The gluten-free movement leaves researchers, clinicians and nutrition professionals with many unanswered questions, especially how to best help those who do not have celiac disease—an autoimmune ailment linking gluten to severe intestinal damage—but who experience similar symptoms. An updated review on celiac disease and nonceliac gluten sensitivity published in the Journal of the American Medical Association offers new insights.
Until recently, celiac disease and wheat allergy were thought to be the primary conditions causing the gastrointestinal discomfort that many people attribute to gluten, a protein in wheat, barley and rye. But now the condition known as nonceliac gluten sensitivity is better understood. Nonceliac gluten sensitivity applies to those who do not have celiac disease, wheat allergy or irritable bowel syndrome but do have clinical symptoms such as abdominal pain, bloating, constipation, diarrhea, flatulence, anxiety and depression, fatigue, eczema, irritability, anemia, headache, or joint, muscle and nerve pain, all of which seem to improve in response to a gluten-free diet. (People with irritable bowel syndrome may experience fewer symptoms on a gluten-free diet because they’re eating fewer gluten-containing cereals, which tend to be high in the highly fermentable but poorly absorbed FODMAPS (fermentable oligosaccharides, disaccharides, monosaccharides and polyols).
There is no blood test to confirm nonceliac gluten sensitivity. The diagnosis depends on ruling out celiac disease and wheat allergy and seeing a notable improvement in symptoms within 1 week of removing gluten from the diet. The treatment for all gluten-related conditions is the same: Avoid gluten. But for how long that is necessary depends on the underlying problem. Nonceliac gluten sensitivity can be a transient condition, whereas celiac disease is lifelong. Experts recommend that people with nonceliac gluten sensitivity adhere to a gluten-free diet for a period of time, typically 1–2 years, before retesting their gluten tolerance with a 1-week exposure to gluten. For many people, the earlier symptoms will not recur, and they can safely incorporate gluten into their diets.
Note that the review authors state that “there is no scientific evidence to suggest that a gluten-free diet is part of a healthier lifestyle or can be helpful to treat overweight or obesity.”