An epidemiologic basis for estimating optimal vitamin D intake for colon cancer prevention and a public health recommendation for greater vitamin D intake

Abstract

Dose response curves derived from population-based studies can provide an epidemiological basis for estimating optimal vitamin D 3 intake for prevention of colon cancer. There have been 20 recent population-based epidemiological studies analyzing vitamin D status and risk of colon cancer. Five were studies of vitamin D metabolites in serum, and 16 analyzed oral intake of vitamin D 3 . Four of the five serum studies reported statistically significantly lower risk of colon cancer associated with higher serum 25(OH)D levels. Twelve of 16 studies of oral vitamin D 3 intake found significantly lower risk of colon cancer associated with higher vitamin D 3 intake. Dose-response gradients from these studies were plotted as trend lines. Overall, individuals with >1000 IU/day oral vitamin D 3 (p < 0.0001) or >33 ng/ml (82 nmol/L) serum 25-hydroxyvitamin D 3 (p < 0.01) had 50% lower incidence of colorectal cancer compared to reference values. Dose response curves derived from these studies indicate that a daily oral intake of 1000 IU of vitamin D 3 could be associated with as much as a 50% reduction in colon cancer incidence. A variety of epidemiologic studies have found that inadequate photosynthesis or oral intake of vitamin D 3 is associated with high incidence or mortality rates of colorectal cancer. Vitamin D 3 intake of 1000 IU daily is associated with a 50% reduction in colon cancer incidence based on dose-response curves derived from population-based epidemiologic studies. This is 2.5 to 4 times higher than the current RDA for vitamin D 3 . Vitamin D deficiency is prevalent in the United States and is readily treatable. Fortification of foods with vitamin D 3 could dramatically reduce colon cancer incidence and would be an effective public health intervention.