What are the signs of dairy intolerance?

Dairy is good for us, right? Especially for babies and growing children. The public health message is that milk is vital for good health. But could this healthy food be making many of us sick?


Many adults, children and babies have trouble digesting dairy. However, the symptoms of an intolerance may not be obvious, and are often attributed to something else. Symptoms which we tend to accept as common or even ‘normal’ could be signs of dairy intolerance.

Signs of dairy intolerance in babies

Colic is considered ‘normal’ and eczema is usually treated with medical creams. Yet both of these are possible signs that formula milk or something in a mother’s breastmilk is causing problems.

In my experience, most health professionals are concerned with life-threatening food reactions only. I suspect that this is because a diet without cow’s milk is considered inadequate, and alternative formula milks are somewhat lacking and only to be used as a last resort.

There is also hope that as a baby gets older, their digestive system strengthens, immune system normalises and the problem will go away. Dietitians will try to train the body to accept dairy products by putting them back into the diet a little at a time. Sometimes this is successful, but other times it isn’t. It appears that all has gone well, but the child develops other health issues that are considered unrelated to dairy (see below) – when actually they are.

The issue of dairy intolerance is easier to address if you are breastfeeding your baby. You have control over what you eat and therefore what goes into your baby’s milk.

It’s not always easy to make big dietary changes when you are post-natal and sleep-deprived, but it’s worth it. However, you do need to be strict about elimination. Cutting out milk and leaving in cheese or ‘just’ having milk in cups of tea may not be enough. You need to cut it all out to find out for sure.

Signs of dairy intolerance in childhood

Remember I told you about the child who seemed to have outgrown their problem with dairy? The problem is now they suffer from lots of ‘normal’ childhood health issues:

  • repeated bouts of tonsillitis
  • ear infections
  • snoring
  • sleep apnoea
  • constant runny nose
  • bed wetting
  • joint pains
  • stomach aches
  • digestive issues (excess gas, constipation and/or diarrhoea)

There is a possibility that all of these symptoms could be linked to an unresolved dairy issue. The inflammation caused by keeping dairy products in the diet can affect immune system function.

These health issues are so common, we see them as a normal part of childhood. Often parents think their child has outgrown his or her dairy intolerance because their eczema or diarrhoea has passed, but now they have asthma or recurrent tonsillitis. This is a big red flag that they can’t tolerate dairy – all that has changed is their symptoms.

Eliminating whole food groups from the diet may concern you, especially when we have been programmed into thinking our child’s health won’t flourish without it. I suspect that if your child has problems digesting dairy that this may affect their ability to use and absorb nutrients. So careful removal under the guidance of a professional may actually improve their nutrient uptake and significantly boost their health.

Signs of dairy intolerance in adults

Adults with dairy issues might experience obvious digestive symptoms like reflux, wind and constipation and/or diarrhoea, but they might also exhibit less-obvious symptoms like recurrent sinusitis, urinary tract infections, fatigue and acne.

A causal relationship can become difficult to pinpoint because dairy is usually a regular feature in the diet and symptoms can take up to 48 hours to appear. This can leave you suffering from regular aches and pains with no obvious known cause. Looking in your history for the types of ailments mentioned above might give you a clue.

Food intolerance testing and elimination diets

You can run a food intolerance test to find out if there is a dairy intolerance present. This can’t be used on children under the age of two. Another option is to try a full elimination diet for four to six weeks. The elimination diet should be strict with every type of dairy taken out of the diet and all labels should be scrutinised.

I should mention that at this point, goat’s and sheep’s milk should be avoided, too. They have similar proteins and around 70% of people that react to cow’s milk react, to goat’s milk too.

Initially, the avoidance of dairy should provide some relief from your symptoms. If your symptoms have been with you for a long time then it may take a while to get some relief. The important thing to note is what happens when you add dairy back into the diet after six to eight weeks of complete avoidance.

Within 48 hours of its re-introduction, you will probably get a strong reaction, with more noticeable symptoms. It is this re-introduction that tells us whether dairy is a problem for you.

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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Birmingham, B13 8JP
Written by Sarah Hanratty
Birmingham, B13 8JP

Sarah is an experienced practitioner at the Brain Food Clinic specialising in the link between gut function and cognitive well-being.

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