Breast cancer linked to lack of sun exposure
The study, conducted by the Westmead Breast Cancer Institute, Sydney, found the risk was nearly double for those who lived at latitudes south of 30 degrees, a line stretching from Coffs Harbour in NSW to Geraldton in WA.
Using data from state cancer registries and adjusting for age, socioeconomic status and remoteness, it found the incidence rate was about 80 cases per 100,000 for those north of 30 degrees and 160 per 100,000 for those south of 30 degrees.
Co-author Professor John Boyages, director of breast oncology at the Macquarie University Cancer Institute, said it was thought the link between latitude and breast cancer was due to the reduced potential for vitamin D synthesis from sunlight.
The study, presented at the Sydney International Breast Cancer Congress, also looked at melanoma rates and found the risk was 35% lower for those living south of 30 degrees, supporting the hypothesis.
“Four of Australia’s major mainland