It is estimated that 18 million Americans have gluten sensitivity--six times the number of Americans who have celiac disease (BeyondCeliac.org: Non-Celiac Gluten Sensitivity, 2015B). Gluten-free diets are prescribed for those who have undergone rigorous testing and are ultimately diagnosed with a gluten allergy. However, there is growing public interest in gluten-free diets which has launched U.S. retail sales of gluten-free products. In 2015, retail sales reached $10.5 billion dollars and it is projected by 2020 the market will be valued at $23.9 billion (Statista, n.d.).

What is Gluten?

Gluten is the group name for two proteins, gliadin, and glutenin, which are primarily derived from wheat, barley, rye, and triticale. These proteins are responsible for the bonding of particles, giving food its shape.

How Does Gluten Affect the Body?

When gluten is consumed, those with an allergy experience an immune response that attacks the small intestine. Once the villi of the small intestine are damaged, nutrients cannot be properly absorbed. There are over 300 symptoms associated with a gluten allergy. While some people may be asymptomatic throughout their lifetime, many experiences at least some of the wide variety of symptoms. These symptoms can range from depression and anxiety to weight loss, fatigue, chronic diarrhea, constipation, migraines, and dermatitis (Celiac.org, 2016A).

Celiac Disease & Non-celiac Gluten Sensitivity (NCGS)

While there are multiple blood tests available to detect celiac disease antibodies, the most commonly used is a tTG-IgA test. If antibodies are present, either an endoscopic or skin biopsy is performed for confirmation (Celiac.org, 2016B). Celiac disease is hereditary and affects both males and females of all ages and races. It often goes undiagnosed or is commonly misdiagnosed by providers. An estimated 1 in 133 Americans, or nearly 1% of the population, has celiac disease (BeyondCeliac.org: Celiac Disease, 2015A).

Recent research shows there is no evidence to support an increased risk of celiac disease when infants are introduced to gluten at an early age (<4 months). However, delayed introduction (>7 months) to gluten may be associated with an increased risk (Pinto-Sánchez, et al., 2016).

Non-celiac gluten sensitivity (NCGS) may present with similar signs and symptoms as celiac disease, however, the tTG antibodies are not present and symptom relief is noted in the absence of gluten. There is no cure for gluten sensitivity, only the recommendation to follow a gluten-free diet (Catassi, et al., 2015).

Gluten-free Diets

Removing gluten from one’s diet is no easy feat. Reading labels and understanding where gluten may be hiding takes time and education. Products such as lotions, cosmetics, cleansers, and medications may contain gluten proteins. Gluten-free products are typically more expensive, and, while varieties of foods and products are expanding, there are still considerably fewer choices for gluten-sensitive consumers.

Adherence to a gluten-free diet has been shown to improve physiological changes in intestinal villi and a decrease in tTG antibodies among asymptomatic patients diagnosed with celiac disease (Kurppa, et al., 2014).

While there is considerable evidence to support the benefits of a gluten-free diet, the medical community warns against it, if not deemed medically necessary. Removing gluten from one’s diet can not only reduce the intake of essential vitamins and minerals which are found in fortified foods, but it can also reduce the number of probiotics in the gut which boost the immune system (University of Wisconsin Health, 2016). Support from a provider or registered dietician is highly recommended to ensure all nutritional needs are met.

Resources Available

Scientific studies on gluten sensitivity, gluten-free diets, wheat allergies and celiac disease have rapidly increased over the past decade. Some of this new research can be found in the following sources:
Beyond Celiac
Celiac Disease Foundation
The North American Society for the Study of Celiac Disease

As interest in gluten-related health concerns grows, consumers should be encouraged to talk with their providers about their concerns and together identify the next steps to take.

References
BeyondCeliac.org. (2015A). Celiac Disease: Fast Facts.
BeyondCeliac.org. (2015B). Non-Celiac Gluten Sensitivity. 
Catassi, C., Elli, L., Bonaz, B., Bouma, G., Carroccio, A., Castillejo, G., ... & Dieterich, W. (2015). Diagnosis of non-celiac gluten sensitivity (NCGS): the Salerno Experts’ Criteria. Nutrients, 7(6), 4966-4977.
Celiac.org. (2016A). What is celiac disease? 
Celiac.org. (2016B). Diagnosis. Retrieved from: https://celiac.org/celiac-disease/diagnosing-celiac-disease/diagnosis/
Kurppa, K., Paavola, A., Collin, P., Sievänen, H., Laurila, K., Huhtala, H., ... & Kaukinen, K. (2014). Benefits of a gluten-free diet for asymptomatic patients with serologic markers of celiac disease. Gastroenterology, 147(3), 610-617.
Pinto-Sánchez, M. I., Verdu, E. F., Liu, E., Bercik, P., Green, P. H., Murray, J. A., ... & Moayyedi, P. (2016). Gluten introduction to infant feeding and risk of celiac disease: systematic review and meta-analysis. The Journal of Pediatrics, 168, 132-143.
Statista. (n.d.). Statistics and facts on the gluten-free foods market in the U.S. 
University of Wisconsin Health. (2016). The reality behind gluten-free diets.