Do I need to fast or avoid certain foods before my food sensitivity test?
No, it is not necessary to fast prior to your food sensitivity test. It is also not necessary to adjust your diet in any way prior to your test. The food sensitivity test involves taking your blood and exposing it to various foods to assess for an immune reaction generating certain types of antibodies.
The antibodies being testing are called IgG. As long as you have eaten a certain food within the past 4 weeks, the test should be able to detect those IgG levels. Conversely, if someone has removed a food from their diet for long periods of time, they may or may not still have IgG reactivity detected. In general, your body will clear specific IgG antibodies not being triggered by certain foods 18 to 24 months after last exposure; however, people have been known to clear IgG both sooner and longer than those times intervals.