Doctors have known for a long time that people who are sick often have very low blood levels of vitamin D. This naturally led to the assumption that taking vitamin D supplements might help fight disease.
In a recent paper, however, Trevor Marshall, Ph.D., professor at Australia's Murdoch University School of Biological Medicine and Biotechnology, argues that this assumption is wrong.
... Supplemental vitamin D has been used for decades, and yet the epidemics of chronic disease, such as heart disease and obesity, are just getting worse.
Marshall explains that our bodies contain something called a Vitamin D Nuclear Receptor (VDR), which plays a key role in our immune response to cancers, multiple sclerosis and other diseases. The VDR lowers vitamin D levels as a normal part of our body's response to disease. In other words, low levels of vitamin D in sick people are a sign that the immune system is doing its job.
Published in the current issue of the journal BioEssays, Marshall's research shows that even small doses of ingested vitamin D can interfere with the proper operation of the immune system.