What is Food Intolerance?
Food intolerance is a condition where the body cannot properly digest or process certain nutrients in food, such as lactase enzyme deficiency that helps digest lactose sugar, or an excessive sensitivity to certain chemicals in food.
The symptoms usually directly involve the digestive system, such as bloating, abdominal pain, diarrhea, or nausea, and generally do not involve an immune system response like typical food allergies.
Differences Between Food Intolerance and Food Allergy
The key differences between food intolerance and food allergy lie in the mechanisms, symptoms, and severity. Understanding these factors helps us better prevent and avoid risks.
|
Criteria |
Food Intolerance |
Food Allergy |
| Mechanism | The body cannot fully digest or absorb certain foods, often related to enzyme deficiencies. | Caused by an abnormal immune response to food proteins, triggered by Immunoglobulin E (IgE). |
| Relation to food quantity | Small amounts usually do not cause symptoms or cause mild symptoms. | Even small amounts can cause severe symptoms. |
| Symptom onset | Symptoms usually develop gradually within a few hours or may take several days after eating. | Symptoms occur rapidly, within minutes to 1 hour after eating. |
| Common symptoms | Bloating, abdominal pain, diarrhea, frequent gas, headache, chronic itchy rash, fatigue. | Itchy rash, hives, swelling of mouth/face/throat, difficulty breathing, asthma, shortness of breath; severe cases may cause anaphylaxis. |
| Severity | Reduces quality of life but usually not life-threatening. | Ranges from mild to severe and can be life-threatening. |
| Initial care | Avoid or limit foods that trigger symptoms. | Strictly avoid allergenic foods and carry Epinephrine injection for emergencies if there is a history of anaphylaxis. |
Foods That Commonly Cause Symptoms from Food Intolerance
Food intolerance can occur from various types of food. Knowing which foods are likely to cause symptoms helps in monitoring and adjusting diet appropriately. Common foods include:
- Dairy products such as cheese, yogurt, or ice cream are the most common causes, especially in Asians. This condition results from lactase enzyme deficiency that digests lactose sugar, causing bloating, abdominal pain, or diarrhea in sensitive individuals.
- Grains such as wheat, barley, and rye are another group that can cause symptoms due to sensitivity to gluten protein, leading to bloating, abdominal pain, or fatigue after consuming bread, pasta, cereal, or baked goods.
- FODMAPs which are short-chain carbohydrates that often ferment in the intestines and produce gas, causing bloating, fullness, or diarrhea, especially in people with irritable bowel syndrome (IBS). Foods in this group include garlic, onions, wheat, various beans, high-fructose fruits like apples and pears, and honey.
- Food additives such as sulfites used as preservatives in wine, dried fruits, or canned foods, as well as monosodium glutamate (MSG) and some food colorings, can trigger food intolerance symptoms. Sensitive individuals may experience allergy-like symptoms.
- Natural bioactive substances such as histamine found in fermented foods like red wine, aged cheese, as well as fish, tomatoes, and avocado; salicylates found in fruits, vegetables, herbs, and some spices; and caffeine in coffee, tea, and energy drinks, which may cause palpitations, headaches, or stomach irritation.
Is It Food Intolerance? Testing and Monitoring
Many people confuse symptoms of food intolerance with food allergy. If unsure or concerned about symptoms, consult a doctor for evaluation to determine if symptoms are likely due to food intolerance as follows:
- IgG antibody blood test (IgG Food Antibody Test): When the body reacts to food, elevated IgG levels may indicate a tendency toward food intolerance to that food. However, IgG test results should be evaluated comprehensively with symptoms and patient history by a doctor or specialist.
- Hydrogen breath test to assess the ability to digest lactose sugar, a major cause of food intolerance.
- Elimination diet where the patient avoids suspected foods for a period, then gradually reintroduces them one at a time to observe the body’s response. This method helps accurately identify the specific food causing symptoms.
Food Intolerance Test Results and Their Use in Health Planning
Understanding the body’s reactions to each food is beneficial for health planning as follows:
- Avoid or limit foods that the body reacts strongly to for a period (using an elimination diet) of about 3-6 months to allow the digestive system to rest and recover. Then gradually reintroduce foods in small amounts while observing symptoms to find the tolerable quantity.
- If certain foods must be avoided, choose nutritionally similar alternatives. For example, if dairy products cannot be consumed, plant-based milks such as almond, oat, or soy milk fortified with calcium and vitamin D can help prevent nutritional deficiencies.
- Plan holistic health care by recording daily food intake alongside symptoms to analyze relationships and improve dietary adjustments effectively, along with maintaining health through regular exercise, adequate sleep, and stress management, which support better digestive function.
- Risk prevention such as reading food labels to avoid potential triggers like lactose, sulfites, or MSG, and controlling ingredients and seasonings when preparing food at home.
Symptoms from food intolerance should not be overly concerning if properly diagnosed and managed. Knowing trigger foods and adjusting diet and lifestyle can help you live a quality life and reduce discomfort. If you suspect you have food intolerance, you should get tested and seek advice from a specialist doctor.
At Elite Lifestyle Wellness Center Phyathai Phaholyothin Hospital, we provide comprehensive services from consultation, analysis, to guidance on appropriate dietary adjustments to help you confidently plan your diet and health care, focusing on maximum benefits for both physical and mental health for a happy life.
FAQ: Frequently Asked Questions About Food Intolerance Testing
Q: How often should food intolerance be tested?
A: Frequent testing is not necessary if you have adjusted or avoided foods according to test results and symptoms improve continuously. Repeat testing is usually considered when reassessing symptoms or if new symptoms related to other foods arise.
Q: Does the food intolerance test cover all types of food?
A: The test covers food groups likely to cause intolerance such as milk and dairy products, gluten, nuts, eggs, and some fruits and vegetables, but does not cover all foods.
Q: How many foods can a food intolerance test detect?
A: It depends on the test kit used. Generally, basic tests cover 40–100 foods, and comprehensive tests cover 200–300 foods. Selection should be based on symptoms, nutritional history, and doctor’s advice.
Q: If the test result is normal but symptoms persist, what should I do?
A: If no food intolerance is detected, symptoms may be due to other causes such as food allergy, irritable bowel syndrome (IBS), or other digestive health issues. You should consult a doctor for further evaluation and diagnosis.
Dr. Kobkulya Jungprasertsri
Director of Anti-Aging Medicine Center
Phyathai 2 Hospital and Phyathai Phaholyothin Hospital
