Vitamins play a big role in our bodies, among other things, they affect our metabolism, oxygen transfer and antioxidants. They help the body use carbohydrates, proteins and fats. Milk is a very good source of water soluble thiamin (vitamin B1), riboflavin (vitamin B2), and cobalamin (vitamin B12) while niacin (vitamin B3), pantothenic acid (vitamin B5), pyridoxine (vitamin B6), vitamin C and folic acid are present in smaller quantities, therefore milk is not considered to be the main source of these vitamins in a diet. Milk contains significant quantities of vitamins A, D and small quantities of vitamin E and K which are soluble in fats.