Our main source of vitamin D is the sun, so as we move into winter where we tend to cover up more with warm clothing and spend less time outdoors it is important to make sure we are getting our vitamin D through supplement form. Vitamin D can be found in a few foods, but we don’t get nearly enough of it. So supplementing with it is the best way to prevent a deficiency. Being deficient in vitamin D can make you more susceptible to illness - we need it to help keep our immune system balanced. Studies have shown a link between vitamin D deficiency and respiratory track infections such as bronchitis and pneumonia. Something we definitely want to be avoiding right now!