During the past decade there has been an impressive increase in popularity of the gluten-free diet (GFD), now the most trendy alimentary habit in the United States and other countries. According to recent surveys, as many as 100 million Americans will consume gluten-free products within a year.
According to traditional medicine approach GFD benefits only individuals with celiac disease (less than 1% of the population).
However, apart from unfounded trends, a disorder related to ingestion of gluten or gluten-containing cereals, namely non-celiac gluten sensitivity (NCGS), has resurfaced in the medical literature (the first case was described in 1978). There is an ongoing debate on the appropriateness of the GFD for people without celiac disease. Although there is clearly a fad component to the popularity of the GFD, there is also undisputable and increasing evidence for NCGS as a real clinical entity.

• What is Gluten?
  Gluten is the main storage protein in wheat barley and rye. Wheat is the most widely grown crop worldwide, with more than 25.000 different varieties. Its popularity results from its simplicity of cultivation in different climates, high yield, and good nutritional value. Furthermore, the functional properties of gluten proteins have led to their addition to many foods and cosmetics.
• What diseases are associated with gluten?
  Gluten related diseases are activated by the ingestion of gluten containing cereals (wheat, barley and rye) by people with a genetic and/or immunologic predisposition.
  The two well defined clinical entities in relation with gluten ingestion are: wheat allergy and celiac disease. Both are mediated by the adaptive immune system
  

  • In wheat allergy the mechanism involves IgE as in all other allergies.
  • Celiac disease, has characteristics of an autoimmune disorder

  
  In addition to celiac disease and wheat allergy, there have been cases of reactions to gluten-containing grains that involved neither allergic nor autoimmune mechanisms. These generally are termed non celiac gluten sensitivity (NCGS) or simply gluten sensitivity. The current evidence points that in NCGS the innate immune system is also involved.
• What are the symptoms of NCGS?
  Symptoms of NCGS usually occur within hours or days after ingestion of gluten-containing grains, and disappear rapidly when these grains are eliminated from the diet.
  NCGS most frequently produces a combination of intestinal and extra-intestinal symptoms.
  Irritable Bowel Syndrome-like symptoms, such as abdominal pain, gas, distension, and irregular bowel movements, frequently are reported and therefore make it difficult to distinguish NCGS from IBS induced by other causes.
  The differential diagnosis is facilitated for patients who also experience extra intestinal symptoms, including headache or frank migraine, foggy mind, chronic fatigue, joint and muscle pain, tingling of the extremities, leg or arm numbness. eczema, anemia, depression or for patients who report a reduction in autoimmune symptoms on a GFD.
• What are the symptoms of NCGS?
  Symptoms of NCGS usually occur within hours or days after ingestion of gluten-containing grains, and disappear rapidly when these grains are eliminated from the diet.
  NCGS most frequently produces a combination of intestinal and extra-intestinal symptoms.
  Irritable Bowel Syndrome-like symptoms, such as abdominal pain, gas, distension, and irregular bowel movements, frequently are reported and therefore make it difficult to distinguish NCGS from IBS induced by other causes.
  The differential diagnosis is facilitated for patients who also experience extra intestinal symptoms, including headache or frank migraine, foggy mind, chronic fatigue, joint and muscle pain, tingling of the extremities, leg or arm numbness. eczema, anemia, depression or for patients who report a reduction in autoimmune symptoms on a GFD.
• What is the difference between intolerance and sensitivity?
  • Food intolerance occurs when the body lacks a particular enzyme to digest nutrients, or for other reasons a particular nutrient cannot be digested properly. Symptoms are exclusively GI and mostly secondary to sugar fermentation by the intestinal microbiota, leading to the production of gas, which causes abdominal distention, abdominal pain, and irregular bowel movements. Common examples include lactose intolerance.
  • Food sensitivities are immune mediated reactions to some nutrients involving the GI tract. They can also involve extra intestinal symptoms and frequently do not always occur with the same pattern. Common examples include reactions to nuts fruits and selfish.
• How do you make the diagnosis?
  At this moment, apart from a few tests that are used only in research, NCGS is an diagnosis of exclusion based on the following criteria:
  

  • You have to exclude celiac disease and wheat allergy with simple blood tests.
  • The intestinal and/or extra intestinal symptoms resolve once the gluten-containing foodstuffs are eliminated from the diet.
• What treatments are available?
  At this moment the treatment consists in avoiding all gluten containing foods.

Points to remember:

• NCGS is a ill defined but real clinical entity.
• It can cause symptoms on the GI tract.
• It can also cause headache, migraine, foggy mind, chronic fatigue, joint and muscle pain, tingling of the extremities, leg or arm numbness. eczema, anemia, depression and autoimmune problems.
• The diagnosis is not straightforward and necessitates both blood tests and a period of gluten free diet.