It is an Allergy or an Intolerance?
In a milk allergy, the body reacts to milk proteins, not milk sugar.
In lactose intolerance, there is little to no lactase (an enzyme produced by our body), so the milk sugar (lactose) cannot be digested.
Cow's milk protein allergy (CMPA) affects from 2 to 6% of children, with the highest prevalence during the first year of age.
Lactose intolerance has 4 types:
The tests for both are different.
Obviously, the symptoms are also different.
If you or your child have an immediate reaction to a food, avoid it and ask for a referral to either a Paediatric Allergist or an Adult Allergist.
In case the reactions are delayed (2 hours to several days), your best option is to be seen by either a Paediatric Dietitian or an Adult Dietitian.
Dr Costa is a Consultant Paediatrician and fellow of the Royal College of Paediatrics and Child Health.