By, Maria L. Urso, PhD – O2X Nutrition Specialist
In 2022, the gluten-free product market size was estimated to be nearly 7 billion dollars. That number is expected to rise to 10 billion in the next five years. To put this into perspective, the fruit and vegetable market size was approximately 93 billion in 2022, and that number is not expected to increase much in the next five years. These staggering statistics beg the question: why have we become so gluten averse?
What is Gluten anyway?
Gluten is a general name for the proteins found in wheat. Foods that contain wheat such as wheatberries, durum, emmer, semolina, spelt, farina, farro, graham, rye, barley, and triticale contain gluten. Oats do not naturally contain gluten, but some oats are produced using gluten-containing ingredients. Gluten is a “sticky” protein, so it acts as a glue in many foods, helping them to maintain their shape. This is why gluten or wheat-based ingredients are used in so many recipes- from cookies to licorice.
Why is Gluten in the hot seat?
From the second food enters our mouths, various enzymes get to work to help break down the food during digestion. For example, amylase helps to break down starches in the mouth, while lactase helps to break down the proteins found in milk in the small intestine. If you are lactose-intolerant, it usually means that your lactase enzymes are not able to break down the protein found in dairy. When it comes to most other proteins, including wheat, protease is the enzyme that helps our body digest these proteins. Protease is not able to fully break down gluten. In ~99% of the population, the remaining gluten goes to the small intestine, and it is eventually passed through the body with no issues. In individuals with Celiac disease, this undigested gluten in the small intestine triggers a severe autoimmune response or other unpleasant symptoms such as joint pain, diarrhea, headaches, and skin rashes. In people with Celiac disease, repeated exposure to gluten, and subsequent inflammatory reactions, can damage the small intestine resulting in malabsorption of many key nutrients.
While Celiac disease was a relatively rare and unknown condition, some people with gastrointestinal complaints found that when they followed an elimination diet, they tended to feel better if they did not eat foods that contain gluten. While many did not have a positive blood test or intestinal biopsy that pointed to Celiac disease, it was considered possible that they have small intestines that don’t work properly. In these individuals, the lining might be too permeable, permitting undigested gluten or bacteria to go through the lining and into the bloodstream, causing inflammation and a bad reaction when gluten-containing foods are consumed. This is called non-celiac gluten sensitivity.
So why do most people “feel better” after eliminating Gluten?
Gluten got its bad reputation by accident. Gluten is not fundamentally problematic for most people. In fact, gluten has been a main staple of our diet for centuries providing us with protein, much-needed fiber, and other nutrients. The culprit is when gluten is in disguise. Wheat is a main component of processed snack foods like chips, crackers, cookies, baked goods, and candy. To turn wheat into these ultra-processed snack foods, it is often stripped down and the end product is highly refined with little resemblance to the actual wheat plant. In addition to stripping down the highly nutritious aspect of the wheat plant, these ingredients are combined with rice flour, fillers, and starches. In other words, unrecognizable, poorly bioavailable, simple sugars. Most people feel better because when they avoid these gluten-containing foods, they eliminate highly processed foods that cause spikes and dips in blood sugar. This is the same reason why people who do not have Celiac disease feel that eliminating gluten gets rid of “brain fog”. While a dose of gluten may cause cognitive impairment in an individual with Celiac or non-celiac gluten sensitivity, the same has not been shown for those who are not gluten intolerant. One long term study of ~14,000 gluten-tolerant women found no significant differences in cognitive test scores between those who consumed high amounts of gluten over 25 years and those who avoided or limited gluten. Restricting dietary gluten to maintain cognitive function in the absence of Celiac disease or established gluten sensitivity is not supported by the data (1).
Where is the proof to show that Gluten is innocent?
While there is a plethora of negative media attention around gluten causing people to question its place in a healthy diet, when we look at the research, the results indicate otherwise. For instance, in a study of >100,000 participants who did not have Celiac disease, researchers found no association between long-term dietary gluten consumption and heart disease risk. More importantly, this study exposed that non-celiac individuals who avoided gluten may have increased their risk of heart disease due to the reduced consumption of whole grains (2). Multiple studies have linked consumption of 2-3 servings of whole grains (remember the base of the food pyramid?) with improved health outcomes such as lower rates of stroke, heart disease, and type II diabetes (3).
As a self-proclaimed “gut afficionado”, it’s important to mention that regular consumption of gluten-containing whole grains and dietary fiber contributes to a greater abundance of gut bacteria. This diversity in healthy gut bacteria may lower the risk of colorectal cancer- a disease that is on the rise in younger adults who consume higher quantities of processed foods (4). This is due to Arabinoxylan oligosaccharide, a prebiotic carbohydrate derived from wheat bran, feeding the healthy bacteria in our gut, subsequently stimulating healthy bacteria in the colon. These healthy bacteria also reduce the risk of inflammatory bowel disease, certain GI cancers, and irritable bowel syndrome (5).
Case Closed: Gluten is no outlaw
Most processed gluten free foods (including baked goods) are not a healthier choice, oftentimes containing more calories and less protein than their gluten-containing counterparts. These foods also tend to be the most processed, containing various binders, gums, and added sugars to make up for the stickiness lost when excluding gluten. If you are not gluten-intolerant, there is no data to support a benefit in following a gluten-free diet. Conversely, some people who consume processed gluten-free foods experience weight gain despite not changing the amount of food intake, likely due to the low nutritional quality of processed gluten-free foods that contain refined sugars, saturated fats, and have a higher glycemic index.
The verdict:
As you strive for your 1% better every day, be sure that you do your homework on the pros and cons of following any diet that eliminates an entire food group. If you must avoid gluten, be mindful that there are plenty of un- or minimally- processed foods that can contribute to the required intake of complex carbohydrates. These include rice, legumes, quinoa, potatoes, popcorn, and other starchy vegetables.
References
Wang Y, Lebwohl B, Mehta R, et al. Long-term Intake of Gluten and Cognitive Function Among US Women. JAMA Netw Open. 2021;4(5):e2113020. doi:10.1001/jamanetworkopen.2021.13020
Lebwohl et al., Long term gluten consumption in adults without celiac disease and risk of coronary heart disease: prospective cohort study. BMJ. 2017 May 2;357:j1892. doi: 10.1136/bmj.j1892.
Bhandari B, Liu Z, Lin S, Macniven R, Akombi-Inyang B, Hall J, Feng X, Schutte AE, Xu X. Long-Term Consumption of 10 Food Groups and Cardiovascular Mortality: A Systematic Review and Dose Response Meta-Analysis of Prospective Cohort Studies. Adv Nutr. 2023 Jan;14(1):55-63. doi: 10.1016/j.advnut.2022.10.010.
Shu L, Huang Y, Si C, Zhu Q, Zheng P, Zhang X. Association between ultra-processed food intake and risk of colorectal cancer: a systematic review and meta-analysis. Front Nutr. 2023 Jul 6;10:1170992. doi: 10.3389/fnut.2023.1170992.
Um CY, Peters BA, Choi HS, Oberstein P, Beggs DB, Usyk M, Wu F, Hayes RB, Gapstur SM, McCullough ML, Ahn J. Grain, Gluten, and Dietary Fiber Intake Influence Gut Microbial Diversity: Data from the Food and Microbiome Longitudinal Investigation. Cancer Res Commun. 2023 Jan 11;3(1):43-53. doi: 10.1158/2767-9764.CRC-22-0154.
About O2X Specialist Maria Urso:
Dr. Maria Urso is an O2X Nutrition Specialist. Dr. Urso is a scientific advocate for optimal health and nutrition. She followed her passion for science and health and obtained her PhD in human physiology from the University of Massachusetts, Amherst. While that degree led her to a career as a scientist, first as an Active Duty soldier in the Army, then in Medical Affairs for industry, she continues to follow her passion for health and nutrition by serving as an advocate and educator.
About O2X Human Performance:
O2X Human Performance provides comprehensive, science-backed programs to hundreds of public safety departments, federal agencies, and the military. O2X works with clients to elevate culture, improve mental and physical wellbeing, support healthy lifestyles, and reduce healthcare costs associated with injuries and illnesses. Driven by results and cutting edge research, O2X programs are designed and delivered by a team of Special Operations veterans, high level athletes, and hundreds of leading experts in their respective fields of human performance.
