Which Foods Trigger IBS?

Some people with irritable bowel syndrome (IBS) have specific triggers foods that can cause or worsen their symptoms.

Irritable bowel syndrome (IBS) is a condition that describes a group of gastrointestinal symptoms including abdominal pain, bowel habit changes, excess gas, bloating (abdominal distention), abdominal cramping, and food intolerances. 

Irritable bowel syndrome is considered a "functional" disorder because changes in the functioning of the digestive system cause the collection of symptoms referred to as IBS. IBS is a problem with the movement (motility) of the digestive tract rather than a result of damage to the tissues of the digestive system. 

There are three different types of IBS: 

• IBS with constipation (IBS-C)
• IBS with diarrhea (IBS-D)
• IBS with mixed bowel habits (IBS-M)

IBS is not the same as colitis or Crohn’s disease, which is a group of separate conditions referred to as inflammatory bowel disease (IBD).

Symptoms of irritable bowel syndrome (IBS) include: 

• Abdominal pain, often related to bowel movements
• Changes in bowel movements, which may be diarrhea, constipation, or both, depending on the type of IBS 
• Bloating
• Feeling as if a bowel movement is incomplete
• Whitish mucus in the stool

Women with IBS frequently have more symptoms during their periods.

The cause of irritable bowel syndrome (IBS) is unknown but it is believed to be related to problems with brain-gut interaction, that is, how the brain and gut work together.

Different factors may play a role in causing IBS, including: 

• Genetics
• Bacterial infections in the digestive tract
• Small intestinal bacterial overgrowth (SIBO)
• Food intolerances or sensitivities
• Stressful or difficult early life events, such as physical or sexual abuse 
• Mental disorders such as depression, anxiety, and somatic symptom disorder

Some people with irritable bowel syndrome (IBS) have specific trigger foods that can cause or worsen their symptoms. 

• Certain carbohydrates referred to as FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) cause symptoms in some people with IBS.
  • FODMAPs are found in products such as:
    • Some grains (what, rye)
    • Certain fruits (pears, apples, apples, apricots, blackberries, cherries, mango, nectarines, plums, and watermelon, or juice containing these fruits)
    • Certain vegetables (artichokes, onions, garlic and garlic salts, asparagus, beans, cabbage, cauliflower, lentils, mushrooms, and sugar snap or snow peas)
    • Products with artificial sweeteners including candy and gum, with sweeteners ending in “–ol,” such as sorbitol, mannitol, xylitol, and maltitol
    • Dairy products (also cause lactose intolerance)
    • Honey and foods with high-fructose corn syrup
  • Some people may to be sensitive to only some FODMAPs. 
  • A diet high in FODMAPs may result in bloating, gas, and diarrhea in some people with IBS
• Other foods that may cause or worsen diarrhea symptoms include:
  • Bacon and other processed meats
  • Broccoli and spinach
  • Corn
  • Raw vegetables and raw fruits
  • Beans
  • Chocolate
  • Beer
  • Fatty foods
  • Spicy foods
  • Licorice
  • Nuts
  • Red wine
  • Shellfish
  • Whole grains
• Foods that dehydrate may worsen the constipation symptoms
  • Alcohol
  • Caffeine
• Fiber products can help IBS (in case of constipation) or worsen IBS (diarrhea)
• Some patients may be advised to avoid gluten, a protein found in wheat, barley, and rye, among other grains 

Doctors may recommend IBS patients keep a food diary to note when symptoms occur. If certain foods aggravate symptoms, avoid those foods. 

Irritable bowel syndrome (IBS) is diagnosed first with a patient history and a physical exam. Other tests that may be used to diagnose IBS or rule out other conditions include: 

• Blood tests to check for anemia, infection, and digestive diseases
• Stool tests to check for blood in the stool or other signs of infections or diseases
• Hydrogen breath test to check for small intestinal bacterial overgrowth (SIBO) or problems with carbohydrate digestion, such as lactose intolerance
• Upper GI endoscopy with a biopsy to check for celiac disease
• Colonoscopy to check for colon cancer or inflammatory bowel disease (IBD)

Irritable bowel syndrome (IBS) is treated with changes diet and lifestyle, medications, probiotics, and therapy. 

Dietary changes may include:

• Adding more fiber to the diet
• Avoiding gluten
• Following a low FODMAP diet

Lifestyle changes may include:

• Increasing physical activity
• Practicing stress reduction techniques 
• Getting adequate sleep

Medications used to treat IBS with diarrhea may include:

• Loperamide (Imodium)
• Rifaximin (Xifaxan) 
• Eluxadoline (Viberzi) 
• Alosetron (Lotronex), only for women to be used with special warnings and precautions

Medications used to treat IBS with constipation may include:

• Fiber supplements
• Laxatives
• Lubiprostone (Amitiza) 
• Linaclotide (Linzess) 
• Plecanatide (Trulance) 

Other medications used to treat abdominal pain associated with IBS may include:

• Antispasmodics
• Antidepressants 
• Tricyclic antidepressants
• Selective serotonin reuptake inhibitors (SSRIs)
• Coated peppermint oil capsules