NCGs

NCGS, or non-celiac gluten sensitivity, is a condition in which individuals experience gastrointestinal and/or extraintestinal symptoms after consuming gluten, but do not have celiac disease or wheat allergy. Its status as a distinct medical entity is debated, and no reliable biomarker has been established.

Symptoms commonly include abdominal pain, bloating, diarrhea or constipation, headaches, fatigue, joint or muscle pain, foggy thinking, and other nonspecific complaints. Symptom onset is typically rapid after gluten ingestion and improves on a gluten-free diet; symptoms may recur with gluten reintroduction in controlled settings.

Diagnosis is one of exclusion. Clinicians rule out celiac disease (negative celiac serology and often normal intestinal biopsies) and wheat allergy (negative IgE testing). A therapeutic trial of a gluten-free diet with symptom improvement supports the diagnosis, often followed by a controlled gluten challenge to confirm. However, there is no universally accepted diagnostic test.

Pathophysiology is not well understood. Hypothesized mechanisms include innate immune responses to gluten, changes in intestinal permeability, and the possible contribution of other dietary components such as fermentable carbohydrates. The role of amylase-trypsin inhibitors has been proposed.

Management centers on a nutritionally adequate gluten-free diet tailored to the individual. Some patients may benefit from a reduced intake of fermentable carbohydrates (low-FODMAP diet) or from addressing coexisting conditions. Ongoing research aims to clarify prevalence, mechanisms, and long-term outcomes.