by Bryan Bingham DC, DACRB
It has been shown that low level of Vitamin D in the body can increase the risk for viral upper respiratory infections (URTI). It would stand to reason that supplementing with Vitamin D would decrease the frequency and durations of viral colds but it is uncertain whether or not this is the case.
A new study published in the July 18th issue of the Journal of American Medical Associate (JAMA) looked at the effect that supplementing with Vitamin D had on URTIs. In this study children from age 1 to 5 were given either a traditional dose of Vitamin D of 400 IU/day or a high dose of 2000 IU/day.
At the end of the study, the children who received the high dose of Vitamin D did have higher levels of Vitamin D in their body, but there was not a significant decrease in URTI in the high dose children. They did find a 50% reduction in influenza but the numbers of kids with influenza were not statistically significant and therefore they were unable to determine from this particular study if a high dose Vitamin D supplementation would protect children from influenza.
There were limitations of the study that might explain the lack of support for Vitamin D supplementation for URTIs. The study started in September and many of the kids might have been protected from the lasted effects of sun exposure from the summer. Also, parents had to submit swabs from their children to verify URTIs and they’re were delays in these submissions that would skew the number of reported cases.
Research has shown that low levels of Vitamin D can leave people more susceptible to colds and flu. Although this particular study didn’t find a direct correlation between decreased colds and high dose Vitamin D supplementation other studies have made this connection.
In the study, 31 one of the kids in the low Vitamin D dose contracted influenza, but only 16 from the high dose group contracted influenza. These numbers are not large enough to have statistical significance but they shouldn’t be ignored. Considering that there were no deleterious effects from taking 2000 IU/day and there was a 50% reduction in influenza case I would say the benefits outweigh the risks.
If you were to go outside for 10 minutes in shorts and a tank top with no sunscreen your body would create 10,000 IUs from the sun’s UVB rays. With the body producing 10,000 IU from just 10 minutes in the sun it makes you wonder why the USDA recommendation is only 400 IU and 2,000 IU is considered a high dose. Also, Vitamin D is available in prescription at 50,000 IU. It is possible that even the high dose of 2000 IU/day is not enough to provide enough protection to prevent URTIs.
In summary, Children are spending less time outside during warmer months, not to mention how little kids get out in the wintertime. Vitamin D has been shown to have many beneficial health benefits with very few risks. I have been giving my kids Vitamin D Drops from Metagenics for years and intend to continue in order to make sure they are protected during the cold months where they are less likely to get Vitamin D naturally from the sun.