THE TRIGGERS FOR IRRITABLE BOWEL SYNDROME VARY FROM PERSON TO PERSON, BUT CERTAIN FOODS ARE MORE LIKELY TO CAUSE PROBLEMS
What is IBS?
Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that affects an estimated 10%–15% of people in the U.S. It can cause a range of digestive symptoms, including:
- Abdominal cramps
- Bloating
- Gas
- Mucus in the stool
- Changes in bowel movements, including frequency and appearance
Some people mainly experience constipation or diarrhea, while others alternate between both. Although IBS can cause significant discomfort, it does not damage the intestines.
The exact cause of IBS remains unclear. Research shows that it affects women about twice as often as men, and most people diagnosed are younger than 45. Having a family history of IBS or certain mental health conditions may also increase the risk.
There is no single test that can definitively diagnose IBS. Healthcare providers may use blood or stool tests and imaging to rule out other conditions. In some cases, a colonoscopy may be recommended to check for abnormalities such as colitis.
IBS symptoms can occur intermittently and may continue for years. Although there is currently no cure, symptoms can often be managed through dietary changes, medications, and other treatments. Food does not cause IBS itself, but certain foods may trigger or worsen symptoms in some people.
Key takeaways
- A low-FODMAP, gluten-free, or high-fiber diet may help manage IBS symptoms, depending on the individual.
- There is no single diet that works for everyone with IBS. Keeping a food diary can help identify foods that trigger symptoms so they can be limited or avoided.
- IBS management may also involve medications, lifestyle adjustments, and complementary approaches such as acupuncture, hypnotherapy, and mindfulness.
The 3 best IBS diets
There is no universal list of foods that everyone with IBS needs to avoid. Food triggers can vary considerably from person to person, and even the same food may cause symptoms at one time but not another.
Dr. Elie Abemayor, Chief of Medicine and Gastroenterology at Northern Westchester Hospital, explains that a food that causes symptoms for one person may have little or no effect on someone else. He also notes that individual tolerance can change over time.
Because of this variability, keeping a food and symptom diary can be useful. Recording what you eat alongside any digestive symptoms may help you recognize personal triggers and determine which foods you may need to reduce or avoid.
1. Low-FODMAP diet
For IBS, one commonly used approach is the low-FODMAP diet. FODMAP refers to a group of carbohydrates—fermentable oligosaccharides, disaccharides, monosaccharides, and polyols—that can be difficult for some people with IBS to absorb. Eating high-FODMAP foods may trigger symptoms such as abdominal cramps, bloating, gas, constipation, or diarrhea.
A low-FODMAP approach typically involves reducing foods containing:
- Fructans and GOS: Found in foods such as wheat, rye, onions, garlic, and legumes
- Lactose: Found primarily in dairy products
- Fructose: Found in foods such as honey and apples, as well as high-fructose corn syrup
- Polyols: Sugar alcohols such as sorbitol, mannitol, xylitol, and maltitol
Importantly, following a low-FODMAP diet does not necessarily mean eliminating every high-FODMAP food permanently. Some foods may be tolerated in smaller portions, and individual responses can differ.
The diet is generally intended to be temporary. After following the initial restriction period for a few weeks, foods containing FODMAPs can gradually be reintroduced to determine which ones trigger symptoms. Once personal triggers are identified, those foods can be limited rather than avoiding every FODMAP-containing food.
Because the process can be complicated, working with a registered dietitian or nutrition professional experienced in the low-FODMAP approach can make it easier to follow the diet appropriately.
2. Gluten-free diet
Another dietary approach that may help some people manage IBS symptoms is a gluten-free diet. Gluten is a protein naturally found in wheat, barley, and rye, so it can be present in foods such as:
- Cereal
- Grains
- Pasta
- Many processed foods
Gluten avoidance is essential for people with celiac disease, but some research also suggests that reducing or eliminating gluten may improve digestive symptoms in certain people with IBS.
3. High-fiber diet
For people with IBS-C, increasing fiber intake may help soften stools, make bowel movements easier, and promote greater regularity.
Fibre also plays an important role in maintaining a healthy gut microbiome. Gastroenterologist Dr. Parastoo Jangouk explains that gut bacteria use fibre to produce short-chain fatty acids, which provide an important source of energy for intestinal cells. A varied diet containing plenty of plant foods and fibre can therefore support overall gut health.
Soluble fibre, found in foods such as beans, fruits, and oats, may be particularly helpful for reducing IBS symptoms. While most Americans consume only around 10–15 grams of fibre per day, the general target is 25–35 grams daily.
If you have IBS and are sensitive to fibre, increase your intake gradually. Starting with just 2–3 additional grams per day may help your digestive system adjust. Increasing fibre too quickly can lead to gas and bloating.
9 IBS foods to avoid
Carbonated drinks: Fizzy beverages can increase gas and bloating, potentially making IBS symptoms more uncomfortable.
Alcohol: Alcohol can speed up intestinal activity, which may make diarrhea worse for people with IBS.
Dairy products: Lactose found in milk and some dairy foods may cause cramping, bloating, gas, diarrhea, or constipation in people who have difficulty digesting it.
Sugary foods: Certain sugars, particularly fructose, may aggravate digestive symptoms in some people with IBS.
Artificial sweeteners: Ingredients such as sorbitol, xylitol, and high-fructose corn syrup can produce digestive effects similar to those caused by certain sugars.
Processed foods: Many processed foods contain combinations of added sugar, fat, and food additives, which may trigger symptoms in some people with IBS.
Caffeine: Caffeinated drinks can stimulate intestinal contractions and may contribute to diarrhea or increased bowel activity.
Certain food additives: Some additives may affect the gut microbiome, potentially contributing to digestive symptoms.
High-fat foods: Foods containing large amounts of fat may affect bowel movement patterns and increase gas or other digestive symptoms in some people with IBS.
Other IBS treatment options
Dietary changes can help manage IBS, but other treatment and lifestyle strategies may also help prevent symptoms and manage flare-ups when they occur.
Medication
Medication may be considered for people with moderate to severe IBS whose symptoms continue despite dietary changes.
- Laxatives: These can help relieve constipation associated with IBS. Common options include magnesium hydroxide and polyethylene glycol.
- Fibre supplements: Products containing psyllium may help add bulk to stool and make bowel movements easier.
- Anticholinergics/antispasmodics: Medications such as dicyclomine and hyoscyamine may help reduce abdominal pain and intestinal cramping, particularly around meals.
- Antidiarrheals: Medications such as loperamide and diphenoxylate/atropine can help control or reduce diarrhea.
- Anti-anxiety medications: These may be considered when anxiety or emotional distress occurs alongside IBS symptoms, as IBS has been associated with anxiety, depression, and other mood conditions.
- Antidepressants: At low doses, certain antidepressants may help reduce the intensity of pain signals between the digestive tract and brain. Tricyclic antidepressants such as amitriptyline, imipramine, and nortriptyline may be prescribed for this purpose.
- Pain medications: Drugs such as pregabalin or gabapentin may be used to help manage IBS-related abdominal pain and bloating.
- IBS-specific prescription medications: Different medications are available depending on the predominant symptoms. Options for diarrhea-predominant IBS include alosetron, rifaximin, and eluxadoline, while constipation-predominant IBS may be treated with medications such as lubiprostone, linaclotide, or plecanatide.
Lifestyle factors that can help IBS
People with mild IBS may be able to control symptoms through lifestyle adjustments, such as staying well hydrated, exercising regularly, and getting sufficient sleep. Counseling may also be helpful, particularly for people experiencing stress or depression, which can sometimes contribute to worsening IBS symptoms.
Complementary health approaches
There is limited evidence supporting complementary or alternative treatments for IBS. However, some studies suggest that certain approaches outside conventional medical care may help reduce symptoms or improve quality of life for some people.
- Acupuncture: Evidence for acupuncture is mixed. Some research has reported symptom improvements among people with IBS, but results have not been consistent.
- Hypnotherapy: Gut-directed hypnotherapy may help improve IBS symptoms, anxiety, depression, disability, and quality of life, although additional research is needed.
- Mindfulness: Mindfulness-based meditation may be useful for some people with IBS, but there is not yet enough evidence to determine how effective it is.
- Yoga: A small study found that yoga may improve abdominal pain, constipation, and nausea, with benefits lasting for at least two months.
- Dietary supplements: Researchers have studied options including Chinese herbal preparations, slippery elm, aloe vera, and probiotics, but evidence for their effectiveness remains limited. Peppermint oil has stronger evidence for helping relieve IBS symptoms.
Because supplements and other complementary treatments can cause side effects or interact with medications, talk with your healthcare provider before adding them to your treatment plan.
Fecal microbiota transplantation (FMT)
Fecal microbiota transplantation (FMT) is an emerging treatment being studied for IBS. The procedure involves transferring processed stool from a healthy donor into the colon of a person with IBS, with the goal of introducing beneficial gut bacteria and restoring the intestinal microbiome.
Researchers are investigating FMT in clinical trials for several digestive conditions, including IBS, Crohn’s disease, and colitis. However, based on the source, its established approved use is for recurrent or severe Clostridium difficile infection, rather than IBS.
Bottom line
IBS can be difficult to manage because its exact cause and diagnostic process remain unclear, and symptoms can differ significantly from one person to another. As a result, treatment often needs to be tailored to the individual. Researchers continue to study the roles of the brain-gut connection, digestive system, and gut microbiome, which may lead to a better understanding of IBS in the future.
Dr. Abemayor also emphasises the importance of recognising that IBS symptoms are genuine and can be associated with physiological differences—not simply something that is “in a person’s head.” Acknowledging and validating those symptoms can itself be an important part of care.
For many people, IBS symptoms can be managed through dietary and lifestyle adjustments, although those with more severe symptoms may require medication. Finding the right approach may involve some trial and error.
However, certain symptoms may indicate that something other than typical IBS needs to be investigated. Contact a healthcare provider if you experience:
- Unexplained weight loss
- IBS symptoms that regularly interfere with sleep
- Rectal bleeding
- Iron-deficiency anemia
- Unexplained vomiting
- Difficulty swallowing
- Abdominal pain that persists after passing gas or having a bowel movement
- New IBS-like symptoms that begin suddenly, particularly after age 50
These warning signs can occur with more serious gastrointestinal conditions, including colon cancer, and should be evaluated by a healthcare professional.
Source: SingleCare