Fat-free, Sugar-free, and now Gluten-free?

Stacey Penney
Stacey Penney
| Stay Updated with NASM!

Are your nutrition clients going gluten-free? This topic is sure to cause some strong opinions and sharing of stories of how a gluten-free diet has changed someone’s life. The goal here is to share some of the details regarding gluten, who really needs to cut gluten from their diets, and the challenges that accompany a gluten-free diet.

Gluten is a protein found in wheat, barley, and rye (1). Oats also contain similar protein complexes, but their classification is a bit in the gray since most oats are cross-contaminated with gluten by the time they reach the consumer due to harvesting and processing methods. While there are some oat products available that have avoided cross-contamination, vigilance and a deeper inquiry into the product is key for those with a sensitivity to gluten.

Some of the more common ingredient key words that may indicate they contain gluten, beyond wheat, barley, rye, and oats, include brewer’s yeast, bulgar, durum, faro, hordeum vulgare, kamut, malt, secale, seitan, semolina, triticale, and triticum vulgare (2-3). You may also have to connect with manufactures to see if their natural flavorings, colorings, thickeners or emulsifiers contain gluten (3). Keep in mind that product recipes change, so check the ingredient labels regularly.

The U.S. Food and Drug Administration (FDA) does not currently have a standardized definition to regulate the “gluten-free” claim seen popping up on product labels across store shelves, even on products that were never a concern for the presence of gluten (4). The FDA is also questioning the “gluten- free” label claim and how it effects buying choices when compared to other products with the same ingredients but not labeled gluten-free. Are your personal buying choices swayed into thinking the product labeled gluten-free is healthier? Hopefully gluten-free is not taking us down the same consumer choice manipulating paths as sugar-free, reduced-fat, high-protein, and high-fiber labels have.

Who needs to avoid gluten? For those with the autoimmune disorder called celiac disease, avoiding gluten is essential. Affecting anywhere between 1 out of 100 to 1 out of 500 people worldwide, celiac disease involves the inability to digest gluten (1,5). When intestinal villi are exposed to gluten they become inflamed. If left untreated, this can cause flattening of the villi in the intestine, leading to a mal-absorption of nutrients, including iron, vitamin D and calcium (1,6).

A lack of iron can lead to anemia and a potentially adverse impact on physical and mental functioning, while the low levels of calcium and vitamin D can lead to osteoporosis and poor bone health (6-7). The only effective treatment for celiac disease is following a life-long gluten-free diet.

A more controversial gluten challenge is gluten sensitivity or gluten intolerance. So far there hasn’t been a definitive agreement on whether it is a medial condition or not. The symptoms of gluten intolerance and celiac disease are almost identical. Not to debate with the medical experts on its condition status, those who receive negative results on celiac disease screening test typically find a gluten-free diet helps relieve their symptoms.

Many consumers follow a gluten-free diet whether they are or are not allergic to gluten. From a nutritional standpoint, there is no reason not to eat gluten if you're not "gluten sensitive or allergic." I recommend all of my clients get tested if they are having GI issues before following any specific diet.”  Courtney Walberg, RD, NASM-CPT

Luckily for most of us there is not a serious medical reason to restrict gluten from our diets. Removing gluten-containing foods can be a convenience challenge, and as with most restrictive diet plans, there is a high failure rate. Many of the processed, packaged foods that we rely on contain gluten. If going gluten-free, focus on replacing these carbohydrate-rich convenience foods with gluten-free alternatives containing rice, corn meal, potatoes, nuts, and of course, fruits and vegetables (6). Many people without celiac disease feel better by removing over-processed foods, gluten containing or not, from their diet because of anti-inflammatory benefits gained.

For those with celiac disease, working with a registered dietitian is essential to make sure they are getting the nutrients they need and identifying potential sources of gluten, including those found in some nutritional supplements and medications.

See An Introduction to 4 Popular Diets for more info on Gluten-free diets. And check out the NASM Navigating Diets course for a broader overview of diets in general.


  1. Insel P., Ross D., McMahon K., et al. Nutrition. 4th ed. Sudbury, MA: Jones and Bartlett; 2011.
  2. Case, S. Gluten-Free Diet: A Comprehensive Resource Guide, Expanded Edition. Case Nutrition Consulting; 2006.
  3. Anderson, J. What Terms Mean 'Gluten' on Food Labels? Guide. 10.23.2011
  4. Public Meeting: Gluten-Free Food Labeling. N.p., 19 Aug. 2005. Web. 23 June 2013.
  5. Keihanian, S. Burke, K., Levey, J. Sports dietary supplements: overview and effect on the gluten-sensitive athlete. American Medical Athletic Association Journal. 2010; 23(3)10-12.
  6. Mancini, L., Trojian, T., Manicni, A. Celiac disease and the athlete. Current Sports Medicine Reports, 2011;10(2)105-9.
  7. Clark, M. NASM Essentials of Personal Fitness Training 4th ed. Baltimore, MD: Lippincott Williams & Wilkins; 2012.

The Author

Stacey Penney

Stacey Penney

Stacey Penney, MS, NASM-CPT, CES, PES, CNC, is the Content Strategist with NASM and AFAA. A 20+ year veteran of the fitness industry, she's worked with the top certification and continuing education groups. At NASM and AFAA she drives the content for American Fitness Magazine, blog and the social media platforms. Stacey received her degree in Athletic Training/PE from San Diego State University and an MS in Exercise Science from CalU, plus credentials in Health Promotion Management & Consulting (UCSD), Instructional Technology (SDSU), group fitness and yoga. Previous San Diego Fall Prevention Task Force Chair, she’s developed continuing education curriculum for fitness organizations in addition to personal training, writing, and co-coaching youth rec soccer.


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