My daughter suddenly had a severe reaction to all food, hers was pretty strong causing an all over skin rash with swelling, so pretty scary stuff that landed her in hospital and using an epi pen. She was given strong antibiotics, the Dr. thought it could have been Lyme. She is a lot better now but still has quite a few sensitivities, as do I. So I think it can be a lot of things that can cause it.
Started Primal June 2012 at 148.5lbs, and 5' 1", reached goal weight in 5 months.
Lowest weight 93lbs - too thin. Now stable at 102lbs much better weight for me at my age.
Primal, minus eggs, dairy and a myriad of other allergens.