A dairy-free diet does not contain any milk from an animal or any products made from milk. People may go on a dairy-free diet because they:

Read food labels and teach your child how to read them. Avoid products whose label:
Avoid all milk products, such as:
Avoid other ingredients that can contain milk, including:
Some unexpected foods might contain milk, such as:

What can I substitute for dairy? Many dairy substitutes are available, such as:
Don't substitute goat's or sheep's milk products for dairy without talking to your doctor first. These are similar to cow's milk products, so your child might need to avoid them.
How can my child get the nutrition they need on a dairy-free diet? Kids on a dairy-free diet need to replace the calcium, vitamin D, vitamin B12, and protein that they would ordinarily get from dairy foods. Choose dairy substitutes that are fortified with these vitamins, such as fortified almond, rice, oat, and soy milk substitutes. Serve plenty of calcium-rich foods like leafy green vegetables, nuts, and beans.
Talk with a dietitian or your doctor to make sure your child gets the vitamins and nutrients needed from a dairy-free diet. Give your child any vitamin supplements that your health care provider recommends.
How do we avoid dairy away from home? When eating away from home, always ask if there's any dairy in the items your child orders. If the cashier/server doesn't know, ask for an ingredient list. If no ingredient or nutrition label is available, have your child choose something else.