Researchers recommend taking vitamin D supplements to prevent certain cancers.

Researchers at the Moores Cancer Center at the University of California, San Diego call for prompt public health action to increase intake of vitamin D3 as an inexpensive tool for prevention of diseases that claim millions of lives each year.

Vitamin D Deficiency Linked to Increased Mortality Rates

"The high prevalence of vitamin D deficiency, combined with the discovery of increased risks of certain types of cancer in those who are deficient, suggest that vitamin D deficiency may account for several thousand premature deaths from colon, breast, ovarian and other cancers annually," according to the Moores Center research group.

"Breast cancer will strike one in eight American women in their lifetime, notes co-author Cedric F. Garland. "Early detection using mammography reduces mortality rates by approximately 20 percent. But use of vitamin D might prevent this cancer in the first place."

"African-American women who develop breast cancer are more likely to die from the disease than White women of the same age, notes Garland. African-Americans also have substantially poorer survival rates for colon, prostate and ovarian cancers as well." After making adjustments for socioeconomic status and access to healthcare, researchers conclude the difference in survival rate is linked to vitamin D deficiency.

The institution of a national public health action is strongly indicated, based on twenty-five years of worldwide studies on the benefits of vitamin D, Garland concludes. "Primary prevention of these cancers has largely been neglected, he suggests, but we now have proof that the incidence of colon, breast, prostate, and ovarian cancer can be reduced dramatically by increasing the public’s intake of vitamin D."

Supplements Recommended

Many people are deficient in vitamin D because it is difficult to reach the recommended daily dosage without taking supplements, according to Garland. He notes that foods such as milk, yogurt, cheese, and orange juice are fortified with vitamin D, but not in sufficient amounts to readily supply the daily target. "A glass of milk, for example, has only 100 IU," he points out.

Sunlight is an abundant source of vitamin D in summer months, since it plays a direct role in the body's production of the vitamin. But Garland warns, "Sun exposure has its own concerns and limitations. We recommend no more than 15 minutes of exposure daily over 40 percent of the body, other than the face, which should be protected from the sun." Some fair-skinned people shouldn’t try to get any vitamin D from the sun, he cautions. On the other hand, dark-skinned people may need more sun exposure to produce adequate amounts of vitamin D, because their heightened skin pigmentation prevents absorption of sunlight.

Residents of the northern United States are at higher risk of deficiency during the winter months.

Expanded use of vitamin D supplements should not be delayed, according to the authors. The proposed intake of 1,000 IU is half the safe upper intake established by the National Academy of Sciences. It is estimated that the cost will be about five cents per day.