University of California San Diego researchers have found a clear association between limited exposure to sunlight (ultraviolet B, which triggers production of vitamin D in the body) and breast cancer.

They used worldwide data available through GLOBOCAN, a database of cancer incidence, mortality and prevalence for 175 countries. They plotted incidence rates by latitude, and found breast cancer rates were highest at the highest latitudes in both the north and south. They controlled for known variables such as meat, vegetable, alcohol and cigarette consumption.

Three previous studies using GLOBOCAN data found similar vitamin D associations for kidney, ovarian and endometrial cancers.

See Also New studies back vitamin D for cancer prevention

University of California at San Diego News Release