Symptoms of Lactose Intolerance in a Toddler

Any toddler might have gastrointestinal symptoms occasionally. When your child has them on a regular basis, however, it could be related to diet. Lactose intolerance is a deficiency in the enzyme toddlers need to break down the milk sugar called lactose. Symptoms of lactose intolerance are far more likely to occur in older children and adults, but toddlers can experience temporary or ongoing lactose intolerance symptoms such as gas and diarrhea.

Milk is a good source of calcium, which toddlers need for strong bones.
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Increased Gas

Excessive abdominal gas is a common symptom of lactose intolerance in a toddler. When a carbohydrate such as milk sugar is not digested in the small intestine, bacteria in the large intestine break it down, producing gas. Increased gas could cause your little one to have a noisy stomach with a lot of gurgling. If your child's abdomen looks distended or she frequently passes large amounts of gas after drinking milk or eating milk products, it could be related to lactose intolerance.


Diarrhea is hallmark symptom of lactose intolerance. Lactose that is not properly digested and absorbed remains in the colon, where it attracts fluid. The excess fluid makes the stool watery, leading to sudden, intense bouts of diarrhea with lots of gas. This can cause even a potty-trained toddler to have accidents. The stool passed tends to be more acidic than a normal bowel movement, which can cause skin irritation. Your toddler may complain of a sore bottom or start scratching her bottom because of this skin irritation.

Abdominal Discomfort

Abdominal cramps or pain can also indicate lactose intolerance in a toddler, especially if they occur relatively soon after eating. Some toddlers may experience nausea, although vomiting is uncommon. Symptoms can occur within as little as 30 minutes of eating or drinking high-lactose foods. A toddler with lactose intolerance can often tolerate a small amount of dairy products -- especially in a form such as cheese or yogurt -- eaten with a meal containing other foods and will have no symptoms. If your toddler develops gas and diarrhea shortly after she has a large glass of milk on an empty stomach, however, it could be because of lactose intolerance.


Some degree of lactose intolerance is common as children reach their teens and adulthood. In a September 2006 policy statement, the American Academy of Pediatrics notes that, by adulthood, approximately 70 percent of the world's people have some level of lactase deficiency. The condition, however, is much less common in toddlers. The AAP statement points out that lactose intolerance is uncommon in white children younger than 5, but approximately 20 percent of Hispanic, Asian and black children exhibit symptoms before age 5. The AAP does not recommend eliminating milk products for toddlers or children with lactose intolerance, but it does suggest controlling the amount and type of dairy products in their diet. If you suspect your child may have lactose intolerance, talk with your doctor about the next steps for diagnosis and treatment.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.
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