The biology behind the problem is unforgiving. In genetically susceptible individuals carrying the HLA-DQ2 or HLA-DQ8 variants, dietary gluten triggers an adaptive immune cascade in which the enzyme tissue transglutaminase-2 chemically modifies gliadin peptides, provoking T-cell-driven destruction of the small intestinal lining. The result is villous atrophy and crypt hyperplasia, which shrink the absorptive surface of the gut and compromise the epithelial barrier. Diagnosis still requires positive serology, typically tissue transglutaminase IgA antibodies, together with a small-intestinal biopsy demonstrating villous damage, yet many people who self-diagnose or drift onto gluten-free diets have never been formally tested. Survey data suggest a global prevalence of about 1.4 percent, but an iceberg effect means most cases remain undiagnosed, and athlete-specific figures are almost nonexistent.

The numbers that do exist are telling. In a survey of 141 NCAA collegiate athletes, roughly 2.8 percent reported a physician diagnosis of celiac disease, while about 11.3 percent scored above the threshold for celiac-consistent symptoms, yielding odds of high-symptom status nearly 18 times higher than a general-population benchmark. The authors of the review caution that these figures rely on self-report, were drawn from a small convenience sample skewed toward white Midwestern athletes, and were compared against general-population rather than age-matched non-athlete controls. Still, the signal is hard to ignore, particularly because intense endurance exercise independently raises intestinal permeability, elevates serum zonulin, and upregulates the pore-forming tight junction protein claudin-2, mechanisms that converge with celiac pathology and could amplify risk or mask symptoms in genetically susceptible athletes through what researchers call Exercise-Induced Gastrointestinal Syndrome.

Even after diagnosis, the challenges multiply. The gold-standard treatment, a strict gluten-free diet, is nutritionally treacherous for people whose energy demands can reach 50 to 80 kilocalories per kilogram of body weight per day in endurance sports. Gluten-free products are frequently made from refined rice, tapioca, and potato starches, carry a higher glycemic index than wheat equivalents, and lack the iron and calcium fortification of conventional foods. Cross-contamination is a persistent hazard: studies of restaurant meals labeled gluten-free have found that roughly a third contain detectable gluten, and sensitive patients can suffer mucosal injury at daily exposures as low as 10 milligrams. The socioeconomic burden compounds the problem, with gluten-free foods costing 76 to 518 percent more than conventional equivalents in the United Kingdom, roughly double in Saudi Arabia, and up to 259 percent more on average in the United Arab Emirates, a burden that falls hardest on young, underfunded athletes who report food-related anxiety, social isolation, and meals skipped before competition.

The nutritional consequences are measurable and severe. Iron deficiency anemia affects up to 82 percent of celiac patients, and only about half restore their iron stores within a year of starting the gluten-free diet. Exercise compounds the deficit because the hormone hepcidin, which blocks iron absorption, remains elevated for up to six hours after training, cutting fractional iron absorption by more than a third. The review recommends timing iron-rich meals and supplements to the early morning, avoiding the three-to-six-hour post-exercise window, and pairing plant-based iron sources with vitamin C. Vitamin D deficiency, present in 8 to 88 percent of celiac patients, carries a staggering 23.3-fold higher risk of fifth metatarsal stress fractures at low serum levels, prompting suggested intakes of 2,000 to 6,000 IU per day for affected athletes. Calcium, magnesium, zinc, and B vitamins follow similar patterns of depletion driven jointly by malabsorption and the poor nutrient density of gluten-free substitutes.

The review also ventures into emerging territory. Sucrosomial iron formulations are preferred for athletes who cannot tolerate ferrous sulfate, and magnesium citrate or glycinate outperform oxide, whose bioavailability is a mere 4 percent. Genetic polymorphisms in the vitamin D-binding protein and receptor genes may explain why some athletes need substantially larger doses to reach the same serum 25-hydroxyvitamin D target of 30 to 50 nanograms per milliliter. On the supplement front, multi-strain probiotics containing Bifidobacterium breve and Lactobacillus plantarum reduced gastrointestinal symptoms 29 percent more than placebo in meta-analysis, while the alanyl-glutamine dipeptide, which survives gastric digestion and upregulates the tight junction proteins claudin and occludin, shows theoretical promise for a gut battered both by disease and by exercise-induced ischemia, though no trial has yet tested it in celiac athletes.

Perhaps the most underappreciated dimension is psychological. A meta-analysis found that people with celiac disease face roughly six-fold higher odds of anxiety and more than double the odds of depression, and collegiate athletes with more celiac-consistent symptoms reported poorer quality of life across physical, psychological, social, and environmental domains, along with greater depression and perceived stress. Childhood celiac disease carries a 19 percent increased risk of psychiatric disorder that persists into adulthood. Disordered eating is another red flag, with a pooled prevalence of nearly 9 percent and a significantly elevated risk of anorexia nervosa, a dangerous overlap in athletic populations where restrictive eating is already common. Even cognition is affected: neuroimaging studies have documented slower reaction times and white matter microstructural changes, the so-called brain fog, with direct implications for tactical decision-making and reaction-time precision in sport.

To bring order to this fragmented picture, the authors lay out a monitoring architecture that spans serology, biochemistry, and performance. Tissue transglutaminase IgA with total IgA remains the first-line screen, and clinicians are urged to test athletes presenting with unexplained fatigue, recurrent infections, refractory iron deficiency, or disproportionate stress fractures, noting that classic gastrointestinal symptoms may be absent in up to half of atypical cases. HLA-DQ2/DQ8 genotyping, with a negative predictive value above 99 percent when both alleles are absent, helps when athletes have already gone gluten-free. Blood sampling should be standardized, ideally in the morning after at least 48 hours of rest, to control for exercise-induced analytical variation, a detail routinely neglected in clinical practice. Dual-energy X-ray absorptiometry tracks bone mineral density and distinguishes genuine fat-free mass recovery from the fat gain and sarcopenic pattern that has been observed after a year on a gluten-free diet, while countermovement jump, handgrip strength, VO2 max, heart rate variability, and patient-reported symptom and quality-of-life scales complete the functional picture.

The review is candid about its limits. It is a structured narrative review conducted under the SANRA quality framework, not a systematic review with risk-of-bias assessment or meta-analysis, and much of its practical guidance extrapolates from the general celiac population, athletic populations without the disease, and mechanistic studies rather than from trials in biopsy-confirmed celiac athletes, of which there are almost none. Its recommendations should therefore be read as hypothesis-generating and practice-oriented rather than graded clinical guidelines. Still, the authors argue that no existing review has previously woven nutritional assessment, supplementation, and performance monitoring into a single athlete-centered framework, and they call for randomized controlled trials with biopsy-confirmed enrollment, adherence-verified comparator arms, and stratification by sport type, sex, age, and mucosal healing status.

The broader message resonates beyond the locker room. Celiac disease sits at the intersection of immunology, gastroenterology, exercise physiology, and psychology, and athletes amplify every one of those variables. If future research confirms that the physiological stress of training lowers the threshold for disease expression in genetically susceptible individuals, sports medicine will need athlete-specific epidemiology, screening checklists, and possibly an international registry to track adherence, biomarkers, and performance over time. For now, the review offers coaches, dietitians, and team physicians a practical warning: when an athlete’s engine keeps misfiring for reasons that training loads and talent cannot explain, it may be worth checking whether the fuel line itself is under attack.

Subject of Research: Integrated nutritional and performance monitoring for athletes with celiac disease

Article Title: An Integrated Nutritional and Performance Monitoring Framework for Athletes with Celiac Disease: A Structured Narrative Review

Article References: Yamani, O. B., Alghamdi, M. M., Zagzoog, A. M., Noorwali, E. A., Alotaibi, R. A., Alghannam, A. F., Aljaloud, K. S., Aragon, A. A., & Elsahoryi, N. A. (2026). An Integrated Nutritional and Performance Monitoring Framework for Athletes with Celiac Disease: A Structured Narrative Review. Current Research in Food Science, Article 101568. https://doi.org/10.1016/j.crfs.2026.101568

Image Credits: AI Generated

DOI: Not provided

Keywords: celiac disease, athletes, sports nutrition, gluten-free diet, iron deficiency, vitamin D, intestinal permeability, micronutrients, performance monitoring, probiotics, glutamine, athlete health