Expert Commentary: Dr. Jonathan Donath April 23, 2009

Traditionally Vitamin D deficiencies have been related to disease of the bone, such as rickets and osteoporosis. Today researchers are finding correlations between Vitamin D deficiency and many chronic diseases. And the list is quite large:  high blood pressure, tuberculosis, cancer, periodontal disease, multiple sclerosis, chronic pain, peripheral artery disease. Some research shows that Vitamin D deficiency may impair cognitive function, meaning memory loss and foggy brain. So much for getting older. And it even has an impact on autoimmune diseases such as Type 1 diabetes. 

Well, what does this all mean? Correlation?  We haven't yet found direct cause and effect. But typically studies demonstrate that if a patient is diagnosed with breast cancer , there is likely to be low level of vitamin D in the body.  It doesn't tell us though whether the disease causes the vitamin D deficiency or whether the Vitamin D deficiency contributes to the disease. The old chicken and the egg question.

But does Vitamin D help prevent these diseases?  A lot of research is going on in this direction demonstrating that maintaining adequate high levels of Vitamin D may be preventive.  Intriguing results, but far from proven.  Though some physicians are now advising patients to take Vitamin D3 supplements.

Now we also have to be careful here. In the past research ballyhooed the next great vitamin as a savior. Remember back to the days of Linus Pauling and Vitamin C. All the research was suppose to show that Vitamin C would cure everything from the common cold to cancer. And while Vitamin C is important,  the final results of the impact of Vitamin C on overall health was far more mixed. And then there was Vitamin E. Similar excitement in the media about its potential with mixed results over the long term .

Still, let's remain hopeful that this time we will find that this inexpensive supplement may have dramatic impact on improving our health nationwide - a critical factor for saving our healthcare system.

And one final but important reminder. Any supplement taken in too large a dose can be harmful. Always check with your healthcare provider at to what dose is right for you.