Looking for a natural boost to your immune system? Vitamin D could be the missing nutrient you’ve been trying to find. Vitamin D plays a crucial role in bone health and the maintenance of a healthy immune system. With newer research suggesting that it may also help prevent certain cancers and boost mood, it earns earns its place as one of the most vital nutrients in our bodies. It's recommended that you get between 600 and 1000 IU per day, so check out this grocery list to make sure you get the vitamin D you need.