I did the LEAP – MRT food sensitivity test earlier this year which is done by a blood draw. It gives you a line by line of 250+ foods and how your body responds to them. If your doctor is familiar with it, they can prescribe it for you at a lower cost. But sadly, most do not so I went through <firstname.lastname@example.org>. For me it was totally worth it – I had extreme stomach aches for years and after doing every test (endoscopy included with a GI) I now do not have constant stomach upset/pain/gas/discomfort since I know what foods, oils and spices, etc. to avoid!