Lactose intolerance in toddlers, is this normal?

Babies are born with an enzyme called lactase which helps them digest the lactose naturally found in breast milk and cow's milk. However, from ages 3 to 7, some children may begin to lose lactase activity and develop an intolerance to dairy. While lactose intolerance is common as people age, it is not common in children under the age of 3. 

What causes lactose intolerance under the age of 3? 

If your child doesn't seem to digest dairy well, he or she may have a temporary intolerance to dairy. Temporary intolerances can be caused by infections, food poisoning, or injury to the intestines. In any of these cases, dairy should be avoided until your child is healed from whatever made her or him sick. It usually takes about a month for the intestines to heal after a sickness.  

Replacements for cow's milk 

If your child is sensitive to cow's milk or does not like to drink it, it is important to offer your child other foods that can replace the nutrients found in milk. Cow's milk is a great source of calcium, phosphorus, and protein, whether they are whole milk or have less fat (1% or 2%). They all support your child's healthy growth. Plant milks and some juices have calcium added (check labels!) are great sources of calcium and vitamin D; however, they do not have enough protein in comparison to cow's milk.