Lactose Intolerance vs Dairy Allergy – What is the difference ?
There’s a lot of confusion surrounding lactose intolerance and a dairy allergy — the terms may sound similar, but they actually describe two different problems, and one is more severe than the other.
Lactose intolerance ( a digestive system issue ) is caused by not having enough of the enzyme lactase, which helps to digest the milk sugar called lactose. Symptoms include diarrhoea, vomiting, stomach (abdominal) pain and gas (wind or bloating). This condition is uncomfortable but not dangerous and does not cause rashes or anaphylaxis. Lactose intolerance can be genetic or caused by damage to the small intestine due to viral, bacterial infection or antibiotics. Lactose intolerance increases with age and is quite common in the elderly.
Allergy tests to cow’s milk proteins are negative in people with a lactose intolerance.
Dairy allergy ( an immune system issue ) is a true food allergy caused by an allergic reaction to the protein in milk. It is most common in infants and children. Dairy allergy used to only refer to cow’s milk but with the substantial rise in allergies we are now seeing other milks such as goat, sheep, soy and tree nut milks which may also trigger a reactions.
An allergic reaction to cow’s milk usually begins within minutes up to a couple of hours.
A dairy allergy can also cause a reaction in other parts of your body, including the skin and lungs:
- Swelling, often in the lips and face
- Tightness in throat
- Trouble swallowing
Sometimes, if the reaction is mild it is not possible to immediately differentiate between the two. If in doubt, we have lab tests to help make the diagnosis.