Food intolerance is just a less severe type of allergy

Food allergy and intolerance are quite different. A food allergy is a reaction produced by the body’s immune system when it encounters a normally harmless foodstuff. This tends to happen relatively quickly and will happen with even a tiny amount of that food. An intolerance doesn’t usually involve the immune system at all. It is when a foodstuff causes an unpleasant reaction, such as diarrhoea. Effects are rarely immediate and people with an intolerance may still be able to eat that foodstuff in small quantities.