I think PB&J is a brand or expression that is only familiar to Americans, so you'd better explain it. I don't know what it means and can't be fussed to google it.

There is something about our lifestyle and environment that makes people more allergic today than in the past. I think it's a very important matter to get to the bottom of. Some allergies are deadly and it affects people's life very negatively.

I have something called an auto-immune disease (the body is allergic to something in itself). I hate to talk about it and won't, but suffice to say it has caused me a lot of suffering throughout my life.

edit - figured out what cappecoddah's acronym stands for. Peanut butter and Jelly sandwich (jelly is jam, I am guessing, but what type)