help you sleep and stop hunger from interrupting your rest

NIGHT SHIFT

During your night shift 

  • Before (or early in) your shift have a small dinner meal, especially if you know you won’t get a proper break

  • During your shift go for one or two small high protein snacks for staying energised, concentrated and alert

  • Aim for a short fast, around five hours

After your shift and before sleeping 

  • Small “breakfast” (around one to two hours before bedtime) to help you sleep and stop hunger from interrupting your rest

When you wake 

  • Lunch meal to fuel the rest of your day

If planning your meals around shift work is a challenge for you, book in with one of our dietitians for a more personalised plan and support.


Michelle Theodosi