PURPOSE OF REVIEW: A new syndrome responding to gluten-free diet and defined non-celiac gluten sensitivity entered the spectrum of gluten-related disorders, together with celiac disease and wheat allergy. However, its definition, prevalence, diagnosis, pathogenesis, treatment, and follow up are still controversial. The purpose of the review is to summarize the evidence and problems emerging from the current literature. RECENT FINDINGS: Direct implication of gluten in the onset of symptoms is often unproved as a low fermentable oligo-, di- and mono-saccharides and polyols diet or other components of cereals as wheat amylase trypsin inhibitor could be similarly involved. To date, no specific biomarkers or histological abnormalities confirm diagnosis, and only the self-reported response to gluten-free diet as well as a positive double blind placebo-gluten challenge characterizes these non-celiac, non-wheat allergic patients. Critical revision of published studies can offer practical indications in approaching this clinical topic and useful suggestions to standardize scientific researches.