In this case, a marked but partial improvement is an acceptable sign of food playing a part in causing the illness. If someone has food intolerance, then the exclusion phase will produce a sudden and utterly exhilarating return to health. It's like getting my life back again' said another. Those who have been struggling on for years with food intolerance are invariably amazed at what it is like to actually lose the symptoms. Anyone who has experienced such an improvement will be highly motivated to carry on with the reintroduction phase, despite the fact that it is quite arduous.
Foods have to be reintroduced one at a time, with a space between in which symptoms can be observed.
It sounds simple, but don't be deceived. This is where errors can easily occur. The portions have to be large enough. The interval between testing foods needs to be just right. The form in which you test the foods needs to be just right.