Food intolerances are more common than many realize and can significantly impact health and wellbeing. Unlike food allergies, which involve the immune system, intolerances primarily affect the digestive system and occur when the body has difficulty breaking down certain foods. Let’s explore some of the most common food intolerances, their causes, symptoms, and management strategies.
Dairy
Lactose, a sugar found in milk and dairy products, is broken down in the body by an enzyme called lactase. For those with lactose intolerance, a shortage of lactase enzymes leads to an inability to digest lactose, resulting in digestive symptoms such as abdominal pain, bloating, diarrhea, gas, and nausea.
This widespread condition affects an estimated 65% of the world’s population. Diagnosis can be made through lactose tolerance, lactose breath, or stool pH tests. People with lactose intolerance are advised to avoid dairy products like milk and ice cream. However, aged cheeses and fermented products like kefir, which contain less lactose, may be more tolerable.
Gluten
Gluten is a protein found in wheat, barley, rye, and triticale, and it is associated with conditions such as celiac disease, non-celiac gluten sensitivity, and wheat allergy. Celiac disease is an autoimmune disorder where gluten exposure triggers the immune system to attack the small intestine.
On the other hand, wheat allergies involve the production of antibodies against wheat proteins. Some people also experience non-celiac gluten sensitivity, a milder intolerance estimated to affect 0.5–13% of the population. Symptoms can include bloating, abdominal pain, diarrhea or constipation, headaches, fatigue, joint pain, skin rash, and depression or anxiety. Both celiac disease and non-celiac gluten sensitivity are managed with a gluten-free diet, which excludes foods like bread, pasta, cereals, beer, and baked goods.
Caffeine
Caffeine is a bitter chemical found in coffee, tea, soda, energy drinks, and chocolate, and it is known for its stimulating properties. While most adults can consume up to 400 mg of caffeine daily without adverse effects, some individuals are hypersensitive to caffeine due to genetic factors or a reduced ability to metabolize it.
Unlike a caffeine allergy, which involves the immune system, hypersensitivity can cause symptoms such as rapid heartbeat, anxiety, jitters, insomnia, nervousness, and restlessness, even after consuming small amounts. Those sensitive to caffeine should limit their intake of caffeine-containing foods and beverages.
Salicylates
Salicylates are natural chemicals plants produce as a defence mechanism found in fruits, vegetables, teas, coffee, spices, nuts, and honey. While most people tolerate normal amounts of salicylates, some are highly sensitive and experience adverse reactions like stuffy nose, sinus infections, nasal and sinus polyps, asthma, diarrhea, colitis, and hives.
Although it’s impossible to eliminate salicylates from the diet, sensitive individuals should avoid foods high in salicylates, such as spices, coffee, raisins, and oranges, as well as cosmetics and medications containing these compounds.
Amines
Amines and histamine are natural compounds produced during food storage and fermentation. Histamine plays essential roles in the immune, digestive, and nervous systems but can cause problems for those who cannot break it down effectively.
Impaired enzyme function may lead to histamine build-up, triggering symptoms like flushing, headaches, hives, itching, anxiety, stomach cramps, diarrhea, and low blood pressure. People with histamine intolerance are advised to avoid high-histamine foods such as fermented products, cured meats, aged cheeses, citrus fruits, avocados, smoked fish, vinegar, and fermented alcoholic beverages like beer and wine.
FODMAPs
FODMAPs—short-chain carbohydrates found in many foods—are poorly absorbed in the small intestine and ferment in the large intestine, causing gas, bloating, and discomfort. These compounds can also draw water into the digestive system, leading to diarrhea.
Symptoms, which include bloating, abdominal pain, constipation, and diarrhea, are prevalent in people with irritable bowel syndrome (IBS). A low-FODMAP diet has been shown to reduce symptoms in up to 86% of people with IBS. Foods high in FODMAPs include apples, soft cheeses, honey, milk, artichokes, bread, beans, lentils, and beer.
Sulfites
Sulfites, often used as preservatives, can be found in dried fruit, wine, canned vegetables, pickled foods, potato chips, and baked goods. Some people, particularly those with asthma, are sensitive to these chemicals and may experience hives, skin swelling, stuffy nose, low blood pressure, flushing, diarrhea, wheezing, and coughing.
In severe cases, sulfite sensitivity can lead to life-threatening airway constriction. The FDA mandates labeling foods containing sulfites to help sensitive individuals avoid them.
Fructose
Fructose, a simple sugar found in fruits, vegetables, honey, and high-fructose corn syrup, can cause digestive distress in individuals with fructose intolerance. In these cases, fructose isn’t efficiently absorbed into the bloodstream; instead, it ferments in the large intestine and causes symptoms like reflux, gas, diarrhea, nausea, abdominal pain, vomiting, and bloating. Fructose malabsorption is often associated with other FODMAP sensitivities, and a low-FODMAP diet may help manage symptoms. High-fructose foods to avoid include soda, honey, apples, watermelon, cherries, and sugar snap peas.
Manage Common Food Intolerances with Gut Clarity
Understanding and managing food intolerances can significantly improve quality of life. If you suspect a food intolerance, consult a healthcare professional for testing and personalized advice.