Vitamin D Improves Overall Immune Function

Dr. Ilkka Laaksi and her team evaluated a group of 164 males going into the military to see if vitamin D supplementation affected their overall health. They gave part of the group 400 international units (IU) of vitamin D a day for six months, and the other part of the group a placebo pill for the same period of time. Those who took vitamin D experienced greater overall health and less respiratory infections than those who did not.

Laaksi was quick to say that the study reveals "some evidence" that vitamin D helps prevent respiratory infections, but that such a benefit is not entirely clear.

Though 400 IU of vitamin D a day meets recommended government intake recommendations, many in the medical profession are now realizing that this level is far too low to offer much therapeutic effect. Some suspect that if a higher dose had been used in the study, the effects would have been even more significant.

This hypothesis was illustrated in a recent Japanese study that administered 1,200 IU doses of vitamin D to schoolchildren. Those who took this dose every day had a much lower chance of developing influenza than others.

It is, however, unclear which form of vitamin D the team used in the Finland study. Vitamin D2 is not as effective as vitamin D3, but researchers often use D2 in study trials, which can make vitamin D appear less effective.