Rung Five
Myths and everyday exposures
May raise risk

Night shift work

regular overnight shifts. Work & lifestyle.

Verdict
May raise riskSome studies point to higher risk, but it isn't confirmed.
How sure
Rung 2 · LimitedFew, small or conflicting human studies, or only indirect measures such as blood markers.

The rung shows how sure the science is, not how big the effect is. How to read these ratings

Cancers affected

Breast, prostate, colorectal

What the evidence shows

The WHO's cancer agency classes night shift work as probably carcinogenic, but the human evidence for these cancers is limited; the stronger evidence comes from animal studies.

What to do

If you can't avoid night shifts, keep your other risks low and stay current with screening.

Sources

To take it to your doctor, print this page.

Step by step

For the whole picture, from prevention and screening to treatment and life after, see the breast cancer, colorectal cancer and prostate cancer pages.

Related

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