Why does one develop a food allergy later in life when it wasn't present as a child

your body goes through changes every seven years therefore you can develop allergies to some foods that you never had before l was lactose intolerant and now can drink milk
its a weird world !!!!

The food allergy was probably their, just not reactive.sometimes eating too much of a food can freak the body out and cause dislike of the food and sometimes even an allergic reaction. l used to eat a lot of chinese food when l grew up (like 3 times a week) now l almost never eat it because l started getting severe allergic reactions to the MSG (a spice that is used on lots of foods, not just chinese foods).