Answers are grounded in this paper and cite their sources.
A total of 10935 women with visual impairment were identified from the Finnish Register of Visual Impairment and followed up for cancer through the Finnish Cancer Registry for years 1983-1996. Breast cancer risk decreased by degree of visual impairment (P for trend 0.04) which suggests a dose-response relationship between visible light and breast cancer risk.
No takes yet. Share an insight, caveat, or question.
Verkasalo et al. (1999) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: