Question

What is the difference between food allergy and food intolerance? Describe the characteristics of Type 1 Hypersenstitvity.

Answer 1

 

Food intolerance:

• It mainly affects the digestive system.
• It has to do with the inability to break down food either due to insufficiency of enzymes or malabsorption.
• The symptoms include the digestive symptoms like abdominal pain, diarrhea or gas formation. 

Food allergy: 

• It affects the immune system and triggers the immune response to food allergens which are normally harmless but in particular person they cause harm.
• The symptoms vary from itching, leads to high fever, affecting respiratory and digestive systems.
• It can be dangerous and also sometimes life threatening.

Type 1 Hypersensitivity characteristics:

• Allergy (to drug, food, animal, skin, dust) , all these are Type 1 hypersensitivity reactions.
• Antigens which stimulate these allergies are called Allergens which are non microbial.
• Relatives of allergic individuals are more likely to have allergies than unrelated people(genetic background). 
• Hygiene hypothesis ( due to environmental conditions)- increased hygiene and under exposure to pathogens are the factors which contribute to this.
• Atopy is another type 1 hypersensitivity reaction, which refers to IgE mediated hypersensitivity.
• Patients with these reactions are known as atopic patients.
• Atopic reactions are either localized or systemic.
• Localized reactions means it is confined to an organ system, affect a specific target tissue which includes allergic asthma, eczema, hay fever, etc.
• Systemic reactions affect the whole body, which includes anaphylaxis (life threatening reactions).
• Treatment of atopic reactions include avoidance of known allergen.
• Localized atopic reactions are treated by antihistamines and systemic reactions are treated by epinephrine.

 

• Allergies are more common is areas that have low levels of helminth infestations because  people in developed countries have less exposure to microbial infections like bacteria, viruses, and helminths which causes abnormal natural immune development, and this finally results in the higher incidence of allergy compared to people in developing countries.

                                         This is the "Hygiene hypothesis".