By Aimee Lee Ball
Mintel International recently published a study on gluten-free foods and beverages that highlighted a strong need for product innovation. Although fewer than one percent of Americans have a confirmed diagnosis of celiac disease — an autoimmune reaction to wheat and other grain proteins that damages the small intestine — the gluten-free trend has exploded. Mintel estimated gluten-free product sales at $10.5 billion in 2013 and projected a further 50 percent increase over the next two years. Their message to food makers was clear: keep innovating—there’s profit in gluten-free offerings.
This surge in interest reveals two concurrent facts: relatively few people have a medical reason to avoid gluten, yet many more choose to do so. The gluten-free movement has reached mainstream popularity comparable to popular TV phenomena, with some excesses (you may have even noticed “gluten-free water” marketed in stores).
That raises two questions: Why gluten? And why now?
Two recent popular books offer strong theories. David Perlmutter, M.D., neurologist and author of Grain Brain, argues that wheat harms the brain and calls gluten our generation’s tobacco. Perlmutter links gluten sensitivity to inflammation that can affect the brain and suggests connections between gut inflammation and neurodegenerative diseases. William Davis, M.D., cardiologist and author of Wheat Belly, contends that modern wheat has been altered through breeding to maximize yield and argues it has addictive properties that lead to overeating and various health and mental issues. He characterizes modern wheat as a chronic toxin.
Researchers in the celiac field, however, caution against these sweeping claims. Celiac disease prevalence has increased, roughly doubling every two decades, but the causes are still unclear. One common misconception is that genetically modified wheat is behind the rise. In reality, no genetically modified wheat is commercially available. Stefano Guandalini, M.D., founder of the University of Chicago Celiac Disease Center, notes that genetically engineered wheat intended for the commercial food supply does not exist. In the U.S., any genetically modified crops are tightly regulated by multiple federal agencies under a complex oversight framework.
Jayson Lusk, Ph.D., a food and agriculture economist, points out that genetically modified wheat in the U.S. is limited to research plots and greenhouses and is not released into the food system. Economic and trade factors also discourage commercialization: major importers like Europe and Japan have been wary of genetically engineered crops, and wheat farmers often prefer to save seed from year to year rather than buy new, modified seed.
Wheat’s genetics are inherently complex and difficult to alter. Brett F. Carver, Ph.D., a wheat breeding and genetics professor, explains that a wheat plant may express hundreds of thousands of genes during growth, and most of the kernel is starch. Because gluten is a protein, it is challenging to breed wheat that both increases yield and substantially alters protein content. Current gluten levels in wheat remain similar to historical ranges; early 20th-century wheat protein measured between 14 and 18 percent, while today it is roughly 13 to 16 percent.
Some foods do have added gluten to change texture—making bagels chewier, for instance—and many processed products, including meat substitutes like seitan, rely on concentrated wheat protein. Still, overall wheat consumption per capita has declined: it was around 240 pounds per person in the early 1900s and is now closer to 120–130 pounds.
A major turning point in public awareness came in 2003 with a study led by Alessio Fasano, M.D., showing that about one in 133 Americans had celiac disease. Improved screening tests, notably the tTG blood test, are more sensitive and affordable than older methods, making diagnosis more practical. But a definitive celiac diagnosis still requires an intestinal biopsy and genetic testing for associated genes.
Fasano, now director of the Center for Celiac Research at Massachusetts General Hospital for Children, warns against conflating scientific evidence with hyperbole. While gluten is a protein humans digest imperfectly and may trigger immune responses in susceptible people, Fasano rejects the notion that everyone should avoid gluten. He describes the issue as one of tolerance: most people’s immune systems handle gluten without developing disease.
Researchers propose several theories for the apparent increase in celiac disease and related sensitivities. One prominent idea involves the microbiome — the community of microbes that live in and on our bodies. Changes associated with modern life, such as widespread antibiotic use and rising cesarean delivery rates, have altered early microbial exposures and may influence immune development. Stefano Guandalini compares a healthy microbiome to a skilled conductor leading a balanced orchestra; disruptions can throw immune responses out of harmony.
Some studies have explored non-celiac gluten sensitivity (NCGS), a condition in which people report symptoms after consuming gluten despite lacking celiac biomarkers. Early research suggested gluten might cause symptoms in non-celiac individuals, but later, more controlled trials raised doubts. Attention shifted to FODMAPs — fermentable sugars found in foods like apples, onions, garlic, and wheat — which can cause bloating, gas, diarrhea, and fatigue when poorly absorbed. Eliminating bread and other wheat products can reduce FODMAP intake and thereby relieve symptoms, creating the impression that gluten was the culprit. The FODMAP concept has gained traction in some places, including certification for low-FODMAP products.
Guandalini emphasizes that celiac disease can be diagnosed objectively through biomarkers, while NCGS lacks specific lab tests and often depends on patient-reported symptoms. He also notes emerging animal research on wheat proteins such as amylase-trypsin inhibitors (ATIs), which might provoke inflammation, but evidence in humans remains inconclusive.
Critics who blame modern hybridization for rising celiac rates point to decades of selective breeding that altered wheat gradually. Norman Borlaug’s high-yield, disease-resistant wheat varieties played a key role in addressing global hunger, and wheat has evolved over millennia rather than in a few decades. Fasano and others argue that hybridization alone cannot explain the recent rise; rather, changing environmental exposures and microbiome composition likely play major roles in loss of tolerance to gluten.
This uncertainty is frustrating for both researchers and patients. Amy Burkhart, M.D., R.D., who specializes in digestive health and has multiple family members with celiac disease, says the popularity of gluten-free diets can complicate the lives of people who need strict medical management. Conflicting information online adds to the confusion.
There is reason for cautious optimism, however. Guandalini says researchers are close to developing therapies aimed at restoring gluten tolerance by modulating the immune response. While a definitive cure is not yet available, ongoing research offers hope that more targeted treatments will emerge.
In the meantime, separating evidence from hype remains a challenge for consumers and clinicians alike — a reminder that distinguishing reliable information from noise is as important as ever.
Photo credit: Maren Caruso