Food Chemicals or FODMAPs, What's Your IBS Trigger?

So you have just been just been diagnosed with Irritable Bowel Syndrome (IBS) and you’ve been told that to manage your symptoms you need to change your diet. Not everyone with IBS has the same symptoms or food triggers, which means the way you change your diet needs to be individualized to your specific needs.

IBS is a functional condition where the bowel looks normal, but doesn’t function normally, resulting in symptoms of bloating, cramping, excess wind, diarrhea or constipation or a combination of the two. Once you have had medical causes of these symptoms excluded by your doctor, the next step is to see a Registered Dietitian who will assess your symptoms, your medical history, your diet and your suspected triggers to determine which dietary intervention is most suitable.

The low FODMAP diet is one method that has received a lot of attention lately and with good reason, it can work for up to 75% of people with IBS. However, what if you are one of the 25% that it doesn’t work for? You may be interested to know that there are other types of food intolerances that can also trigger IBS type symptoms for different reasons. One of the approaches I use a lot in my practice and I have found to be extremely successful is the RPAH Food Chemical Elimination Diet.

What is the Failsafe or RPAH Food Chemical elimination diet?

Chemicals occur everywhere in nature, including in the food we eat and the water we drink. In the 1970’s the allergy unit at the Royal Prince Alfred Hospital in Sydney, Australia, became aware of certain chemicals that occurred naturally in foods, which appeared to be related to skin irritation in sensitive people. Through their research they discovered that people’s sensitivity levels can vary and that symptoms range from skin irritation, rashes, eczema and hives, airway and sinus problems, headaches and anxiety and gastrointestinal symptoms like IBS.

Over time the dietitians and allergy doctors at RPAH developed an elimination diet that excluded naturally occurring food chemicals in the forms of salicylates, amines and glutamates as well as artificial colors, additives and preservatives. They found that when foods containing these molecules were removed from the diet, symptoms subsided but when foods were re-challenged the symptoms returned.

Where are natural food chemicals found?

Natural food chemicalsWhere they're found
SalicylatesStrawberries, tomato, kiwifruit, citrus, pineapple, mint, toothpaste, herbs and spices, nuts and seeds, tea, soft drink, salad dressings, and some cooking oils
AminesRipe bananas, tomato, pineapple, citrus, grapes, bacon, aged meats and cheeses, canned fish, soy sauce, miso, wine, and beer
GlutamatesDried fruit, spinach, collard greens, fermented vegetables, processed meats, dressings, gravy, stock, beer, and wine

Salicylates, amines and glutamates are also found in aspirin and a wide range of artificial colors, flavor enhancers, preservatives and artificial antioxidants.

Who is this diet for?

The best way to identify if the RPAH elimination diet is right for you is to be assessed by a Registered Dietitian who has experience in food intolerances. Since IBS is variable your individual pattern can provide clues:

  1. Your symptoms and medical history provide relevant information. In most cases people who are sensitive to food chemicals will have sensitive to a range of foods, dust and medications. Symptoms also often extend beyond bowel and abdominal problems to other body systems, they may also be bothered by smells, hayfever, migraines or dermatitis. Sensitivities also tend to run in families, so it’s worth talking to other family members about these typical gut and non-gut symptoms. The presence of one or more of these other symptoms or a family history may indicate that food chemical sensitivities are responsible.
  2. Diet and suspected food triggers is the other part of the equation. Some people are able to identify specific problematic foods, however, because symptoms are often delayed or build up of several days, detecting these can be very confusing. Whether or not you are able to pinpoint certain food triggers, your dietitian will look at what you eat on a regular basis. If it is food chemicals causing your symptoms, he or she would expect to see foods containing these molecules as a regular part of your diet.

How to start the RPAH elimination diet?

The first and most important step is to see your doctor. It is important to exclude medical conditions like Celiac Disease, IBD (e.g. Crohn’s and Colitis), certain cancers and other disorders that can affect proper gut functioning before changing your diet.

The RPAH elimination diet is a diagnostic tool that is intended to be used to pinpoint the foods that trigger your symptoms and then allow you to modify your long term diet, to allow as much variety as possible, while still managing your symptoms. It is conducted in four phases:

  1. Elimination
  2. Challenges
  3. Liberalization
  4. Long term management

How a dietitian can help you through the 4 phases

The RPAH elimination diet is complex and quite restrictive. You are much more likely to succeed, get accurate results and streamline the process if you see a dietitian who is experienced in who is familiar with the diet. Your dietitian will work closely with you thought-out all stages of the diet.

Your dietitian will assess you

Since getting results hinges on being on the right plan, this is the most important aspect of commencing any elimination diet. A multitude of people can tell you what diet worked for them or how to follow a diet, but an experienced Registered Dietitian can look at your symptoms, your medical history, your eating and lifestyle patterns to determine which diet is the one that will work best for you.

Your dietitian will help you implement the plan

The baseline RPAH elimination diet can be implemented in three ways, Simple, Moderate and Strict. On top of this certain people, especially if there are bowel symptoms, also need to exclude wheat, dairy and soy. Your dietitian will work with you to customize an elimination diet that is right for you and your symptoms.

This is a complicated diet and it is easy to make mistakes, your dietitian will work with you on meal planning, label reading and guidelines to make transitioning to the elimination diet as smooth and seamless as possible.

Knowing what to expect and troubleshooting

Many people experience “withdrawal” symptoms, and knowing what to expect and how to manage this can significantly reduce stress. An experienced registered dietitian will make sure there are no surprises or misconceptions, will know when to trouble shoot and when to persist. He or she will also have strategies to minimize symptom flares.

Tailor the challenge phase

You don’t find out if you react to a food by excluding it, you find out by doing challenges. There are many factors that can cloud results, when you challenge a food you need to be sure that it is the food and not something else triggering symptoms. Your dietitian will tailor challenges and guide you through this process, so that you get accurate results, and know with certainty which chemicals you are sensitive to and which ones you tolerate in large amounts.

Liberalization and long term plan

This is the most exciting phase and where you get to expand your diet to include more variety again. By now you will have a good understanding of food chemicals, your level of tolerance and what symptoms your individual reactions involve. During these phases of the diet, your dietitian will help you to interpret these results and apply them to your day to day life and food choices in a meaningful way. This will enable you to have as much freedom and variety as possible while still keeping symptoms managed.

Nutritional balance

All elimination style diets restrict food choices and potentially put you at risk of nutritional deficiencies. Your dietitian will make sure your diet remains nutritionally balanced throughout the process, and help create a long term plan to ensure optimal long term health and wellbeing.

Final thoughts

Having a food sensitivity does restrict your choices somewhat, but it doesn’t mean you can’t enjoy eating and sharing food with friends and family, stay well and lead a full life. Remember your sensitivities and symptoms may be quite different to what your friends or family experience. It can be tricky to manage, but knowing what foods affect you and cause you the most distress is worth the effort and give you the ability to get back to enjoying life without IBS getting in the way.

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This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.

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