Vitamin D and cancer

Researchers in Japan believe higher levels of Vitamin D are linked to a lower risk of cancer, particularly liver cancer.  A team from the Center for Public Health Sciences at the National Cancer Center in Tokyo analyzed blood samples from more than 30,000 middle-aged participants across Japan.  The individuals were followed for an average of 15 years.  The study took into account factors including age, sex, family cancer history, smoking and seasonal differences.  

The study published in the BMJ found that higher levels of circulating Vitamin D were linked to a lower risk of cancer overall.  Compared with the quartile of individuals with the lowest levels of circulating Vitamin D, the quartile with the highest levels were found to have a 22% lower risk of cancer.  The study found a 50% lower risk of liver cancer, once diet was considered, for the individuals with the highest Vitamin D levels compared with the lowest. 

NOTE:  The study authors note this study has limitations including the possibility that the participants may be more health conscious than the general public.