Do not perform food intolerance tests except for those scientifically validated

Type of practice

Other tests

Topic Area


The only validated diagnostic test is lactose breath-test for lactose intolerance. Others test such as VEGA-test, Cytotoxic test, serum specific IgG4 determination, hair analysis, intestinal permeability, salivary IgA, “bioresonance” techniques, fecal microbial analysis and fecal short-chain fatty acids are unvalidated, expensive and can lead patients to inappropriate and potentially harmful diets, with no benefit on their symptoms. The results of such tests may be inconsistent and there is lack of evidence to support their use in clinical practice.


1. Gargano D, Appanna R, Santonicola A, et al. Food Allergy and Intolerance: A Narrative Review on Nutritional Concerns. Nutrients 2021;13:1638
2. Boyce JA, Assa'ad A, Burks AW, et al. Guidelines for the Diagnosis and Management of Food Allergy in the United States: Summary of the NIAID-Sponsored Expert Panel Report. J Allergy Clin Immunol 2010;126:1105-1118
3. DeGeeter C, Guandalini S. Food Sensitivities: Fact Versus Fiction. Gastroenterol Clin North Am 2018;47:895-908
4. Tuck CJ, Biesiekierski JR, Schmid-Grendelmeier P, Pohl D. Food Intolerances. Nutrients 2019;11:1684



Attention. Please note that these items are provided only for information and are not intended as a substitute for consultation with a clinician. Patients with any specific questions about the items on this list or their individual situation should consult their clinician.