Breastfeeding Baby With Dairy Allergy

I received an email today asking a delicate question.

I was wondering if you could help. If my baby has a milk protein allergy (she is breastfed) can I eat products that are non-dairy but with added lactose such as deli meat?

This is a question I had to tiptoe very carefully around. I answered:

Pure lactose will not affect someone who has a dairy allergy, which is to the dairy protein. Breastmilk itself is 7% lactose, so any additional lactose in the diet wouldn't be even noticed.

If the additive in the deli meat is some other milk product then you should check with a doctor first.

A few people are so sensitive to dairy proteins that the slight possibility that lactose may have a few molecules of protein in it is enough to make them avoid lactose entirely. These have always been people who take milk in directly. I've never heard of a case in which dairy protein reached a breastfeeding child via lactose in the mother's diet. But I also don't know how seriously allergic your daughter is.

I'd say it's very unlikely for the normal allergic baby to be affected in this manner. But I don't know the particulars of your case. Your doctor does. I would doublecheck the next time you visit.

Sensitivities to protein vary enormously. That's why it's so important to get all the information possible on your specific case - or for your own child's - to be able to make the most informed decisions about diet.