The realities of night work
Why night shifts need different support.
Sleep, health, safety and the rest of life. Explore what research says about working nights, and why it matters for people and workplaces.

A whole day around it.
For people working nights
Your body. Your week. Your life.
The effects reach into recovery, concentration and the time you have outside work.
Sleep & thinking
Survey of 97 night workers, June 2025; 54% worked in healthcare. Devine et al., 2026
Among 86 rotating-shift nurses, sleepiness increased and attention-test performance fell after nights. Di Muzio et al., 2020
A review linked night work with short-term difficulties in attention and memory. Long-term findings were mixed. Leso et al., 2021
A case-based evidence review connected sleep loss with task performance, communication, mental health and safety. Habiburrahman et al., 2021
Study context
- The 98% figure is 95 of 97 respondents in an online convenience survey.
- Di Muzio compared the same nurses after morning, afternoon and night shifts. Habiburrahman used a nurse’s case to appraise 11 studies and reviews.
Long-term health
Health belongs in the conversation about night work.
Rotating night work was associated with higher odds of type 2 diabetes in a large UK study. Vetter et al., 2018
A review of 34 studies linked shift work with cardiovascular events. Vyas et al., 2012 Two nurse cohorts also linked longer rotating-night exposure with a small increase in coronary heart disease risk. Vetter et al., 2016
Night work was associated with metabolic syndrome across 13 observational studies. Wang et al., 2014
IARC classifies night shift work as probably carcinogenic to humans, Group 2A. IARC, 2020
Shifting sleep and meals out of line with internal body time altered glucose regulation and blood pressure in a 10-person laboratory study. Scheer et al., 2009
Study context
- Vetter 2018 examined existing diabetes and work schedules in UK Biobank; 272,214 current-schedule records. Vetter 2016 followed 189,158 female nurses across two cohorts for up to 24 years.
- Vyas pooled 34 observational studies involving over two million people. These studies describe associations.
- IARC’s Group 2A is a hazard classification. Its assessment included limited human evidence concerning breast, prostate and colorectal cancers.
- Scheer’s study was a controlled ten-day experiment on timing and physiology.
Room to recover between shifts
Nights, rotations and days off call for different plans. In a 66-unit hospital trial, reducing short rest intervals slightly improved insomnia and daytime sleepiness.
Six months; no improvement in work-related fatigue was detected.Djupedal et al., 2024A life outside the rota
Family, friends, care and plans need room too. Nurses described relying on people at home while sometimes stepping back from commitments to recover.
Qualitative survey of 449 shift-working nurses in Melbourne.Savic et al., 2019For employers and teams
The workplace case for better support.
Safety, reliable coverage, retention and performance are connected to how people work and recover.
Safety & errors
Fatigue reaches into attention, decisions and the journey home.
A systematic review linked shifts including nights and long work periods with higher accident risk. Wagstaff and Lie, 2011
Safety and productivity depend on consecutive nights, time on duty and rest breaks as well as shift timing. Folkard and Tucker, 2003
In a study of 289 night-shift nurses, 56% were sleep deprived; sleep duration was related to attention-test performance. Johnson et al., 2010
In a monitored study of 16 workers, near-crash events occurred after night work but not after a night’s sleep. Lee et al., 2016
Study context
- Wagstaff included 14 studies rated high quality. Folkard reviewed safety and productivity across different schedule features.
- Lee compared the same workers on a closed track after a night shift and after sleep. It measured driving performance in an experiment.
Attendance & retention
Schedules can shape the experience of staying and showing up.
Among 889 Norwegian nurses, shift-work disorder was associated with stronger intentions to quit or seek another job a year later. Blytt et al., 2022
Shift rotation and timing were linked with job attitudes and work–home conflict among 3,122 military police employees. Demerouti et al., 2004
Danish hospital data found 22% higher odds of calling in sick within two days of a night shift compared with a day shift. Larsen et al., 2023
44,767 cases from payroll data. An earlier review found night-work sick-leave evidence inconclusive. Merkus et al., 2012Study context
- Blytt measured turnover intention, not actual departures. Demerouti found rotation most clearly related to job attitudes and shift timing to work–home conflict.
- Larsen compared shifts within the same people. Reported odds ratio: 1.22. Merkus reviewed 24 studies and found results varied by schedule and population.
Performance & cost
Commercial consultancy estimate, 2024. CIRCADIAN, 2024
The estimate combines lost productivity, absence, turnover, healthcare, accidents and workers’ compensation.
A model for two U.S. manufacturers estimated additional healthcare costs associated with shift work. McHugh et al., 2020
NSC’s fatigue calculator helps employers explore costs from sleep deficiency, including absence, lost productivity and injuries. National Safety Council
What the estimates cover
- CIRCADIAN combines proprietary data with independent and third-party research. The amount is its estimate.
- McHugh modelled two manufacturers with 2,647 and 1,346 employees using disease-risk estimates and Medicare cost data.
- The NSC calculator uses employer inputs and published research.
Access to support
People want help that fits the hours they work.
One survey of 97 night workers, June 2025; 54% worked in healthcare. All figures below are from this sample.
Fitting the work schedule was the highest-ranked app feature. Devine et al., 2026
Survey context
- Online convenience sample. The counts were 78 of 97 for sleep/rest difficulties, 84 of 97 for proposed-app interest and 93 of 97 for equal or greater interest with employer funding.
- The survey asked about a hypothetical app. Feature rankings were collected from all 97 respondents.
For individuals
Tools for your kind of week.
Explore planning, learning and everyday guidance for nights, changing shifts and life around them.
See inside the appFor organizations
Support across every rotation.
Explore workforce programs, the employee app, learning and resources built around night teams.
Explore support for teams