Lactose intolerance is poorly understood in the Australian community. There are lots of myths and misunderstandings about it, especially when it comes to babies.
Contrary to what you may hear:
Removing dairy from your diet makes no difference. There will not be less lactose in your breastmilk if you stop eating dairy products.
There is no relationship between lactose intolerance in adult family members (including mum) and in babies. They are different types of lactose intolerance.
A baby with symptoms of lactose intolerance should not be taken off the breast and fed on soy-based or special lactose-free infant formula.
Lactose intolerance is very different to intolerance or allergy to cows' milk protein.
Some facts about lactose
Lactose is the sugar in all mammalian milks. It is produced in the breast. The amount of lactose in breastmilk isn’t related to the amount of lactose you consume and it hardly changes. The milk baby gets when they first start to feed contains about the same amount of lactose as the milk at the end of a breastfeed. However, the milk at the end does contain more fat.
Lactase is the enzyme that is needed to digest lactose. Lactose intolerance occurs when a person does not produce this enzyme, or does not produce enough of it, and is therefore unable to digest lactose. If it isn’t digested and broken down, it can't be absorbed. If this happens, the lactose continues on in the digestive tract until it gets to the large bowel. It is here that bacteria break it down to make acids and gases.
Lactose intolerance in babies
Primary (or congenital) lactose intolerance:
This is an extremely rare genetic condition. The baby is born without any lactase enzymes. They fail to thrive from birth (ie not even start to gain weight) and show obvious symptoms of malabsorption and dehydration. This is a medical emergency and the baby would need a special diet from soon after birth.
Secondary lactose intolerance:
Because the enzyme lactase is produced in the very tips of the microscopic folds of the intestine, anything that damages the gut lining can cause secondary lactose intolerance. Even subtle damage to the gut may wipe off these tips and reduce the enzyme production, for example:
food intolerance or allergy. In breastfed babies, this can come from food proteins, such as in cows' milk, wheat, soy or egg, or possibly other food chemicals that enter breastmilk from the mother's diet, as well as from food the baby has eaten.
parasitic infection such as giardiasis or cryptosporidiosis.
coeliac disease (intolerance to the gluten in wheat and some other grain products).
following bowel surgery.
The symptoms of lactose intolerance are liquid, sometimes green, frothy stools and an irritable baby who may pass wind often.
My baby has these symptoms. Do they have lactose intolerance?
It can be difficult to know because these symptoms may also occur in a baby with other conditions.
Lactose overload can look the same as lactose intolerance and is frequently mistaken for it. You may like to check the information on lactose overload to see if it matches what you see in your baby. Many mums find relief from their and their baby’s symptoms by addressing lactose overload first.
Food allergies and food intolerances can cause a baby to be unsettled. The foods to which a baby is allergic or intolerant can pass through the mother's breastmilk. It can sometimes help for mum to remove the particular food, for example cows’ milk protein, from her diet. However, this needs guidance from a dietitian to help identify the problem foods and to make sure your diet is nutritionally adequate for both you and your baby.
Cows' milk protein allergy (or intolerance) is often confused with lactose intolerance and many people think they are the same thing. They aren't. People probably get confused because cows' milk protein and lactose are both in the same food, that is dairy products. Since allergy or intolerance to a food protein can cause secondary lactose intolerance, the baby may have both. This adds to the confusion.
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