For shift workers, eating at irregular times is par for the course, but a new research study has concluded that a simple snack rather than a meal could be helpful in reducing sleepiness while maximising alertness and productivity on the night shift.

Over a seven-day simulated shift work protocol, the study, carried out by scientists at the University of South Australia, assessed the impact of three eating patterns:

  • a meal comprising 30% of energy intake over a 24-hour period, eg a sandwich, muesli bar and apple

  • a snack comprising 10% of energy intake, eg just the muesli bar and an apple

  • no food intake at all.

In each case, the food was eaten (or skipped in the case of the third option) just after midnight at 12:30am.

The 44 participants were randomly split into the three test conditions and were asked to report on their levels of hunger, gut reaction and sleepiness.

The results showed that while all participants reported increased sleepiness and fatigue and decreased vigour across the night shift, consuming a snack reduced the impact of these feelings more so than a meal or no food at all.

The snack group also reported having no uncomfortable feelings of fullness as noted by the meal group.

Lead researcher Charlotte Gupta says the finding has the potential to help thousands of shift workers who work during the night.

She said, "In today's 24/7 economy, working the night shift is increasingly common, with many industries — health care, aviation, transport and mining — requiring employees to work around the clock.

"As a night-shift worker, finding ways to manage your alertness when your body is naturally primed for sleep can be really challenging…

"The findings will inform the most strategic eating patterns on-shift and can hopefully contribute to more alert and better performing workers."

Last reviewed 12 August 2019