I don't eat pork, but even if I did I wouldn't touch ham with a ten-foot pole.  It's aged... it's smoked... and it's often loaded with nitrites to kill bacteria (which kill the bacteria in your GI system too).  Find another source of salt to satisfy your craving!!  I recently bought a little grinder of "Himalayan pink salt."  Kind of spendy, but it's so pretty and it makes my plain, salted rice seem like a treat

Heather

I've eaten the turkey.  Sometimes it was okay, and sometimes not.  If they are pre-cooked, they very likely have a lot higher histamine than fresh meat you cook at home.  I stay away from them now.  Just not worth the possible reaction.

The expiration date on a package of lunch meat refers to an unopened, factory sealed package.  I just read that, once opened, lunch meats should be used within 3-4 days after opening if they were in a factory sealed package.  If bought at the deli and sliced there, then 2-3 days.  As a masto patient, if you must eat them, I would stay with the shortest period of time possible.  

Do check the ingredients for things that could cause a problem, such as curing ingredients or other preservatives.

If you are going to try them go with jbean and joan's advise. The nitrate free/chemical free ones. Make sure to read though, even health food stores carry stuff with crap in it! A lot of these meats have celery juice in them for flavor additive so read read read. Applegate farms is a brand that makes a lot of variety. I think they have at least two different ham versions. The roast beef has pepper in it so that one is out for me. I'm like Joan and can occasionally have the turkey. However I cannot have under any circumstance a turkey that is not chemical free, Phosphates and Nitrates will send me to the hospital asap. It's amazing what can fall under the word "natural" now. So read read read!  and like Joan said, sometimes I just can't do it. I was getting natural breast and cooking it and freezing it. But it seems like I tolerate it so very rarely it's no longer worth the bother. So test but test smartly! I've gotten away with Neiman Ranch nitrate free bacon I think the maple syrup one, not all the time but sometimes. Celery will send me to the ER also, but for some reason I can have the "juice" thats sometimes in these. Again.... that word sometimes. If I juiced a celery it'd put me in the ER, If you tolerate it, wait two weeks then try again. Most Health food lunchmeats are vacuum packed real food unlike the deli counter lunchmeat people think of!