Explain-Food Allergies, Sensitivities and Intolerances

Food “allergies, sensitivities and intolerances”.

Many people confuse these terms or assume they mean the same thing. However, they describe three different conditions:

Immune-Mediated Reactions (Body’s Defence System Reacts)

1. IgE-Mediated Food Allergy:
the immune system mistakenly identifies a specific food protein (antigen) as harmful. Immunoglobulin E (IgE) antibodies attack the antigen, triggering the release of histamine and other inflammatory chemicals.

* Symptoms: hives, swelling, difficulty breathing or anaphylaxis ect.

* Reaction Time: instant to 30 minutes.

* Prevalence: only 5% of adverse food reactions are caused by IgE-mediated food allergies.

2. Non-IgE-Mediated Food Allergy:
a different immune pathway causes inflammation, primarily affecting the gut.

* Symptoms: reflux, nausea, vomiting, abdominal pain, bloating, gas, diarrhoea, or constipation. May lead to serious gut conditions.

* Reaction Time: Several hours to days.

3. Food Sensitivity:
a subtle immune response involving IgG, other Ig’s or T-cells.

* Symptoms: Fatigue, migraines, heartburn, bloating, irritability, gas, cramps, runny nose, or skin issues.

* Reaction Time: 30 minutes to 3 days.

4. Celiac Disease:
an autoimmune condition where the body attacks itself after consuming gluten.

* Symptoms: Diarrhoea, stomach cramps, nausea, and vomiting.

* Reaction Time: 30 minutes to 2 hours.

Non-Immune-Mediated Reactions (No Immune Involvement)

Example: Lactose Intolerance
occurs when the body lacks the enzyme lactase, leading to undigested lactose fermenting in the gut.

* Symptoms: gas, bloating, diarrhoea.

* Reaction Time: 30 minutes to 2 hours.

Key Difference: Antigen vs. Antibody

* Allergies & Sensitivities: the immune system treats food (antigen) as harmful, producing antibodies to fight it.

* Intolerances: no immune response. The problem lies in missing enzymes or poor food absorption.

What is the association with Autism Spectrum Disorder (ASD)?

A study found a significant association between ASD and a higher prevalence of reported allergies, including food (11.25% vs. 4.25%), respiratory (18.73% vs. 12.08%), and skin allergies (16.81% vs. 9.84%) compared to children without ASD. An earlier study also reported elevated levels of IgA, IgG, IgM, and IgE in children with ASD, along with imbalanced T-cell function, suggesting potential immune system dysregulation in ASD.

When in Doubt? Observe & Test

If your child shows symptoms, track their meals and consult a healthcare professional. Elimination and challenge diets are crucial for detecting the 95% of adverse food reactions that are non-IgE-mediated.

References:

Xu G, Snetselaar LG, Jing J, Liu B, Strathearn L, Bao W. Association of Food Allergy and Other Allergic Conditions With Autism Spectrum Disorder in Children. JAMA Netw Open. 2018 Jun 1;1(2):e180279. doi: 10.1001/jamanetworkopen.2018.0279. PMID: 30646068; PMCID: PMC6324407.

Lucarelli S, Frediani T, Zingoni AM, Ferruzzi F, Giardini O, Quintieri F, Barbato M, D'Eufemia P, Cardi E. Food allergy and infantile autism. Panminerva Med. 1995 Sep;37(3):137-41. PMID: 8869369.