Food Allergies and Intolerances

Some healthcare providers have found that combining the results of  standard allergy tests with an elimination diet has helped those with IC/BPS develop individualized diet plan.

Food Allergies and Intolerances

Guidelines published by the National Institute for Allergy and Infectious Diseases conclude that neither standard blood nor skin tests are sufficient for making a diagnosis of food allergies. However, some healthcare providers have found that combining the results of these standard allergy tests with an elimination diet has helped those with interstitial cystitis.bladder pain syndrome (IC/BPS) develop individualized diet plans that can help control IC/BPS pain and bladder flares.

Urologist John Hubbard, MD and allergist/immunologist C. Steven Smith, MD, from Louisville, Kentucky, are studying the link between allergies and IC/BPS. In addition to seasonal allergies, the team is finding that food allergies are also common in IC/BPS patients.

Dr. Smith estimates that 35 to 40 percent of IC/BPS patients he sees have genuine food allergies, based on the results of their skin-prick tests and elimination diets. He found that their IC/BPS symptoms decreased when they removed those foods from their diets.

A Small Number of People with IC/BPS Need to be Gluten-free

Gluten FreeMore than 1,000 people with IC/BPS completed an Interstitial Cystitis Association (ICA) quick poll on gluten sensitivity and celiac disease:

  • 12 percent of IC/BPS patients reported being diagnosed with celiac disease, a gluten-intolerance disease.
  • 15 percent of IC/BPS patients stated that foods with gluten bothered their IC/BPS symptoms.

These findings are consistent with research published by the University of Maryland.  They proved that gluten sensitivity and celiac disease are two very different things on a cellular level. This means you can be sensitive to gluten which can cause IC-related symptoms, without having celiac disease.

A group of researchers at Baylor College of Medicine in Houston, Texas also studied the link between IC/BPS and gluten intolerance in a group of 39 IC/BPS patients. Their findings report a strong connection between gluten sensitivity and IC symptoms in this group of patients. Participants in this study also reported that a gluten-free diet was helpful for controlling IC/BPS symptoms.

Other allergists and immunologists report that some IC/BPS patients feel a gluten-free diet is helpful, especially if they have irritable bowel syndrome (IBS) symptoms or are prone to skin issues, such as unusual rashes.

An elimination diet which restricts common sources of gluten, such as foods with wheat, rye, barley, semolina, and couscous (breads, pasta, cereals, cookies, and much more), can give you some clues as to whether to keep gluten in your diet.

There are different degrees of gluten sensitivity. Some people with IC/BPS only need to limit food containing gluten while others may need to follow a very strict gluten-free diet (avoiding not just foods but products, such as toothpaste and lipstick, which may contain hidden sources of gluten).

Sticking with a gluten-free diet is tough. The good news is that today there are many gluten-free products, cookbooks, and recipes, as well as alternative whole grains that are easy to prepare, such as amaranth, quinoa, and buckwheat. Like with any other food group, whole foods are best for your overall health, so try to stay away from processed gluten free products like cookies, snack foods, etc.

Lactose Intolerance: Only Those with Lactose Intolerance Need to Restrict Dairy Products

There has been NO research suggesting people with IC/BPS have a higher risk for lactose intolerance.

Lactose is a type of sugar found in milk and dairy products. Some people have trouble digesting lactose. When they drink milk or eat a milk product, they feel bloated and may experience diarrhea and gas. Many people with lactose intolerance can enjoy small amounts of milk and dairy products without any difficulty. However, level of lactose tolerance varies greatly from person to person, so if consuming dairy seems to make your IC/BPS symptoms worse, you may want to consider getting your calcium and vitamin D from other IC/BPS-friendly sources:

  • Lactose-free, almond or rice milk with as few ingredients as possible
  • Nuts and seeds (almonds, peanuts, sesame seeds)
  • Legumes (chickpeas, kidney beans, white beans)
  • Canned fish with bones (canned salmon, canned sardines)
  • Fish (Atlantic perch or rainbow trout for calcium; tuna and salmon for vitamin D)
  • Hard cheese (mild)


Bloating or swelling of the belly (“IC/BPS belly”) is a common complaint among people with IC/BPS. Excess gas and distention of the abdomen may worsen IC/BPS symptoms. Research suggests that many things can cause bloating. A buildup of gas in your GI tract may be due to eating foods that tend to produce gas, such as beans and sodas. The pain of bloating may be due to increased sensitivity of nerves in the abdomen. And, bloating can be a side effect of opioid medications. If you have swelling in your stomach or pelvic area, talk with your healthcare provider. Get checked to make sure that the swelling is not a sign of infection or some other medical problem.

There are dietary changes you can make to help limit bloating:

  1. Reduce or eliminate beverages that cause gas such as carbonated drinks and beer, which tend to be bothersome for most IC/BPS patients.
  2. Reduce your intake of beans, Brussels sprouts, cauliflower, cabbage, and other cruciferous vegetables.
  3. Limit any dairy products that can trigger lactose intolerance symptoms.
  4. Try the FODMAP elimination diet, if you have IBS.
  5. Ask your doctor about probiotics.