Have you wondered about which food chemicals cause most reactions? Of 100 people who react to artificial colours and flavours, 87 still reacted to flavoured but uncoloured lollies, and 87 reacted to chocolate (even though cocoa was allowed in the Feingold Diet, that started the thinking about additives back in the 1970s). 80% reacted to tomato sauce, 77% reacted to smells, especially paint and petrol, and 69% to perfume, especially to bubble bath, 67% had symptoms get worse when they had an infection, and 65% reacted to soy sauce. Now we know that soy sauce contains monosodium glutamate but is also high in amines.
57% reacted to the benzoate preservative in naturally flavoured canned lemonade when they did not react to the naturally flavoured, non preserved Schweppes lemonade in plastic bottles. 53% reacted to the BHA or BHT preservatives in oils. (Nowadays oils no longer contain these.) 49% reacted to the nitrate in bacon or ham. (There would be amines there too.) 44% reacted to Vegemite (high in amines). 44% reacted to natural lemon flavour in the Schweppes in plastic bottles (so these did not even get to test for the benzoate preservative in the canned produce).
43% reacted to carob powder in home cooking. 42% challenged with mint toothpaste but reacted. 37% reacted to lemon juice cordial with sulphite preservative, but not to home-made. 30% reacted to propionate preservative in bread. 28% reacted to vanilla in all natural ice cream, but note that 27% reacted to plain ice cream with artificial vanillin flavour (so the reaction is to the flavour itself), and 17% reacted to natural coloured margarine.
These reactions were found in the detailed study of 113 families followed up very carefully over 18 months for my Masters Degree. This had followed up a study of 500 families published in the Australian Journal of Dietetics.
It is interesting to look back at what needed to be clarified in the 1980s and 1990s. Now more information on the risk of a reaction to over 300 foods is available in my book Tolerating Troublesome Foods http://www.foodintolerancepro.com/tolerating-troublesome-foods/
You can read about much of my research in the section called Evidence Base in the Articles section on my website especially about Basic and Applied research in http://foodintolerancepro.com/evidence-base-food-sensitivity/