Lactose intolerance is when the body can’t easily break down or digest lactose. Lactose is a sugar found in milk and milk products.
If your child is lactose intolerant, he or she may have unpleasant symptoms after eating or drinking milk products. These symptoms include bloating, diarrhea, and gas.
Lactose intolerance is different from having a food allergy to milk.
Lactose intolerance happens when the small intestine doesn’t make enough of a digestive juice, or enzyme, called lactase. Without enough lactase, the body can’t break down or digest lactose.
Lactose intolerance can happen to both children and adults. Some common causes include:
In very rare cases, some newborns can’t make any lactase from birth.
Your child is more at risk for lactose intolerance if he or she:
Symptoms often begin to appear in white children after age 5. They appear in African-American children as young as 2 years old.
Symptoms begin about 30 minutes to 2 hours after having foods or drinks containing lactose. Each child’s symptoms may vary. Symptoms may include:
How severe your child’s symptoms are will depend on how much lactose he or she has had. It will also depend on how much lactase your child’s body makes.
The symptoms of lactose intolerance may look like other health conditions. Always see your child's healthcare provider for a diagnosis.
Your child’s healthcare provider will give your child a physical exam and take a health history.
Your child may need to be tested. The most common tests used to check how lactose is absorbed in the digestive system include:
Treatment will depend on your child’s symptoms, age, and general health. It will also depend on how severe the condition is.
No treatment will help your child’s body make more lactase. But you can manage your child’s symptoms with a diet that limits lactose. Your child may not have to stop eating all foods with lactose. Your child's healthcare provider may also suggest your child take lactase enzymes. They are sold over the counter.
Here are some tips for managing lactose in your child’s diet:
Talk with your child’s provider about what products or diet changes may help your child. You may also find it helpful to see a registered dietitian.
Children and teens who are lactose intolerant may have little or no milk in their diet. But milk and dairy products are a major source of calcium. If your child is lactose intolerant, be sure that he or she gets enough calcium. Calcium is needed for growing and repairing bones throughout life. Calcium may also help prevent some diseases.
The amount of calcium your child needs will vary by age:
Recommended dietary amount of calcium (mg per day)
0 to 6 months
6 months to 1 year
1 to 3 years
4 to 8 years
9 to 18 years
Many nondairy foods are high in calcium, including:
Other nondairy foods that are good sources of calcium include:
Always talk with your child’s healthcare provider. Your child's provider may prescribe a calcium supplement if your child can’t get enough calcium from his or her diet.
Vitamin D is needed for the body to absorb calcium. It’s important that your child’s diet has enough vitamin D. Sources of vitamin D include eggs and liver.
Children under 1 year old should have a vitamin D supplement of 400 IU a day. Children over 1 year old should have 600 IU of vitamin D a day.
Lactose intolerance can cause unpleasant symptoms. But in most cases you don’t need to remove all foods with lactose from your child's diet. By watching your child's symptoms, you can find out which foods he or she can handle. You can also tell which foods your child should avoid.
When foods are removed from your child's diet, you must replace them with other foods that offer needed nutrients. Also make sure that your child has enough calcium and vitamin D.
The symptoms of lactose intolerance may look like symptoms of other disorders. Have your child checked by his or her healthcare provider if your child has:
Tips to help you get the most from a visit to your child’s healthcare provider:
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