Cancer Health Center

Low Vitamin D Levels Linked to Advanced Cancers

Vitamin D Supplementation continued...

The average vitamin D levels of the supplemented patients rose to about 35 ng/mL -- in the normal range.

Now the patients have to be followed for months and years to see if vitamin D supplements appeared to reduce the chance of cancer spread and extend lives, Churilla says.

Phillip Devlin, MD, a radiation oncologist at Harvard Medical School, tells WebMD that such a study does not show cause and effect, only an association between low vitamin D levels and stage III cancer.

Churilla agrees. It could be that people with stage III cancer are more likely to have low vitamin D levels because they are sicker and don't eat as well or get out in the sun as much as people with less advanced cancer, he says.

Devlin says the study generates interesting ideas that need to be tested in larger, longer studies.

"We do not recommend vitamin D supplementation for cancer patients at this point," he says.

These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.