Lactose intolerance in a new baby and relevance of mother's diet: Ask a health question

Our Health Information Line receives calls and emails from women on a broad range of health issues. This regular column features answers to some of them.

Question:  My baby is six weeks old and is very unsettled. He is being breastfed and is feeding well and putting on weight. His wees and poos seem fine (no diarrhoea). A good friend suggested his unsettledness might be due to lactose intolerance and advised me that I should eat a lactose-free diet. Is there any point to this?

Answer:  Lactose is the sugar component in milk. Humans produce an enzyme lactase in order to digest lactose. Lactose intolerance occurs when a person does not produce the lactase enzyme or does not produce enough of it. Therefore, the lactose is not digested adequately, causing symptoms such as runny, frothy poo (sometimes green in colour), irritability and passing wind.

Human breastmilk contains approximately seven per cent lactose. There is actually no correlation between the amount of lactose in the mother’s diet and the amount of lactose found in her breastmilk. Therefore, eating a lactose-free diet yourself will not reduce the amount of lactose in your breastmilk.

In very rare cases, babies are born with a primary lactose intolerance. Babies who suffer from this type of lactose intolerance do not gain any weight and shows signs of dehydration soon after birth. Babies can also develop secondary lactose intolerance if there is damage to the lining of the gut (where the body produces the enzyme lactase). Secondary lactose intolerance can occur after a bout of gastroenteritis, from food intolerance or allergies, and coeliac disease.

If your baby has put on weight he obviously does not have primary lactose intolerance. If his poos seem fine and are not runny or frothy then it sounds as though he also does not have secondary lactose intolerance and that his unsettledness might be due to other factors.

It is common for new babies to be unsettled, especially in the first few months. On average a new baby cries for about three hours a day. The crying is often concentrated in the late afternoon or early evening (often referred to as the witching hour). Babies cry as a form of communication and so can cry for a variety of different reasons, hungry, wet, cold or tired. You might find it helpful to look at the Raising Children Network’s website: The website includes lots of information on newborns, including crying and settling issues. The website also has an online program called Cry Baby, which gives tried and tested strategies for managing sleep and crying in babies under 12 weeks old.

If these techniques don’t help and your baby’s unsettled episodes are increasing or you are finding it difficult to cope, see your doctor or child health nurse. Alternatively, you can talk to one of our midwives on the Health Information Line (numbers below).

Last updated: June 2016

© Women's Health Queensland Wide Inc. This article was published in Health Journey Issue 2 2016.


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