Can food allergies be inherited?

Chris Smith asked geneticist Giles Yeo from Cambridge University to break down this question from James in Oxford.

Giles - The answer is yes, but it’s more complicated than that. The first thing I want to do is that there’s a big difference between “intolerance” and “allergy.” An intolerance is almost like you can be lactose intolerant because you lack the enzyme to break down lactose. An allergy is when you have an immune response to the protein within milk, for example, for milk allergy. An intolerance can be inherited and that’s almost going to be mendelian. So, for example, because a very specific gene needs to break down alcohol and needs to break down lactose and that’s inherited. Allergy is more complicated because it’s an immune response. So while there is a genetic element to it, it’s not like Mendel's peas. You can’t say for sure if my parents were allergic then I’m going to be allergic, so there is a genetic element to it but it is not mendelian. So, in other words, it’s not for sure that you’re going to inherit it if your parents happen to be allergic to a given product or item.