I think he meant an over time aquired food allergy. Esp. Older folks seem to get them -like me- one can test with a Serum specific IgE in vitro Test. There are over the counter test one can buy relatively cheap.

I did one recently, turned out I was allergic to garlic of all things (among others). Advice is to stay off it for 4-6 months then slowly reintroduce. Life is wild sometimes.