To eliminate food reactions, it helps to know if your symptoms are caused by an allergy, a sensitivity or food intolerance.
Food has the power to nourish and heal us, but when it disagrees with our bodies the result can be just the opposite – pain, fatigue, digestive issues and more. Even if you think you’re eating a clean diet, you may be sensitive to foods considered healthy. Everyone is different, so it’s essential to understand food allergies, sensitivities and intolerances to find your personal triggers. What are the differences and how do you identify offending foods? Let’s break it down…
Food Allergies
Allergic reactions happen when your immune system overreacts to something that’s normally harmless. A food allergy will trigger symptoms immediately or within a few hours after eating. With an allergy, IgE (immunoglobulin E) antibodies lead to a release of histamine and other chemicals that make up an allergic response. Symptoms can range from mild to life-threatening and may include coughing, tingling in the mouth, skin reactions like hives or itching, nausea, vomiting, stomach pain, trouble breathing, dizziness, fainting or anaphylaxis requiring treatment with epinephrine. When you have a food allergy, there’s no way to predict how your body will react when you’re exposed. You might have a mild reaction one time and a severe reaction the next. The most common food allergens are dairy, soy, wheat, peanuts, tree nuts, shellfish, fish and eggs. There are no treatments to eliminate food allergies so avoiding allergy-causing foods will prevent symptoms. Read food labels carefully and know all the ingredients in the foods that you plan to eat. You should also wash your hands and any surfaces you touch to prevent accidental contact.
Food Sensitivities
Food sensitivities are more common than food allergies. Food sensitivities cause immunoglobulin A and G (IgA and IgG) reactions where the immune system produces antibodies that spark the body’s inflammatory processes. These types of reactions don’t happen immediately, making it tough to tie them to specific foods. Symptoms may come on up to 72 hours after exposure to a food trigger. A food sensitivity may cause allergy-like symptoms such as rashes and asthma, as well as cramps, constipation, diarrhea, headaches, brain fog, migraines and more. It’s possible that people may have IgA or IgG sensitivities for years and never realize it because they don’t connect a food with the symptoms.
Food sensitivities are often related to increased gut permeability, AKA leaky gut. This can happen when the lining of the gut is compromised. If the intestine is permeable, microscopic food particles travel through the walls of the gut lining and cross into the bloodstream where they are detected by the immune system kicking off an inflammatory process. Unfortunately, that’s why these types of sensitivities tend to be foods that you regularly eat.
Food Intolerances
A food intolerance occurs when the body lacks the enzymes needed to digest what you’ve eaten, like lactose to break down dairy. Symptoms of a food intolerance tend to be more digestive and include nausea, stomach pain, gas, cramps, bloating, vomiting, heartburn and diarrhea. However, sometimes they may cause headaches or irritability. While food allergies and sensitivities may require avoiding offending foods entirely, a food intolerance may allow you to consume small amounts of it and not feel an effect.
Common Triggers
Gluten
More people than ever are going gluten-free. But who should eliminate gluten and why? While we typically think of gluten as being in wheat products, gluten is a protein also found in other grains such as barley, rye and couscous. Other grains such as oats, corn and rice that don’t naturally contain gluten may come in contact with gluten-containing grains in the fields and during processing. So, if you’re going to eat grains and want to avoid gluten, look for certified gluten-free products. Gluten is also found in many processed foods such as lunch meat, vegetarian meat substitutes, soy sauce and most salad dressings. Gluten is used as a thickener, emulsifier and gelling agent in candies, ice cream and seasonings.
Celiac Disease
Gluten reactions can be due to celiac disease or non-celiac gluten sensitivity. When someone with the autoimmune condition celiac disease consumes gluten, it triggers an immune reaction in the small intestine. Over time, the intestine can become damaged and unable to absorb nutrients. The most common symptoms of celiac disease include diarrhea, fatigue, weight loss, bloating and anemia. For some, the reaction can even be life-threatening. A portion of those with celiac disease may believe they are asymptomatic. However, upon eliminating gluten, they might report improvement in symptoms previously thought to be unrelated like acid reflux, bloating and gas. Celiac disease can be diagnosed with a blood test or an intestinal biopsy. The biopsy is considered the gold standard but blood tests can give an indication. In addition, DNA tests may show a genetic propensity to celiac disease with the presence of the genes HLADQ2 and HLA-DQ8.
Non-Celiac Gluten Sensitivity
Non-celiac gluten sensitivity is a term used to group all other reactions to gluten that aren’t autoimmune in nature. Those with gluten sensitivity may experience leaky gut leading to increases in other food sensitivities. If you’re sensitive to gluten, you may notice symptoms similar to celiac disease or Crohn’s disease, such as bloating, abdominal pain, diarrhea and gas. You may also notice fatigue, brain fog, joint pain, headaches, skin problems, anemia and mental health challenges. If your body reacts negatively to gluten, it’s best to avoid it entirely. One study showed that it can take as long as six months for signs of gluten exposure to no longer be detectable in blood tests.
Dairy
Along with gluten, dairy is often a major trigger for digestive distress, inflammation, skin reactions and congestion, among other possible effects. These reactions can be an allergy, sensitivity or an intolerance. A dairy intolerance may be due to inadequate digestive enzymes needed to break down lactose. In fact, it’s estimated that only about 35 percent of the global population can digest lactose over the age of seven or eight. Digestive enzymes containing lactase may be used to help digest lactose.
Nightshades
Nightshades are a botanical family of foods and spices such as tomatoes, potatoes, eggplant, bell peppers, cayenne and paprika, that contain chemical compounds called alkaloids. The term “nightshade” may have originated because some of these plants prefer to grow in shady areas, and some flower at night. While these foods contain important nutrients, some people report experiencing inflammation, pain or gastrointestinal symptoms after eating them. These reactions are caused by the alkaloids in the plant – designed to protect against pests while growing. While it’s possible to have an actual allergy to foods in the nightshade family, some of us just lack the proper enzymes to digest these foods. This may lead to inflammation in the gut and digestive issues. The alkaloids in nightshades have also been linked to leaky gut and inflammatory bowel disease.
Oxalates
Many nutrient-rich plant foods contain oxalic acid, or oxalates. The list includes items considered super foods such as leafy greens, berries, beans and tea. Oxalic acid protects plants from insects and disease, but oxalate foods can be a problem for some of us. They can interfere with the absorption of vitamins and minerals such as iron and calcium. Oxalates bind to calcium and create oxalate crystals, which can cause kidney stones and block calcium absorption. These crystals can also travel through the body and cause muscle pain.
High-oxalate foods include spinach, broccoli, cauliflower, oranges, chocolate, kale and nuts. However, you can reduce the oxalate content in your food by cooking vegetables or soaking nuts and seeds for 12 hours then roasting them for 15-20 minutes.
Keep in mind, not everyone is affected by oxalates. However, those with certain conditions such as recurrent kidney stones, leaky gut syndrome, irritable bowel syndrome, inflammatory bowel disease, small intestinal bacterial overgrowth (SIBO), autoimmune disease, nutrient deficiency or chronic inflammation should follow a low oxalate diet.
Histamines
We typically associate histamines with seasonal allergies and use antihistamines to calm the reaction. But foods may also contain histamines that kick off an allergic-type reaction in some people. Those with an impaired ability to metabolize ingested histamine may experience reactions that include diarrhea, headache, nasal symptoms, asthma, hypotension, arrhythmia and flushing. Research attributes this to low levels of diamine oxidase, or DAO, the primary enzyme for metabolizing histamine.
Foods high in histamine include aged and fermented items such as cheeses, yogurt, sauerkraut, processed meats, vinegars, alcohol, avocados, legumes, citrus, chocolate, some nuts, tomatoes, bananas, eggplant, spinach and leftovers. Leftovers? Yes, the histamine level in foods increases the longer they have been left out.
If you’re experiencing what are believed to be histamine reactions, consider following a low-histamine diet. Some foods on a low-histamine diet include organic, grass-fed meats, fresh wild-caught fish, apples, blackberries, blueberries, coconut, and macadamia nuts.
Fodmaps
Many people with irritable bowel syndrome find they react to foods in a class called FODMAPs, short for fermentable oligosaccharides, disaccharides, monosaccharides and polyols. In some people, the small intestine absorbs these short-chain carbohydrates (sugars) poorly, causing symptoms such as cramping, diarrhea, constipation, bloating, gas, weight loss and malabsorption.
It’s often caused, or exacerbated by, small intestinal bacterial overgrowth, or SIBO. Bacteria is normally present in the large intestine with small amounts in the small intestine. SIBO is defined as excessive bacteria in the small intestine. When the bacteria ferment the sugars in the intestine, an individual may experience gas, bloating, diarrhea, constipation and malabsorption.
To reduce symptom, consider trying a diet low in FODMAP foods. Some examples of low FODMAP foods include blueberries, strawberries, carrots, zucchini and eggs, Avoid high FODMAP items such as sugar in all forms, beans, garlic, onions, avocados, apples, and grains like wheat.
Uncover Possible Culprits
Finding your own food sensitivities and intolerances isn’t always straightforward. Sometimes, it’s clear that certain foods provoked a reaction. But often, we may not link specific foods to seemingly unrelated health concerns. To find your personal food sensitivities, consider the following:
- Try an Elimination Diet
An elimination diet is considered the gold standard for finding food sensitivities and also helping heal the gut. However, it takes patience. In a typical elimination diet, you eliminate certain foods for about three weeks and then slowly bring them back one at a time. The Institute for Functional Medicine recommends removing the following foods: corn, dairy, eggs, gluten-containing grains (barley, rye, spelt and wheat), white sugar, shellfish, soy, beef, pork, processed meats, and caffeine. Instead, focus on eating vegetables, fruit, organic, cold-pressed oils (avocado, grapeseed, olive and coconut), lean meats and fatty fish, legumes, nuts, seeds and non-gluten whole grains. For success, be sure to have plenty of approved foods on hand, plan your meals, carefully read all labels and drink six to eight glasses of water daily. After the elimination phase, bring back eliminated foods one at a time, with each reintroduced food spaced out over two days. Keep a food diary of what you eat and carefully watch for any reactions. - Get Tested
• Blood testing determines allergies to specific foods by measuring IgE antibodies. Food sensitivities are determined by measuring IgG or IgA antibodies. However, there’s debate about the accuracy of such tests. Some believe that the presence of antibodies may not signal intolerance, but rather, that the patient has merely been exposed to certain foods. Zonulin levels can also be measured by a blood test and is an effective method to determine leaky gut.
• Skin testing involves pricking the skin with a lancet with a drop of an allergen extract and observing the surface reaction. Skin prick tests are helpful for IgE allergies but may not be as accurate for IgG or IgA because those reactions can be delayed. Given uncertainty about the accuracy of these types of tests, most functional medicine doctors use an elimination diet.
• Microbiome labs, which analyze a stool sample, break down the composition of your gut bacteria, helping pinpoint an imbalance. Imbalances in gut bacteria are linked to food sensitivities and 70-80 percent of the body’s immune cells are found in the gut.
• A breath test will reveal small intestinal bacterial overgrowth (SIBO) which occurs when bacteria overgrows up from the large intestine into the small intestine. SIBO may make you more sensitive to certain foods, such as those high in FODMAPs.
• Organic Acids Test (OAT) will measure oxalate metabolites in the urine. Metabolites, also known
as organic acids, are products of the body’s metabolism and are excreted through urine.
Heal Your Gut
Once you’ve identified your food triggers, adjust your diet to avoid the offending foods. Depending on what the underlying cause of your reaction is, it’s possible that you may not need to eliminate them forever. The following steps have the potential to help heal the gut to the point where you may be able to reintroduce eliminated foods.
- Remove – Eliminate anything that negatively affects the gut, such as trigger foods, parasites, yeast and bacterial overgrowth.
- Replace – Add items that may be deficient and that help with digestion, including digestive enzymes, hydrochloric acid or bile acids.
- Reinoculate – Encourage the growth of beneficial bacteria with probiotic foods (such as yogurt, miso and tempeh), probiotic supplements and prebiotics. Prebiotics feed probiotics and are found in a fiber called inulin. For inulin, eat foods such as garlic, onions, artichokes, flax and oats.
- Repair – Next, heal the lining of the gastrointestinal tract with nutrients such as zinc, vitamins A, C and E, fish oil and the amino acid glutamine.
- Rebalance – Balancing lifestyle factors such as sleep, exercise and stress will help you maintain a healthy gut.
Summary
If you suffer from food allergies, sensitivities or intolerances, take steps to understand the nature of your reactions by trying an elimination diet, keeping a food diary and running lab tests. Then customize your diet, and ideally, address any underlying causes. With time, there’s hope that you may be able to, once again, enjoy excluded foods.