What is the difference between milk allergy and milk intolerance?

I am confused between the terms milk allergy and milk, or lactose, intolerance. Could somebody shed light on this?

[CherieLu]

There is a lot of confusion between the terms milk allergy and milk, or lactose, intolerance. Milk allergy is when your baby's immune system reacts to proteins in milk. It is the most common childhood allergy, affecting between two per cent and seven per cent of babies (may 2009). Lactose intolerance is when your baby has difficulty digesting the lactose, or the sugar, found in milk. This is much rare than milk allergy.

Your baby can take in milk protein through your breast milk if you have drunk or eaten dairy produce, or she might react to cow's milk-based formula milk. Babies can be allergic to casein in milk (the curd formed when milk turns sour), the whey (the watery part left when the curd is removed), or both. Most children will have grown out of their milk allergy by the time they are three. If your baby is allergic she could have an immediate reaction after drinking milk or eating something with a dairy ingredient. Her face will flush and show a rash, and she's likely to have watery eyes and a stuffy nose. It's also possible she'll feel sick or have diarrhea. Most allergic reactions to milk are immediate, but delayed allergic reactions are common too. Remember that these symptoms are common in early childhood and an allergy is only one possible explanation.

It will be more tricky to find out whether your baby is having delayed allergic reactions, because they involve parts of the immune system that take longer to respond. Your doctor and a dietitian will work with you on a diet that cuts out milk from your baby's meals. This can be a long process, during which the dietitian will review your baby's symptoms and gradually reintroduce milk to her diet to see if the symptoms recur. Always see your doctor or a dietitian before cutting food groups out of your baby's diet.

If your baby has a lactose intolerance, this is a quite a different condition to an allergy. It means she has difficulty digesting lactose, the sugar found in milk. It is likely that she will lack the enzyme, lactase, needed to break down lactose. It's rare for babies in the UK to be born with lactose intolerance, although it is more common in parts of the world where adults don't typically drink or cook with cow's milk, for example, in Asia, Africa and South America. More on this articule in babycenter.co.uk