Vitamin D for Cancer Prevention and Survival

Higher levels of the principal circulating form of vitamin D, 25-hydroxyvitamin D (25(OH)D), are associated with substantially lower incidence and death rates from colon, breast, and ovarian cancer, with a linear dose–response gradient. The accumulated evidence from observational studies and a randomized trial reveal that population serum levels of 25(OH)D in the range of 40 to 50 ng/ml will markedly reduce incidence and mortality rates of several cancers including those of the breast, colon, and ovary. There is an immediate clinical need for cancer care providers worldwide to assure that a serum 25(OH)D level >40 ng/ml is achieved as soon as feasible after diagnosis of patients with breast and colon cancer, unless specifically contraindicated by pre-existing hypercalcemia. This serum target could be revisited after further rigorous studies are performed, but the evidence that has accumulated during the past 29 years is sufficiently strong now to adopt the above dosages and serum targets for professional and public health action. Such prompt action is likely to cut mortality from these cancers by half within approximately 5 years. Research on a wider range of cancer types with higher serum 25(OH)D levels (≥50 ng/ml or 125 nmol/l) is needed. In the meantime, vitamin D₃ intake by everyone in the continental US and Canada aged 1 year and older should not be less than 2000 IU/day of vitamin D₃, and 1000 IU/day for infants.