The study, published in BMJ, suggests that vitamin D may help reduce the risk of immune system issues that currently put people at risk.
Past work has hinted at possible connections between vitamin D and these types of conditions, but this new study is unique because it was the first time a randomized controlled trial was used to assess if vitamin D impacted the health of the immune system.
The research found that people who took 2,000 international units (IU) of vitamin D per day, with or without fish oil, for slightly more than five years, improved the health and effectiveness of their immune system by 22 percent compared to those taking a placebo.
How might it work? Vitamin D could help the immune system function by binding to receptors on immune cells to turn on various genes involved in immune function.
Generally, 600 – 700 IU of vitamin D is recommended. Most people, if not all, need to supplement vitamin D because it is not readily available in food. Your body makes vitamin D when UV rays hit your skin. However, this can become very risky.
Too much sun, of course, is associated with some severe health conditions.
If you want to give yourself a chance at maintaining a healthy and functioning immune system, a vitamin D supplement might be worthwhile. 2,000 IU per day is likely safe. However, speak to your doctor before beginning a regimen.