Do Night Shifts Hurt Your Back? What a 2026 Study Found

Night-shift work was linked with more back and joint disorders in a 2026 study. Among 179,924 working UK Biobank adults followed for a median 13.1 years, published in BMJ Public Health, usual or permanent night-shift workers had a 15% higher risk of musculoskeletal disorders than day workers and a 30% higher risk of mechanical and pain disorders of the spine.

Key takeaways

• A prospective cohort study of 179,924 employed UK Biobank adults, published in BMJ Public Health on 27 October 2026, tracked new musculoskeletal disorders for a median of 13.1 years.
• Compared with day workers, people who usually or always worked night shifts had a 15% higher risk of any musculoskeletal disorder, a 23% higher risk of osteoarthritis and a 30% higher risk of mechanical and pain disorders of the spine.
• Over 10 years, about 81 in every 1,000 night-shift workers developed a mechanical or pain disorder of the spine, against about 62 in every 1,000 day workers.
• The study was observational: it shows a link, not proof of cause.
• One change to make: if you work nights, keep one fixed daytime sleep window after every night shift and protect it like a meeting.

What did the 2026 night-shift study find?

Night-shift workers were modestly more likely to develop back, spine and joint disorders than day workers. A team led by Wenxuan Fan, Keyu Kong and Fangchun Jin at Shanghai Jiao Tong University School of Medicine analyzed the UK Biobank records.

In absolute terms, day workers developed a new musculoskeletal disorder at a rate of about 28 per 1,000 people each year, compared with about 33 per 1,000 among usual or permanent night-shift workers. The links were stronger among people with 10 or more years of night work, and most pronounced in healthcare, manufacturing, tourism and cleaning.

Does working nights cause back and joint problems?

This study cannot show that. It was observational, and the authors note possible residual confounding, especially from obesity and physical job demands. Work schedules were self-reported, mostly once, at the start.

One detail invites caution. Shift workers who rarely or never worked nights had a 12% higher risk too, close to the 13% for some night shifts and 15% for usual or permanent nights. The authors see no clear dose-response gradient: the pattern could reflect a threshold effect of any circadian disruption, or other features of shift jobs.

The same UK Biobank questions have shown similar patterns before: a 2018 Diabetes Care analysis of 272,214 workers by Céline Vetter, Frank Scheer and colleagues linked night shift work with higher odds of type 2 diabetes.

Why might night shifts affect bones and joints?

The leading idea is circadian disruption. Night work moves sleep and meals to hours when the body clock expects rest, and light at night shifts the timing of melatonin and cortisol, hormones with strong daily rhythms that play a part in bone and cartilage upkeep. In 17,613 participants with blood protein data, the researchers found 78 candidate proteins that might link the two, which they call hypothesis-generating clues, not proof.

Everyday factors may add up too: broken daytime sleep, less daylight and less movement. In this cohort, the share of people with a healthy sleep pattern fell from 56.1% of day workers to 39.5% of usual or permanent night-shift workers. For more on how light after dark affects the body clock, read Is Light at Night Bad for You? What Owaves Said in 2013.

What can night-shift workers do?

The study authors point to circadian-friendly scheduling: forward-rotating shifts (day to evening to night), recovery periods between night shifts, limits on very long careers of night work and regular musculoskeletal checks for long-term night workers. Most of those are employer decisions.

A worker can shape the hours around the shift. A shift work disorder guideline from the American Academy of Sleep Medicine, published 24 October 2026, suggests several non-drug steps, each a conditional recommendation with low or very low certainty of evidence:

• a clockwise (forward) rotating schedule rather than a backward one
• a nap before the night shift, leaving time to shake off grogginess before driving
• bright light during the shift plus fixed daytime sleep timing, to adapt to nights
• a snack, or nothing, rather than a full meal during the night shift

These target sleepiness and sleep, not joint disease, but they protect the rhythm night work erodes. How Long Should a Nap Be? What a 2026 Study Found covers nap length.

What is the one change to make?

Keep one fixed daytime sleep window after every night shift. It is a step for steadier sleep, not a treatment for back or joint problems, and the 2026 study did not test it.

1. Pick sleep hours you can keep on every work night, such as 8:30 AM to 3:30 PM, and put them on My BodyClock.
2. Make the room dark, cool and quiet, and silence your phone.
3. After waking, get daylight and movement, such as a walk with some mobility work.
4. If you rotate, ask whether your rota can rotate forward, and plan a recovery day after a run of nights.

For a full shift plan, read Night Shift Schedule: How to Plan Sleep, Meals and Light, and for movement across the 24 hours, Sleep, Sit or Move? What a 2026 Study Found. Take the Body Clock Type quiz to see how your own timing runs.

Your day on My BodyClock

The day above on My BodyClock is a work night on a 7 PM to 7 AM shift, built around one fixed sleep window. After the commute home and a light breakfast, a dark wind-down leads into seven hours of sleep from 8:30 AM to 3:30 PM, the same hours every work night. The afternoon brings a walk outside with mobility work, a full main meal and family time before the commute in. The shift has a light snack break near 11 PM instead of a heavy meal, and a 3 AM stretch break.

Build your own version in Owaves: My BodyClock on the App Store, or join the Android waitlist.

FAQ

Is night-shift work bad for your back?

It was linked with more back problems in a large 2026 study: among 179,924 UK Biobank workers followed for a median 13.1 years, usual or permanent night-shift workers had a 30% higher risk of mechanical and pain disorders of the spine than day workers. The study shows a link, not a cause.

Does working nights cause arthritis?

This evidence cannot say. The 2026 study found a 23% higher risk of osteoarthritis among usual or permanent night-shift workers, but the authors note that body weight and physical job demands may not be fully accounted for. They call for more research on mechanisms.

Does shift work matter if you rarely work nights?

In this study, shift workers who rarely or never worked nights had a 12% higher risk of musculoskeletal disorders than day workers, close to the 15% with usual or permanent nights. The authors saw no clear dose-response pattern, so frequency alone may not tell the whole story.

How can night-shift workers sleep better during the day?

Keep the same daytime sleep hours after every shift, in a dark, cool, quiet room. A 2026 American Academy of Sleep Medicine guideline also suggests a nap before the night shift and, where shifts rotate, a forward (clockwise) rotation, with very low certainty of evidence.

Sources

1. Fan W, Kong K, Jin F, et al. Night-shift work and risk of incident musculoskeletal disorders: a prospective cohort study with proteomic mediation analysis in the UK Biobank. BMJ Public Health, published 27 October 2026;4(4):e004018. doi:10.1136/bmjph-2025-004018. https://pubmed.ncbi.nlm.nih.gov/42968936/
2. Wright KP Jr, Abbott SM, Ashbrook L, et al. Management of shift work disorder: an American Academy of Sleep Medicine clinical practice guideline. Journal of Clinical Sleep Medicine, published 24 October 2026. doi:10.1007/s44470-026-00084-w. https://pubmed.ncbi.nlm.nih.gov/42925456/
3. Vetter C, Dashti HS, Lane JM, et al. Night Shift Work, Genetic Risk, and Type 2 Diabetes in the UK Biobank. Diabetes Care, April 2018;41(4):762-769. doi:10.2337/dc17-1933. https://pubmed.ncbi.nlm.nih.gov/29440150/
4. Europe PMC. Full text of the 2026 BMJ Public Health night-shift study. https://europepmc.org/article/PMC/PMC13723902

Photos: erwinbosman / Pixabay · Pexels / Pixabay · bottlein / Pixabay · chulmin1700 / Pixabay · DanielaElenaTentis / Pixabay · mspark0 / Pixabay · ponce_photography / Pixabay