Higher serum levels of the main circulating form of vitamin D, 25-hydroxyvitamin D
(25(OH)D), are associated with substantially lower incidence rates of colon, breast, ovarian, renal, pancre-
atic, aggressive prostate and other cancers.
Epidemiological findings combined with newly discovered mechanisms suggest a new model
of cancer etiology that accounts for these actions of 25(OH)D and calcium. Its seven phases are disjunction,
initiation, natural selection, overgrowth, metastasis, involution, and transition (abbreviated DINOMIT).
Vitamin D metabolites prevent disjunction of cells and are beneficial in other phases.
It is projected that raising the minimum year-around serum 25(OH)D
level to 40 to 60 ng/mL (100–150 nmol/L) would prevent approximately 58,000 new cases of breast cancer
and 49,000 new cases of colorectal cancer each year, and three fourths of deaths from these diseases in the
United States and Canada, based on observational studies combined with a randomized trial. Such intakes
also are expected to reduce case-fatality rates of patients who have breast, colorectal, or prostate cancer by
half. There are no unreasonable risks from intake of 2000 IU per day of vitamin D
, or from a population
serum 25(OH)D level of 40 to 60 ng/mL. The time has arrived for nationally coordinated action to substan-
tially increase intake of vitamin D and calcium.