Three new studies from the Moores Cancer Center at the University of California, San Diego, have strongly linked vitamin D with lower risk for breast, colon and kidney cancers.
In the breast cancer study, researchers analyzed the blood-fluid (serum) levels of vitamin D in 1,760 individuals and found that those who had the lowest levels of 25-hydroxyvitamin D had the highest rates of breast cancer, and that as the levels of vitamin D increased, breast cancer rates dropped.
Doctors noted that those who take 2,000 IU of vitamin D3 per day and spend 10 to 15 minutes per day in the sun—when the weather permits—will have levels of vitamin D similar to those in the study who were 50 percent less likely to get breast cancer. The body makes vitamin D3 from the ultraviolet (UVB) rays of the sun.
In the colon cancer study, published in the February 2007 issue of the American Journal of Preventive Medicine, scientists reviewed findings from five different studies that took blood samples from healthy volunteer donors and then followed up for 25 years. Researchers divided 1,448 participants into five equal groups according to the serum levels of vitamin D and found that those who had 34 nanograms of vitamin D per milliliter of blood (ng/ml) were 50 percent less likely to have colon or rectal (colorectal) cancer than were those with the lowest levels. In the studies, vitamin D levels ranged from below 13 ng/ml to 52 ng/ml. Doctors projected that those who get a total of 2,000 IU of vitamin D3 per day from diet, supplements and sunshine will be 66 percent less likely to get colorectal cancer compared to those with the lowest vitamin D levels.
In the kidney cancer study, published in the International Journal of Cancer, researchers for the first time were able to use data from 175 countries and found that those who live closest to the equator—where sunlight is strongest—have the least kidney (renal) cancer.