Vitamin D is the key to our immune system. We who live so far in the North and have long winters with limited sunlight, have traditionally gotten our vitamin D from fish, and especially cod liver oil. Vitamin D is necessary for the absorption of calcium and phosphorus, which strengthen the teeth and bones. It is also important for fighting cancer.  Newer research shows that we need 5 times more vitamin D than earlier recommendations. Children and the elderly need twice as much vitamin D as adults. Among other thing sun lotions with SPF stop the transformation of sunlight to vitamin D through the skin. This is one of the reasons why you should take EQ Pure Arctic Oil every day throughout the year.