Dr James Sabetta and colleagues from Yale University School of Medicine, have published yet another article showing the benefit of vitamin D in protecting against colds and other respiratory infections.
This article which just came out followed almost 200 adults and did monthly vitamin D blood levels on all of the patients from September to early January. The patients were followed for the entire study time for developing upper respiratory infections (common cold or flu).
The findings are completely consistent with what I talk about in my book and here on my blog as well as other articles on Vitamin D and viral infections.
Those patients with a Vitamin D ( 25-Hydroxy-Vitamin D) level of 38 ng/ml or more had half the risk of a viral respiratory infection over the study. The level of statistical significance was extremely significant (p<0.0001). In addition they found that those with levels over 38ng/ml the duration of influenza was on average 2 days vs 9 days for those with low levels of vitamin D. This obviously would also affect the number of missed work days.
This study also found that higher weight individuals had lower vitamin D levels. This is consistant with other studies showing the same thing.
Another finding in the study was that over 80% of the patients in the study did have levels less then 38 ng/ml. This further emphasizes the magnitude of Vitamin D insufficiency in the United States.
The authors comment " The data in this study suggests that supplementing with vitamin D to raise the concentrations in the general population to above 38 ng/ml could result in a significant health benefit by reducing the burden of illness from viral infections, at a minimum from viral infections of the respiratory tract in healthy adults living in temperate climates".
My comment is that the authors should have gone longer with their study. They stopped in January! We know that colds and flus often still occur in February and March and that those patients NOT taking supplementary Vitamin D on their own would have had progressively lower levels in those months without sun. Had they extended their study to another 2 months, their data might have been even stronger showing the benefit of Vitamin D.
Note also that the level of 38 ng/ml in this study is very close to the lowest level (40 ng/ml) of vitamin D that I recommend ( in my book).
When was the last time you checked your vitamin D level? Your children's? You can ask your doctor or pediatrician to do a level when you go in for your next checkup. Or you can do a self test at home with an at home kit.
Let me know what you do to keep your levels up now that summer is here?
Do you get some some without sunblock? or just take a D pill every day?