Food Intolerance Vs. Food Allergy
There’s a lot of provider and patient misunderstanding about the differences between an intolerance/sensitivity versus an allergic reaction to food and we’ve created this article to help demystify the confusion between reactions and testing.
As the saying goes, “you are what you eat.” What if the foods you are eating cause symptoms, worsen inflammation, and end up making you feel worse?
There are 3 types of reactions to food in which your immune system accidentally identifies the protein of that food as the enemy and attacks it.
First, is the autoimmune response leading to a lot of different symptoms and possibly damage. The most commonly known condition for this is celiac disease where there is an autoimmune response to gluten and gliadin. This testing is typically done through blood work and/or small bowel biopsy. There's a lot of primary care providers and specialists who are confused over how to diagnose celiac disease. Some patients are told they do not have celiac disease without the proper guidlelines for testing. We follow the Mayo Clinic guidelines and one of the focuses of our practice is on helping patients get the proper testing to get the right answer about whether or not they have celiac disease.
Second is the Type I immediate IgE hypersensitivity immune response commonly known as a food allergy. This reaction typically occurs very quickly (minutes to hours) after eating an offending food and symptoms range from mild to severe. Many are aware of food allergies causing anaphylaxis (the most common example being peanuts and kids) but they may also experience itchy lips/tongue/throat, stuffy nose, headaches, belly ache, diarrhea, gas, bloating, skin reactions, and sudden fatigue. This test is typically done through the blood however most adults have their ‘trigger food’ figured out because the reaction is so quick. If ice cream causes immediate diarrhea, or strawberries create lip swelling, and peanuts close your throat – one does not easily forget. It's usually fairly obvious because the symptoms occur so quickly to the offending food. When testing is necessary, we do run IgE food panels to help patients when it's more difficult to figure out which food it is as some may have multiple allergies. IgE testing is ran through any standard laboratory.
Third is the non-immediate (delayed) IgG and IgA response commonly known as a food intolerance or food sensitivity. This differs from an immediate IgE food allergy response in that symptoms may not show up for hours or days making it difficult to pinpoint exactly what foods are causing what reaction in the body especially as people tend to eat the same foods over and over. Symptoms of food intolerances/sensitivities include: sore throat, stuffy nose, congestion, headaches, belly aches, constipation, diarrhea, gas, bloating, hormone issues, foggy head, headaches, weight gain, fatigue, joint pain, depression, behavior changes, anxiety, and skin issues. How do you know if dairy products cause your mental fogginess or gluten causes fatigue or almonds increase your acne if you eat them everyday?
Testing for IgG and IgA food intolerances/sensitivities is confusing for many healthcare providers as they are not typically trained on this type of reaction as it is neither obvious nor life-threatening, however intolerances and sensitivities are gaining public awareness as people are removing offending food groups in order to help support autism/spectrum disorder treatment plans, chronic diseases, and reduce inflammation in the body with success. Unfortunately though, there is some conflicting evidence on the comparison of IgG versus IgE and the testing behind it. Keep in mind that they are different ‘branches’ of your immune system and being allergic to a food doesn’t mean you are intolerant and vice versa.
Some negative press and studies have come out recently concluding that IgG intolerance testing has no validity or value. However, when we and others have reviewed all the research against food intolerance testing, the studies routinely point out that when someone withdraws a particular food based on IgG testing results and that food is then re-introduced, there are no immediate symptoms to cause concern. However, as we just discussed the nature of IgG and IgA mediated responses is that they are low and slow and may take hours to days to show. It’s not a rash you can measure, nor a sudden asthma attack you can clearly see. It might be overall fatigue that slowly worsens, a headache that develops 24 hours later, behavior issues that occur, or several poor night’s sleep. The studies also highlight that providers who use IgG testing use it as an ‘absolute’ test in that all positive markers must never be eaten again. We, at Sherwood Family Medicine, choose to use the test a little differently due to our experience and training.
The food intolerance/sensitivity test serves as a guideline to help patients determine the top foods to rotate out of the diet in order to ‘clean house’ and get healthier before re-introducing it at a later date. Typically, when we identify the intolerance, we have a patient stop the food completely for a full four to six weeks (and in some cases much longer) to evaluate what has improved before even considering eating it again. Some people find the re-introduction brings an immediate return of symptoms and should therefore not be eaten ever while others find an offending food is ‘okay’ at small doses or at infrequent intervals. There is no ‘black and white’ with intolerance/sensitivity testing which is why we run the test as a good place to start.
While there is no gold standard IgG test, in our clinical experience the food intolerance/sensitivity testing we use can be a great tool. Our providers have been doing them for a number of years. We have been able to use the results to help guide patients in a reasonable way that makes sense to systematically remove certain food(s) to help figure out the root cause of some of their lifelong symptoms. Does it work? Yes, very often it does however, it is not right for everyone as we understand it can be difficult to eliminate your favorite foods and some patients aren’t ready to make those changes. For those who are ready to go deeper, find answers and come out with a stronger, more balanced, healthy body then it is worth it.
We regularly receive patient testimonials about the life changing effects the test and subsequent elimination has created. Patients whose chronic headaches disappear, PMS balances out, depression lifts, fatigue improves, sleep resumes, joint pain eases, skin rashes go away, behavior changes for the better, bloating diminishes, weight loss occurs, bowels become regular and more. These same patients report complete return of symptoms by eating the offending food(s) however it may not show up for hours to days which is why clinical trials can be so difficult to fully assess. We know this is important work, as patients have referred many of their friends and family to get intolerance/sensitivity testing done.
If you are interested in a deeper root cause approach to your symptoms, getting tested for you and for your family may make sense. Talk to your provider about it today. Like us on Facebook and check to receive all feeds to connect with us to get the latest updates about food allergies and intolerance. Call us to talk to a provider that will work collaboratively with you to help figure your food issues out. Remember, you are what you eat. We're here to help!