Understanding Your Gut: What Has Gluten but No Fructans?

November 11, 2025 •

4 min read

Recent studies from Monash University suggest that many individuals who report symptoms from 'gluten' are actually reacting to fructans, a different compound found in wheat. This critical distinction raises an important question for people managing digestive issues: what has gluten but no fructans?

Quick Summary

This article explores foods containing gluten but minimal to no fructans, clarifying the difference between gluten and fructan sensitivities. It explains how processing like fermentation can reduce fructans in wheat products like sourdough, providing options for those with fructan intolerance but not celiac disease.

Key Points

Gluten vs. Fructans: Gluten is a protein that triggers celiac disease, while fructans are fermentable carbohydrates (FODMAPs) that can cause IBS symptoms in sensitive individuals.
Fermentation is Key: The long fermentation process in traditional sourdough baking reduces fructan content in wheat and spelt bread, but not the gluten.
Sourdough Bread: A prime example of a food that has gluten but is low in fructans, making it a potential option for those with fructan intolerance but not celiac disease.
Other Examples: Small amounts of soy sauce and some processed foods with wheat derivatives may contain gluten but are low in fructans.
Not All Flour is Equal: Many gluten-free products are not low in fructans and may use high-FODMAP ingredients. Always read the label.
Seek Professional Advice: If you suspect fructan intolerance, consult a dietitian trained in the low-FODMAP diet for a proper diagnosis and management plan.

Gluten vs. Fructans: The Key Difference

Before diving into specific foods, it's essential to understand that gluten and fructans are fundamentally different compounds. Gluten is a protein found in wheat, barley, and rye, responsible for the elasticity and structure of bread dough. In individuals with celiac disease, consuming gluten triggers an autoimmune response that damages the small intestine.

Fructans, on the other hand, are a type of carbohydrate, specifically an oligosaccharide, and are part of the FODMAP family (Fermentable Oligo-, Di-, Mono-saccharides and Polyols). Humans lack the enzyme to properly digest fructans, so they travel to the colon where gut bacteria ferment them. This fermentation process produces gas, which can lead to common irritable bowel syndrome (IBS) symptoms like bloating, gas, and abdominal pain in sensitive individuals. Crucially, fructan intolerance does not cause the intestinal damage associated with celiac disease. This crucial distinction helps explain why a person might react to a wheat bun but not to other high-fructan, gluten-free foods like garlic or onions.

Fermentation: The Secret to Low-Fructan Gluten Foods

For many, the answer to what has gluten but no fructans lies in the power of fermentation. Traditional sourdough baking is a prime example of a process that can significantly reduce fructan content in wheat products. During the long fermentation process, the bacteria and yeast in the sourdough starter consume the fructans in the flour.

This process 'pre-digests' the carbohydrates, making the final bread product much lower in fructans while leaving the gluten protein intact. For people with fructan sensitivity but no celiac disease, this means they can often tolerate spelt or wheat sourdough bread, even though it is not gluten-free.

Other Low-Fructan, Gluten-Containing Foods

Beyond sourdough, some other food products contain gluten but are low in fructans due to processing or naturally lower fructan levels. These are important to note for those on a low-FODMAP diet who do not have celiac disease:

Soy Sauce (in small amounts): In the typical serving size of two tablespoons, soy sauce is considered low-FODMAP, despite containing gluten from fermented wheat. Tamari, a wheat-free alternative, is often completely gluten-free.
Wheat Starch and Malt Extract: In many commercial products, small amounts of wheat derivatives like wheat starch or barley malt are used. While these contain gluten and must be avoided by those with celiac disease, they are often low enough in fructans to be suitable for a low-FODMAP diet.
Certified Oats: Oats themselves are naturally low in fructans but often face cross-contamination with wheat during processing. A person who needs to avoid fructans but not gluten could technically consume regular oats, while someone with celiac disease must opt for a certified gluten-free variety.

It is important to remember that 'gluten-free' does not automatically mean 'low-FODMAP.' Many gluten-free products use high-fructan ingredients like chickpea flour or inulin, so reading labels is always necessary.

Gluten Sensitivity vs. Fructan Intolerance: A Comparison


Feature	Fructan Intolerance (often mistaken for NCGS)	Celiac Disease (Autoimmune Gluten Reaction)
Culprit	Carbohydrate (fructans, a type of FODMAP)	Protein (gluten)
Mechanism	Bacterial fermentation in the colon, causing gas and bloating.	Autoimmune response in the small intestine, causing damage.
Diagnosis	Often involves a low-FODMAP elimination diet and reintroduction.	Blood tests and intestinal biopsy by a physician.
Symptoms	Gastrointestinal issues like bloating, gas, and abdominal pain.	Wide range of symptoms including digestive issues, fatigue, rash, and nutrient malabsorption.
Dietary Solution	Low-FODMAP diet, which can include certain gluten-containing foods.	Lifelong, strictly gluten-free diet.
Key Food Examples	Can tolerate sourdough wheat bread and small amounts of soy sauce.	Must avoid all gluten-containing foods.

Navigating Your Diet: From Confusion to Clarity

If you experience digestive symptoms after eating wheat but have tested negative for celiac disease, you may have fructan intolerance rather than non-celiac gluten sensitivity. Consulting with a registered dietitian, especially one trained in the low-FODMAP diet, can be a beneficial step.

The Path Forward

Work with a Specialist: A dietitian can guide you through a proper elimination and reintroduction process to pinpoint specific triggers.
Trial Low-Fructan, Gluten-Containing Foods: You can experiment with small servings of traditional wheat sourdough or a few tablespoons of soy sauce to see how your body reacts.
Read Labels Carefully: Don't assume 'gluten-free' means 'fructan-free' and check for ingredients like inulin, chicory root, or high-fructan flours.

By understanding the distinction between gluten and fructans, you can make more informed dietary choices. For many, the road to better digestive health may not require a completely gluten-free lifestyle, but rather a more nuanced approach focused on managing fermentable carbohydrates.

Conclusion

While many people who experience digestive distress after eating wheat automatically blame gluten, the real culprit is often fructans. What has gluten but no fructans is the key question for those with IBS or non-celiac wheat sensitivity, and the answer lies in specific food processing techniques and careful portion control. Traditional sourdough bread and certain soy products are excellent examples of foods that offer the taste and texture of gluten without the high fructan load that triggers digestive symptoms in sensitive individuals. Understanding this distinction is crucial for personalized nutrition and expanding dietary options without triggering discomfort.

Learn more about the low-FODMAP diet from the source that developed it at the Monash University Low FODMAP Diet website.

Frequently Asked Questions

Gluten is a protein found in grains like wheat, barley, and rye, which triggers an autoimmune reaction in people with celiac disease. Fructans are fermentable carbohydrates that cause digestive distress like bloating and gas in individuals with fructan intolerance, a common cause of IBS symptoms.

Yes, traditional sourdough bread made with a long fermentation process is often low in fructans, even if made from wheat or spelt. The bacteria and yeast break down the fructans during fermentation, making it easier to digest for those sensitive to them.

Wheat is a major source of both gluten and fructans. Because symptoms like bloating and gas often occur after eating wheat-based foods, people may mistakenly attribute their discomfort to gluten, when fructans are the actual trigger.

While most common wheat products are high in both, certain processed items and small amounts of fermented products like traditional soy sauce can be low in fructans while containing gluten.

No. Celiac disease is a severe autoimmune reaction to gluten itself, not fructans. Anyone with celiac disease must strictly avoid all foods containing gluten, regardless of the fructan content.

No, fermentation does not break down the gluten protein. This is why sourdough bread, despite being low in fructans, still contains gluten and is not safe for people with celiac disease.

The most definitive way is to get tested for celiac disease by a doctor. If tests are negative, a dietitian can guide you through a low-FODMAP elimination diet to determine if fructans are your trigger.