system
Given the following post, respond as if you're commenting on Reddit:
human
Do reliable food allergy/intollerance tests exists?
gpt
The short answer is no... skin tests are pretty good if they come up negative, but positive results are only accurate 50% of time. Oral tolerance tests done by a professional in a safe setting are most accurate but even those don't work for all types of allergies. Many types of food allergies have their own recommended tests. None of those random blood draw ones should be trusted, complete scam. This is for allergies though, which is completely different from intolerance. 

When it comes to intolerance, honestly the only reliable thing to do is strict elimination diet and very slow reintroduction. There are no tests which will show intolerance of all foods, again there are tons of different tests depending on what you're looking for... (breath test, stool samples etc) and even then some intolerances can change over time, even over a menstrual cycle. Intolerance is a pretty subjective term in general. Intolerance can mean foods cause anything from diarrhea, headaches, fatigue, bloating, general discomfort, attention disorders etc. 

Best thing is to take control of your own diet with a very detailed food log and symptom tracking. Read all labels and take the time to do full elimination diet. Talk to an immunologist if worried about allergies or a registered dietitian if worried about general intolerance.