Understanding Food Intolerance and Food Allergy
Learn the difference between food intolerance and food allergy, their symptoms, causes, and management tips to help you identify and handle food-related reactions effectively.

Written by Dr. Mohammed Kamran
Reviewed by Dr. Rohinipriyanka Pondugula MBBS
Last updated on 4th Sep, 2025

Introduction
Have you ever eaten something and felt uncomfortable afterward, maybe bloated, gassy, or even sick? You might wonder: Is this a food allergy or just intolerance? While both can cause unpleasant reactions, they are very different. Let’s break it down in simple terms so you can understand the difference, recognize symptoms, and take the right steps for better health.
What’s the Difference Between Food Intolerance and Food Allergy?
To better understand food-related reactions, it’s important to know the key differences between food intolerance and food allergy.
Food Intolerance
Food intolerance happens when your digestive system struggles to break down certain foods. It’s not an immune system reaction, meaning your body isn’t fighting the food like an enemy; it just has trouble processing it.
Common Examples:
• Lactose intolerance (difficulty digesting milk sugar)
• Gluten sensitivity (not the same as celiac disease)
• Histamine intolerance (found in aged cheese, wine)
Food Allergy
A food allergy is an immune system reaction where your body mistakes a harmless food as a threat and attacks it. This can lead to serious, even life-threatening symptoms.
Common Allergens:
• Peanuts, tree nuts
• Shellfish, eggs
• Milk, soy, wheat
Consult an Allergist and Immunologist for the best advice
How to Tell Them Apart: Symptoms Compared
Recognizing the symptoms can help you distinguish between food intolerance and food allergy more clearly.
Food Intolerance Symptoms
• Bloating, gas, stomach pain
• Diarrhoea or constipation
• Headaches
• Fatigue
• Mild skin reactions (rashes)
These symptoms usually appear hours after eating and are rarely dangerous.
Food Allergy Symptoms
• Swelling of lips, face, or throat
• Hives or itchy skin
• Trouble breathing, wheezing
• Dizziness, fainting
• Severe vomiting or diarrhoea
Allergic reactions can happen within minutes and may lead to anaphylaxis, a medical emergency requiring immediate treatment (like an epinephrine shot).
What Causes Food Intolerance and Allergies?
Understanding the underlying causes can help explain why food intolerance and allergies occur.
Causes of Intolerance
• Enzyme deficiency (e.g., lactase for lactose intolerance)
• Sensitivity to food additives (MSG, sulphites)
• Irritable Bowel Syndrome (IBS)
Causes of Allergies
• Genetics (family history increases risk)
• Immune system overreaction
• Early childhood exposure (though some allergies develop later)
How to Manage Food Intolerance
Managing food intolerance often involves dietary adjustments and lifestyle changes to reduce discomfort and improve well-being.
1. Identify Problem Foods – Keep a food diary to track what triggers discomfort.
2. Try Elimination Diets – Remove suspected foods for a few weeks, then reintroduce them one by one.
3. Use Enzyme Supplements – Like lactase pills for dairy intolerance.
4. Choose Alternatives – Lactose-free milk, gluten-free grains.
How to Handle Food Allergies
Handling food allergies requires careful planning and precaution to avoid triggers and stay safe.
1. Avoid Allergens Strictly – Read labels carefully and ask about ingredients when eating out.
2. Carry an Epinephrine Auto-Injector (if prescribed) for emergencies.
3. Inform Family & Friends – Ensure they know how to help in case of a reaction.
4. See an Allergist – For proper testing (skin prick or blood tests).
When to See a Doctor
Consult a doctor:
• If you suspect an allergy (especially with severe reactions).
• If symptoms persist despite dietary changes.
• For proper diagnosis, self-diagnosing can be risky.
Final Thoughts
Food intolerance and allergies may seem similar, but their causes and risks are very different. While intolerance can be managed with diet adjustments, allergies require caution and medical guidance. Listen to your body, seek help when needed, and enjoy eating without worry!
Consult an Allergist and Immunologist for the best advice
Consult an Allergist and Immunologist for the best advice

Dr. Anand Ravi
General Physician
2 Years • MBBS
Bengaluru
PRESTIGE SHANTHINIKETAN - SOCIETY CLINIC, Bengaluru

Dr. Akhila Hb
Paediatrician
10 Years • MBBS, MD ( PAEDIATRICS), Fellowship in Asthma and Allergy
Bengaluru
Apollo Medical Center, Marathahalli, Bengaluru
(50+ Patients)

Dr Abilash Jain
General Physician/ Internal Medicine Specialist
12 Years • MBBS,DNB(FM),MNAMS,FIAMS,CCGMG(GERIATRICS),DGM (GERIATRICS),PGCD(DIABETES,BOSTON UNIVERSITY),FID(DIABETICS UK)CCEPC(PALLIATIVE CARE),CCCC(CRITICAL CARE)
Visakhapatnam
Apollo Clinic Vizag, Visakhapatnam
Dr. Renu Saraogi
General Physician/ Internal Medicine Specialist
21 Years • MBBS, PGDFM
Bangalore
Apollo Clinic Bellandur, Bangalore
(225+ Patients)
Dr. E Prabhakar Sastry
General Physician/ Internal Medicine Specialist
40 Years • MD(Internal Medicine)
Manikonda Jagir
Apollo Clinic, Manikonda, Manikonda Jagir
(125+ Patients)
Consult an Allergist and Immunologist for the best advice

Dr. Anand Ravi
General Physician
2 Years • MBBS
Bengaluru
PRESTIGE SHANTHINIKETAN - SOCIETY CLINIC, Bengaluru

Dr. Akhila Hb
Paediatrician
10 Years • MBBS, MD ( PAEDIATRICS), Fellowship in Asthma and Allergy
Bengaluru
Apollo Medical Center, Marathahalli, Bengaluru
(50+ Patients)

Dr Abilash Jain
General Physician/ Internal Medicine Specialist
12 Years • MBBS,DNB(FM),MNAMS,FIAMS,CCGMG(GERIATRICS),DGM (GERIATRICS),PGCD(DIABETES,BOSTON UNIVERSITY),FID(DIABETICS UK)CCEPC(PALLIATIVE CARE),CCCC(CRITICAL CARE)
Visakhapatnam
Apollo Clinic Vizag, Visakhapatnam
Dr. Renu Saraogi
General Physician/ Internal Medicine Specialist
21 Years • MBBS, PGDFM
Bangalore
Apollo Clinic Bellandur, Bangalore
(225+ Patients)
Dr. E Prabhakar Sastry
General Physician/ Internal Medicine Specialist
40 Years • MD(Internal Medicine)
Manikonda Jagir
Apollo Clinic, Manikonda, Manikonda Jagir
(125+ Patients)