Sources of Vitamin D:

Sunshine eggs, fish-liver oils (such as cod liver oil, saltwater fish, and fortified milk.

Vitamin D aids calcium metabolism and increases bone density. This is very important for the bodybuilder desiring to make great gains in strength. Ideally, 400 IU is recommended for vitamin D everyday, but levels higher than 1,000 IU a day may lead to hypercalcemia.