Most children are ready to transition from Nutramigen (baby formula) to cow's milk at 12 months old. UCSF Children's Hospital recommends that children are given whole milk at this time because children under 2 years old need extra fat that they can't get from skim or low-fat milk. While the transition from Nutramigen to regular cow's milk may take a few weeks, it can be a smooth and painless transition for both you and your child.
Mix a bottle or cup for your child with 3/4 formula and 1/4 milk. Your child will still be able to taste the formula that he is used to, but he will also be able to taste a small amount of the cow's milk. Over the course of a few weeks, increase the amount of milk and decrease the amount of formula that you mix until your child is drinking only the milk. SafeKids suggests this as one of the easiest methods for transitioning a child to cow's milk from formula.
Mix your child's rice, oatmeal, or barley cereal with milk. This will create a new taste for your child. Because he is already comfortable with the taste of cereal, the slight alteration with the milk flavor will not come as a huge shock.
Give your child a small sip of milk when he gets thirsty instead of immediately offering Nutramigen. This can be done with a sippy cup or even using a spoon. BabyCenter suggests giving your child small spoonfuls of milk as a special treat to help him warm up to the idea of this new drink.