The Low FODMAP Diet for IBS, SIBO, and Chronic Digestive Symptoms

A functional-medicine approach to reducing bloating, gas, abdominal pain, and bowel irregularity

Diagram of the large intestine showing IBS symptoms, abnormal bowel contractions, and digestive mechanisms affected by high FODMAP foods

Bloating after meals. Abdominal pain that comes and goes. Alternating constipation and diarrhea.
If these symptoms sound familiar, you’re not alone—and they’re often not “just stress” or something you have to live with.

The low FODMAP diet is a clinically validated elimination diet designed to reduce digestive symptoms by addressing how certain carbohydrates interact with the gut microbiome and intestinal motility. When applied correctly—and personalized—it can be a powerful short-term therapeutic tool for people with IBS, SIBO, and other functional gut disorders.

What Is the Low FODMAP Diet

Understanding fermentable carbohydrates and digestive stress

FODMAP is an acronym for specific types of carbohydrates that are poorly absorbed in the small intestine:

  • Fermentable

  • Oligosaccharides

  • Disaccharides

  • Monosaccharides

  • Polyols

These carbohydrates are bonded sugar molecules. Because the small intestine primarily absorbs single sugar units, FODMAPs pass into the large intestine, where they draw in water and are fermented by gut bacteria. This fermentation produces gas and short-chain fatty acids, leading to bloating, abdominal distention, and pain in susceptible individuals (1).

This process does not cause symptoms in everyone. However, in people with altered gut motility, dysbiosis, visceral hypersensitivity, or bacterial overgrowth, it can significantly worsen digestive discomfort.

Gut Health & Dysbiosis: Understanding Imbalances Like SIBO, Candida, and IBS

Persistent food reactions often reflect deeper microbiome disruption that requires targeted testing and treatment beyond dietary restriction.

Who May Benefit From a Low FODMAP Diet

Symptoms that suggest carbohydrate intolerance

A low FODMAP approach may be appropriate if you experience:

  • Chronic bloating or excessive gas

  • Abdominal pain or cramping

  • Diarrhea, constipation, or alternating stool patterns

  • Visible abdominal distention

These symptoms are commonly seen in conditions such as:

  • Irritable bowel syndrome (IBS)

  • Small intestinal bacterial overgrowth (SIBO)

  • Celiac disease with persistent IBS-like symptoms

  • Inflammatory bowel disease (IBD)

  • Leaky gut and post-infectious gut dysfunction

In IBS and SIBO, digestion often slows, allowing fermentable carbohydrates to remain in the gut longer. This creates an optimal environment for bacterial fermentation and symptom flares (2)(3).

Leaky Gut Syndrome – How to Restore Your Health From the Inside Out

Food reactions often intensify when the intestinal barrier is compromised, making gut repair as important as dietary modification.

The Low FODMAP Diet for IBS and IBD

What the research shows

The strongest evidence for the low FODMAP diet exists in IBS. Multiple studies demonstrate significant reductions in bloating, abdominal pain, and overall symptom severity when high-FODMAP foods are reduced (4)(5).

Because of this success, researchers have explored the low FODMAP diet in IBD. Current evidence suggests that while the diet does not reduce intestinal inflammation, it may improve functional symptoms such as gas, bloating, abdominal pain, and fatigue (6).

In one analysis of nine studies involving IBD patients, symptom improvement was observed in these areas, though inflammatory markers and disease activity remained unchanged (7). A small pediatric study also demonstrated symptom reduction in most children following a low FODMAP intervention (8).

Because this research is still emerging, professional guidance is essential before applying this diet in IBD.

The Low FODMAP Diet and Celiac Disease

When gluten-free is not enough

People with celiac disease must remove gluten from their diet completely. However, some continue to experience persistent IBS-like symptoms even with strict adherence.

A review of studies examining low FODMAP interventions in celiac patients showed improvements in digestive symptoms, quality of life, and overall well-being (9). While these findings are promising, they also highlight the importance of avoiding unnecessary long-term restriction.

High and Low FODMAP Foods

What to limit—and what to eat instead

Many nutrient-dense, whole foods naturally contain FODMAPs. Common high-FODMAP categories include fruit, dairy, cereals, and legumes.

Higher FODMAP foods commonly associated with symptoms

  • Alcohol and high-caffeine beverages

  • Cashews and pistachios

  • Watermelon, apricots, cherries, and other stone fruits

  • High-fructose corn syrup and certain sweeteners

  • Onions, artichokes, beets, and some cruciferous vegetables

  • Regular milk, yogurt, ice cream, and some soft cheeses

  • Wheat and rye products

Lower FODMAP alternatives

  • Pineapple, kiwi, oranges

  • Maple syrup and small amounts of dark chocolate

  • Carrots, potatoes, eggplant

  • Lactose-free dairy, almond milk, brie, and most hard cheeses

  • Oats, quinoa, rice, gluten-free breads

  • Eggs, tofu, and minimally processed meats and seafood

Important:
The goal is not permanent avoidance. Most people tolerate many high-FODMAP foods once underlying gut dysfunction is addressed.

Why the Low FODMAP Diet Is Not a Long-Term Diet

Protecting nutrient status and the microbiome

Strict long-term FODMAP restriction can lead to nutrient deficiencies and reduced gut microbiome diversity (10). Studies consistently show better outcomes when the diet is guided by a trained healthcare professional, particularly during reintroduction (11).

Advanced Functional Lab Testing
Gut Health & Digestive Restoration

The Three Phases of the Low FODMAP Diet

A structured path to personalization

  • Elimination

    Lasting two to six weeks, this phase removes high-FODMAP foods to reduce fermentation and calm symptoms

  • Reintroduction

    Over six to eight weeks, foods are added back one at a time to identify personal triggers. Proper timing and symptom tracking are critical (12).

  • Maintenance

    This long-term phase focuses on the least restrictive diet possible while maintaining symptom control.

Is the Low FODMAP Diet Right for You

Why functional medicine guidance matters

Digestive symptoms are rarely caused by food alone. They are often influenced by:

  • Gut motility

  • Microbiome balance

  • Inflammation

  • Nervous system regulation

  • Hormonal and metabolic factors

A functional medicine approach helps determine whether FODMAP sensitivity is the driver—or simply a signal of deeper imbalance.

Functional & Integrative Medicine
Chronic Illness & Complex Case Care

You may request a complimentary 15-minute consultation with Dr. Martina Sturm to identify the root causes of your digestive symptoms and develop a sustainable, gut-healing plan.

Frequently Asked Questions About the Low FODMAP Diet

What is the low FODMAP diet and how does it work

The low FODMAP diet is a structured elimination diet designed to reduce fermentable carbohydrates that are poorly absorbed in the small intestine. These carbohydrates can trigger bloating, gas, and abdominal pain in people with IBS, SIBO, and other digestive disorders. By temporarily removing high FODMAP foods and then reintroducing them systematically, individuals can identify personal food triggers and reduce symptoms.

What conditions benefit most from the low FODMAP diet

The low FODMAP diet is most commonly used for irritable bowel syndrome and small intestinal bacterial overgrowth, but it may also help people with inflammatory bowel disease, celiac disease with persistent IBS-like symptoms, and leaky gut. It can be especially helpful for chronic bloating, gas, constipation, diarrhea, or alternating bowel patterns.

How long should I follow the low FODMAP diet

The elimination phase typically lasts two to six weeks. High FODMAP foods are then reintroduced gradually over six to eight weeks to identify which foods provoke symptoms. The diet is not intended to be followed long term, as prolonged restriction can increase the risk of nutrient deficiencies and negatively impact the gut microbiome.

What are the three phases of the low FODMAP diet

The diet is implemented in three phases. The elimination phase removes high FODMAP foods to calm symptoms. The reintroduction phase adds foods back one at a time to identify sensitivities. The maintenance phase focuses on a personalized, sustainable eating plan that avoids known triggers while supporting overall nutrition.

What are common high FODMAP foods to avoid

Common high FODMAP foods include onions, garlic, wheat, rye, regular dairy products, certain legumes, stone fruits such as cherries and peaches, and artificial sweeteners like high-fructose corn syrup.

What are safe low FODMAP foods

Low FODMAP foods often include pineapple, kiwi, potatoes, carrots, quinoa, oats, lactose-free dairy, eggs, tofu, and most unprocessed meats and seafood. Individual tolerance can vary, which is why reintroduction is an essential step.

Is the low FODMAP diet safe for children

The low FODMAP diet can be used in children, but only under the supervision of a qualified healthcare provider or dietitian. While studies suggest it may help children with IBD and other digestive conditions, professional guidance is necessary to prevent nutrient deficiencies and ensure proper growth.

Can I follow the low FODMAP diet on my own

Research shows that people who follow the low FODMAP diet with professional guidance have better symptom improvement and fewer nutritional risks. Working with a functional medicine practitioner or dietitian helps ensure the diet is applied correctly and personalized effectively.

How is the low FODMAP diet different from a gluten-free diet

A gluten-free diet eliminates gluten-containing grains such as wheat, barley, and rye. The low FODMAP diet is broader and focuses on fermentable carbohydrates, including some foods that may be gluten-free but still trigger digestive symptoms.

What are the risks of following the low FODMAP diet long term

Strict long-term avoidance of FODMAP foods can lead to vitamin and mineral deficiencies and reduced gut microbiome diversity. This is why the diet should be used as a short-term therapeutic tool, followed by careful reintroduction and personalization.


Resources

  1. Gastroenterology – Nonceliac Gluten Sensitivity

  2. Gut – Intestinal cell damage and systemic immune activation in individuals reporting sensitivity to wheat in the absence of coeliac disease

  3. BMC Gastroenterology – An updated overview of spectrum of gluten-related disorders: clinical and diagnostic aspects

  4. Gastroenterology – Efficacy of the low FODMAP diet in adults with irritable bowel syndrome

  5. Alimentary Pharmacology & Therapeutics – A diet low in FODMAPs reduces symptoms of irritable bowel syndrome

  6. Journal of Gastroenterology and Hepatology – FODMAPs and functional gastrointestinal symptoms

  7. Nutrients – Low FODMAP diet in inflammatory bowel disease: systematic review

  8. Journal of Pediatric Gastroenterology and Nutrition – Low FODMAP diet in children with inflammatory bowel disease

  9. Clinical Gastroenterology and Hepatology – Low FODMAP diet for persistent symptoms in treated celiac disease

  10. Nutrients – Nutritional adequacy and long-term effects of the low FODMAP diet

  11. Journal of Human Nutrition and Dietetics – Dietitian-led low FODMAP diet outcomes

  12. Gastroenterology – Reintroduction phase accuracy in low FODMAP dietary intervention