A viewer asks: “Professor Angus Dalgleish, the chair of oncology at St George’s, University of London, has conducted research and clinical work on the role of vitamin D in cancer, particularly focusing on its potential benefits for cancer patients. He prescribes very high doses of vitamin D to some cancer patients to raise their blood levels significantly to boost vitamin D levels to around 100 nmol/L. How beneficial, as part of a comprehensive cancer treatment approach, are such doses likely to be and how variable in outcomes for different patient demographics?” What can Creator tell us?

This is a general tonic that helps tune up immune surveillance and, as the primary bulwark in the body's defense against malignancy, that will be a complementary benefit to any other therapy for ongoing treatment of a malignant condition. It is not the be-all and end-all of cancer treatment but a useful adjunct. We cannot give you an encyclopedic tour of all possible conditions and the many variables that will influence an individual response, and to what degree it can make a difference of a practical sort, but it is a useful step to take, especially considering the dearth of useful therapies that are not destructive by design with all the many side effects of current cytotoxic chemotherapy.