science of marketing food and elimination diets

Question 1

what is the difference between an intolerance and an allergy

Answer 1

an intolerance takes place in the Gi tract and is caused by an enzyme deficiency. Whereas an allergy can be induced by very little food and always involves the immune system

Question 2

describe the pathophysiology of lactase persistence

Answer 2

1. Metabolised into 2 sugar units in the small intestine
2. Glucose and galactose monomers are transported into the blood circulation by the Na2+/glucose transporter
3. No lactose molecules in the colon

Question 3

describe the pathophysiology of lactose intolerance

Answer 3

1. Lactose transits undigested into the large intestine
2. Gut bacteria metabolise lactose and results in fermentation – produces gas (Co2, H and methane), results in bloating, pain & flatulence
3. This raises the osmotic pressure in the colon
4. Increases flow of water into the lumen of the colon causing “osmotic diarrhoea” associated with lactose intolerance

Question 4

what is the difference between a primary lactase deficiency and a secondary lactase deficiency

Answer 4

primary is genetically inherited caused by an absence of lactase persistent allele. Whereas secondary lactase deficiency is caused by damage of the lining of the intestine

Question 5

how can you diagnose lactose intolerance

Answer 5

1. hydrogen breath test
2. lactose tolerance test
3. therapeutic options

Question 6

name and describe what are the different types of allergic reactions

Answer 6

Type I hypersensitivity: reactions involving igE antibody against soluble antigen, triggering mast cell degranulation.

Type II hypersensitivity: reactions involve IgG and IgM antibodies directed against cellular antigens leading to cell damage

Type III hypersensitivity: reactions involve IgG and IgM occasionally IgA antibodies with antigen to form a complex. Leads to tissue damage

Type IV hypersensitivity: reactions are T-cell-mediated reactions that involve tissue damage mediated by activated macrophages by other immune system effectors.

Question 7

what is the difference between class 1 and class 2 food allergies

Answer 7

class 1 are oral allergens such as eggs whereas class 2 are areoallergens causes sensitisation in the respiratory tract

Question 8

describe food allergies pathogenesis

Answer 8

1. upon first exposure to allergen. APC processes antigen and presents it to TH2 cells.
2. B cells proliferation and differentiate into plasma cells that synthesise and secrete IgE antibody
3. TH2 cells release IL-4 and IL-12 which activate B cell
4. IgE binds to mast cells by Fc region sentitizing the mast cells
5. upon subsequent exposure to allergen mast cells with IgE bind to antigen and release inflammatory molecules

Question 9

what are food elimination diets

Answer 9

they have a food intolerance to keep monitor their symptoms when they eat specific food

Question 10

what is a FODMAP diet

Answer 10

diet of food elimination looking to eliminate specific foods which can trigger IBS