Why do Athletes Avoid Gluten? Separating Fact from Trend

November 9, 2025 •

5 min read

A 2015 study found that over 40% of high-level athletes reported following a gluten-free diet, a rate four times higher than in the general population. This statistic reveals a significant disparity between clinical needs and dietary practice in sports, prompting a closer look at why athletes avoid gluten, despite limited scientific evidence of performance gains for those without a medical condition.

Quick Summary

Athletes may avoid gluten for medically diagnosed issues like celiac disease, to alleviate gastrointestinal discomfort, or due to a belief in performance enhancement. For non-sensitive individuals, scientific evidence does not support performance benefits, and the risks of nutritional deficiencies are a concern.

Key Points

Medical Necessity: For athletes with diagnosed celiac disease, a gluten-free diet is not a choice but a critical medical requirement to prevent intestinal damage and improve overall health and performance.
Perceived Benefits: Many non-celiac athletes report feeling better and performing better on a gluten-free diet, but scientific research has not consistently shown a significant performance benefit for those without a medical sensitivity.
The Placebo Effect: The psychological belief that a gluten-free diet is improving performance can lead to perceived gains. If an athlete believes it works, the powerful placebo effect can influence their perceived well-being and performance.
GI Distress: Gastrointestinal issues common in endurance sports are often misattributed to gluten. Other factors, such as high-FODMAP foods, intense training, or inadequate carbohydrate intake, can be the actual cause of digestive symptoms.
Nutritional Risks: Without proper guidance, eliminating gluten can lead to nutritional deficiencies in fiber, B-vitamins, and iron, as many gluten-containing grains are fortified with these nutrients. This can negatively impact performance and overall health.
Consult a Professional: It is highly recommended that athletes consult a doctor and registered dietitian before starting a gluten-free diet to receive a proper diagnosis, avoid self-diagnosis, and ensure a balanced nutritional plan.

The Medical Rationale: Celiac Disease and Non-Celiac Gluten Sensitivity

For a small subset of the population, including some athletes, avoiding gluten is a medical necessity rather than a dietary choice. Understanding the difference between a serious medical condition and a less-understood sensitivity is crucial.

Celiac Disease: A Medical Necessity

Approximately 1% of the global population has celiac disease, an autoimmune disorder where gluten ingestion triggers an immune response that damages the lining of the small intestine. This damage impairs nutrient absorption and can lead to severe health issues, including fatigue, anemia, and bone pain, all of which directly hinder athletic performance. For these athletes, a strictly gluten-free diet is the only effective treatment, leading to a significant improvement in health and athletic potential. This is not a trend but a critical medical intervention.

Non-Celiac Gluten Sensitivity (NCGS)

NCGS is a condition where individuals experience similar gastrointestinal symptoms—such as bloating, gas, and abdominal pain—after consuming gluten, but without the intestinal damage or autoimmune response of celiac disease. While a formal diagnosis is difficult, some athletes with NCGS report a reduction in symptoms and an overall feeling of improved wellness when they eliminate gluten. The perceived reduction in discomfort and inflammation can lead to better training and performance, even if the direct ergogenic effect is not scientifically proven. It is important to note, however, that other components of wheat, such as FODMAPs (Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols), may be the actual cause of symptoms.

Perceived Performance and Anecdotal Evidence

Beyond medical necessity, a large number of non-celiac athletes have adopted a gluten-free diet based on the perception that it offers a competitive edge. This is largely fueled by anecdotal stories from high-profile athletes and unsubstantiated commercial claims.

The Placebo Effect in Athletic Performance

For athletes without a diagnosed sensitivity, any perceived performance enhancement might be due to the powerful placebo effect. If an athlete firmly believes that a dietary change is benefiting them, this psychological conviction alone can influence their performance. In one study, athletes felt that their performance was impaired while consuming gluten, and improved after its exclusion, despite no actual measured difference in performance metrics. This highlights the complex role of belief in influencing athletic outcomes.

Case Study: High-Profile Athletes

The trend has been notably popularized by figures like tennis star Novak Djokovic, who credits his mid-career resurgence to a gluten-free diet after being diagnosed with a sensitivity. Other prominent athletes, including Olympic swimmer Dana Vollmer, have also gone gluten-free due to medical issues and reported significant health improvements. These individual success stories, while powerful, often get generalized and applied to all athletes, regardless of their own health profile, driving the widespread adoption of the diet.

Addressing Gastrointestinal Distress

For many athletes, the push toward a gluten-free diet comes from experiencing gastrointestinal distress during or after intense exercise. While gluten can be a culprit for some, it's not the only factor.

Endurance Athletes and Gut Issues

Prolonged endurance exercise can cause gastrointestinal distress in a high percentage of athletes due to factors like reduced blood flow to the gut and the use of high-carbohydrate sports drinks. This can lead athletes to wrongly attribute symptoms like bloating and discomfort to gluten. A detailed evaluation with a professional is needed to pinpoint the real cause.

Beyond Gluten: The Role of FODMAPs

Many gluten-containing foods are also high in fermentable carbohydrates known as FODMAPs. Research shows that reducing FODMAP intake can significantly reduce gastrointestinal symptoms in athletes, including those who believe they have a gluten sensitivity. A low-FODMAP diet might be a more targeted and effective approach for managing GI issues, rather than needlessly eliminating all gluten.

The Risks of an Unsupervised Gluten-Free Diet

Adopting a gluten-free diet without proper medical or nutritional guidance can pose several risks that may negatively impact performance and health.

Potential Nutritional Deficiencies

Gluten-containing grains like wheat are often fortified with essential nutrients, including B-vitamins, iron, and fiber. When these are eliminated and not properly replaced with other whole-food sources, athletes risk developing nutritional deficiencies that can compromise performance and lead to health issues. Examples of naturally gluten-free, nutrient-dense alternatives include:

Carbohydrates: Quinoa, brown rice, potatoes, sweet potatoes, and legumes
Fiber: Fruits, vegetables, nuts, and seeds
Protein: Lean meats, eggs, dairy, and plant-based proteins like lentils and tofu

Financial and Social Considerations

Gluten-free products can be more expensive than their traditional counterparts, potentially adding a financial burden. Furthermore, relying on heavily processed gluten-free substitutes can still lead to a diet high in sugar and unhealthy fats. A truly healthy gluten-free diet should focus on whole, unprocessed foods.

Scientific Consensus vs. Athletic Perception


Reason Athletes Avoid Gluten	Scientific Evidence for Non-Celiac Athletes	Conclusion
Celiac disease	Gluten triggers an autoimmune response, causing intestinal damage.	Essential for health; improves performance by preventing malabsorption and systemic symptoms.
Non-celiac gluten sensitivity	Reported symptoms like bloating and fatigue in response to gluten.	May improve well-being for sensitive individuals, though evidence is variable and other factors like FODMAPs may be involved.
Reduced inflammation	No significant reduction in inflammation markers observed in studies on non-celiac athletes.	Perceived benefit, not supported by current scientific evidence for non-sensitive individuals.
Perceived performance enhancement	Blinded studies show no significant performance differences between gluten and non-gluten diets.	Likely a placebo effect, a psychological belief influencing perceived outcomes.
Reduced gastrointestinal issues	Symptoms often triggered by exercise intensity or other dietary factors like FODMAPs, not just gluten.	Targeted elimination of FODMAPs under a dietitian's guidance may be a better strategy.

Conclusion: Making an Informed Decision

In summary, while there are valid medical reasons why athletes avoid gluten, such as celiac disease and genuine sensitivity, the notion that a gluten-free diet universally enhances athletic performance is not supported by scientific evidence. The widespread trend is largely driven by a combination of anecdotal successes, a strong placebo effect, and a misattribution of gastrointestinal distress to gluten. Athletes considering a gluten-free diet should prioritize proper medical testing and consultation with a registered dietitian to ensure their dietary choices are based on solid evidence and meet all nutritional needs. By focusing on a whole-food, nutrient-dense diet, athletes can avoid the risks of unsupervised dietary restriction and optimize their health and performance effectively.

For more in-depth scientific perspectives on gluten and athletic performance, consult academic resources like the one available via the National Institutes of Health.

Frequently Asked Questions

For athletes without a diagnosed gluten sensitivity or celiac disease, there is no strong scientific evidence to support that a gluten-free diet provides a performance advantage. Any perceived benefits may be psychological.

Celiac disease is an autoimmune disorder that causes damage to the small intestine upon gluten ingestion. Non-celiac gluten sensitivity (NCGS) causes similar symptoms but does not involve the same intestinal damage or autoimmune response.

FODMAPs are fermentable carbohydrates that can cause GI distress. Some high-FODMAP foods also contain gluten. Eliminating gluten might coincidentally reduce FODMAP intake, alleviating symptoms that were not actually caused by gluten.

An improperly planned gluten-free diet can lead to deficiencies in essential nutrients like fiber, B vitamins, and iron, potentially compromising athletic performance and overall health.

By focusing on naturally gluten-free whole foods such as fruits, vegetables, lean proteins, nuts, seeds, and alternative grains like quinoa and brown rice, athletes can maintain a nutrient-dense and balanced diet.

The popularity is often driven by perceived health benefits, anecdotal stories from fellow athletes, and the powerful placebo effect, rather than concrete scientific evidence for non-sensitive individuals.

Yes, it is highly recommended to seek medical testing and consult a registered dietitian before eliminating gluten. Self-diagnosing can hide other underlying medical issues and lead to inadequate nutrition.