You should take a vitamin D supplement all the time. There is no way you can get enough from diet or the sun. It is the steroid for the immune system. I would r

You should take a vitamin D supplement all the time. There is no way you can get enough from diet or the sun. It is the steroid for the immune system. I would recommend the following 3 vitamins to strengthen the Immune system. D,C and Zinc. D is a fat soluble vitamin which means take it with some fat (in a meal or with a fish oil supplement).