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Indicators of Lactose Intolerance in Babies

Indicators of Lactose Intolerance in Babies

If your baby has a hard time digesting lactose, the sugar in milk, they might have lactose intolerance or lactose sensitivity. This reaction to lactose can be uncomfortable for your little one and make the time after feeding difficult. Let’s look at the indicators and causes of lactose intolerance in babies and tips for managing this digestive issue.

Common indicators of lactose intolerance in babies

  • Diarrhea
  • Fussiness
  • Gas
  • Bloating
  • Stomach pain or avoiding tummy time
  • Crying

This digestive discomfort can occur anywhere from 30 minutes to two hours after consuming lactose. The degree of lactose sensitivity differs from baby to baby. This is because every baby (and every person as they get older) may have different levels of lactase in their intestines–the amount that the body produces tends to decrease with age naturally. This is why some infants have mild sensitivities that come and go. In some cases, babies are born with congenital lactose deficiency, a rare genetic disorder in which an infant’s body produces minimal or no lactase. Those who produce less lactase typically have more severe experiences.

What causes lactose intolerance?

In short, lactose intolerance is caused by an inability to digest lactose, which is one of the most important carbohydrates in breast milk and milk-based formulas.

When a baby’s digestive system is still developing, their body may not make enough of the enzyme lactase, which breaks down lactose into simple sugars that can be used for energy. Without lactase, the lactose doesn’t get absorbed, and as it passes through the digestive system, where it gets gobbled up by bacteria that live in the gut.

Many of those bacteria are there to help digest food and process healthy stool. But when they feast on lactose, they produce a lot of gas and might not help process other foods, which explains why gassiness, pain, and unusual stool are such common indicators of lactose intolerance.

Difference between lactose intolerance and lactose sensitivity

Lactose intolerance is rare in infants and causes harsh digestive issues after ingesting milk or milk products. Lactose sensitivity, however, is much more common in babies and is often temporary.

Could it be something else, like cow’s milk protein allergy?

Diarrhea, gas, and stomach pain don’t always mean lactose intolerance–they may also indicate a cow’s milk protein allergy, general digestive problems common in the first three months of life, or something else. If babies have more severe or persistent issues, ask your pediatrician about cow’s milk protein allergy and what formula alternatives could be best for your baby.

Lactose intolerance quick facts

1. Most babies have normal lactase activity at birth.

Newborns tend to have high amounts of lactase so that they can grow healthy and strong drinking milk. It’s when they get older that lactase amounts may begin to decrease. So even if your baby doesn’t have lactose sensitivity now, it’s still good to know what to look for in case they develop it later in life.

2. Certain ethnic groups are more prone to lactose intolerance.

Many studies suggest that people of African, East Asian, Hispanic, Indiginous American, Italian, and/or Jewish descent are more likely to experience lactose intolerance, although usually later in childhood or adulthood.

3. Lactose-sensitive babies can experience discomfort if they consume lactose.

Your little one could have digestive discomfort anywhere between 30 minutes and two hours after consuming lactose.

4. The degree of lactose sensitivity can differ from baby to baby.

Some babies may have mild lactose sensitivity, and it may be just a matter of managing the amount of lactose ingested. More severe or persistent issues could signal an underlying cause like cow’s milk protein allergy.

5. Switching formulas may help provide relief for your baby.

If you’re using formula and suspect your baby may be sensitive to lactose, ask your pediatrician about switching formulas. Enfamil‘s easy-to-digest NeuroPro Gentlease formula or plant-based ProSobee formula may be worth considering.

6. Many babies with lactose sensitivity will outgrow it.

Lactose sensitivity in infancy differs from lactose intolerance that can develop later in life. Even if your baby is sensitive to lactose now, know that many babies outgrow lactose sensitivity and successfully transition to cow’s milk when the time comes. In the meantime, you have lots of options to help ease your baby’s discomfort caused by lactose sensitivity.

How to manage lactose intolerance or sensitivity

If you’re breastfeeding, you can eliminate cow’s milk from your diet, along with common dairy foods like butter, cheese, and yogurt. If you are formula-feeding, try switching to a formula specially formulated for sensitive tummies that has complete nutrition.

The amount of lactose you would need to eliminate from your baby’s diet depends on how sensitive your baby is. If your baby can tolerate some level of lactose, keeping lactose that’s easy-to-digest in their diet can be beneficial.

Always check with your pediatrician before making changes to your baby’s diet or yours while breastfeeding.

When to visit a pediatrician

If your baby has diarrhea or cries and fusses soon after consuming lactose, or if they are not putting on weight, talk to your doctor. To determine if your little one is having trouble digesting milk, your pediatrician may request a stool acidity test, in which a sample is examined for lactic and other acids. Many suspected cases of lactose intolerance turn out to be other simple digestive issues that are easily managed. It’s a good idea to come prepared and bring a list of questions.

Prepping for your pediatrician appointment

To help your pediatrician determine whether your baby is sensitive to lactose, write down all your little one’s experiences:

  • How long after they finish eating do the experiences start?
  • Are there any other issues or behaviors, like fussiness?
  • Log anything you are giving your baby, including:
    • Breast milk, formula, or a combination
    • Medications
    • Vitamins or other nutritional supplements
    • Any solids
  • Note any changes in your baby lately: sleep pattern, eating habits, illness

Some questions you may want to ask about lactose intolerance in babies:

  • What does lactose intolerance or sensitivity mean?
  • What are the issues caused by lactose intolerance or sensitivity
  • Might there be another cause for my baby’s issues?
  • How can you tell if my baby has an issue with lactose?
  • What are the management options?
  • Is a lactose-free formula or minimal-lactose formula right for my baby?
  • Could a sensitive baby formula help?
  • How can my baby get enough calcium in their diet if milk products or lactose are reduced?
  • Should my baby be taking a supplement to make sure they’re getting all the necessary vitamins and minerals?
  • Do babies outgrow lactose sensitivity?

Having all your information and questions on hand will make your pediatrician appointment as productive as possible. Get even more tips for making the most out of your pediatrician visit.

And take heart—while a lactose sensitivity or intolerance may seem daunting at first, it’ll put you well on your way to having a happier, healthier baby. If you’re formula feeding, managing lactose sensitivity is often as easy as switching to a lactose-free or minimal-lactose formula.

Find more information and tips about lactose intolerance.

Ask your pediatrician about Enfamil Sensitive or ProSobee® for lactose sensitivity

If you’re feeding your baby a milk-based infant formula but are concerned your little one may have lactose sensitivity or intolerance, ask your doctor if an alternative formula, such as Enfamil Sensitive, may help. Our easy-to-digest formula is specially designed for lactose sensitivity and has a global expert-recommended amount of brain-building omega-3 DHA. For a plant-based alternative to milk-based formulas, talk to your doctor about Enfamil ProSobee formula, which has plant-sourced protein that’s easy on sensitive tummies.

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All information on Enfamil, including but not limited to information about health, medical conditions, and nutrition, is intended for your general knowledge and is not a substitute for a healthcare professional's medical identification, advice, or management for specific medical conditions. You should seek medical care and consult your doctor or pediatrician for any specific health or nutrition issues. Never disregard professional medical advice or delay seeking medical treatment, care, or help because of information you have read on Enfamil.