The impact of meal timing on performance, sleepiness, gastric upset, and hunger during simulated night shift

Crystal Leigh Grant, Jillian Dorrian, Alison Maree Coates, Maja Pajcin, David John Kennaway, Gary Allen Wittert, Leonie Kaye Heilbronn, Chris Della Vedova, Charlotte Cecilia Gupta, Siobhan Banks

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20 Citations (Scopus)


This study examined the impact of eating during simulated night shift on performance and subjective complaints. Subjects were randomized to eating at night (n=5; 23.2 ± 5.5 y) or not eating at night (n=5; 26.2 ± 6.4 y). All participants were given one sleep opportunity of 8 h (22:00 h-06:00 h) before transitioning to the night shift protocol. During the four days of simulated night shift participants were awake from 16:00 h-10:00 h with a daytime sleep of 6 h (10:00 h-16:00 h). In the simulated night shift protocol, meals were provided at ≈0700 h, 1900 h and 0130 h (eating at night); or ≈0700 h, 0930 h, 1410 h and 1900 h (not eating at night). Subjects completed sleepiness, hunger and gastric complaint scales, a Digit Symbol Substitution Task and a 10-min Psychomotor Vigilance Task. Increased sleepiness and performance impairment was evident in both conditions at 0400 h (p<0.05). Performance impairment at 0400 h was exacerbated when eating at night. Not eating at night was associated with elevated hunger and a small but significant elevation in stomach upset across the night (p<0.026). Eating at night was associated with elevated bloating on night one, which decreased across the protocol. Restricting food intake may limit performance impairments at night. Dietary recommendations to improve night-shift performance must also consider worker comfort.

Original languageEnglish
Pages (from-to)423-436
Number of pages14
JournalIndustrial Health
Issue number5
Publication statusPublished or Issued - 2017


  • Circadian misalignment
  • Hunger
  • Performance
  • Psychomotor vigilance
  • Shift-work
  • Sleep loss
  • Sleepiness
  • Timed eating

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health
  • Health, Toxicology and Mutagenesis

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