Higher Daytime Light Exposure Predicts Lower Risk of Gastrointestinal Cancer Incidence and Mortality
People exposed to more natural daylight have significantly lower rates of gastrointestinal cancers, suggesting timing daily light exposure could prevent disease.
In 89,069 UK Biobank participants followed 8.8 years, higher objectively measured daytime light exposure was significantly associated with reduced gastrointestinal cancer incidence and mortality, with the strongest effect for pancreatic cancer (HR 0.47 mortality). Daytime light outperformed conventional risk factors in predictive models, suggesting circadian alignment as an underexplored cancer prevention strategy.
What the study was
- Study design
- Prospective cohort study with objective actigraphy-measured daytime light intensity (UK Biobank)
- Population
- UK Biobank participants with objective light exposure measurements
- Sample size
- 89069
- Category
- Prevention
- Maturity
- Exploratory
- Journal
- International Journal of Cancer
Why it surfaced
Large prospective UK Biobank cohort (N=89,069) with objective light measurements; novel circadian-cancer prevention signal, especially notable for pancreatic cancer (HR 0.47 mortality) which has very limited prevention options. Classified Exploratory as circadian-cancer mechanism requires replication.
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