6.3 - Effects of diet on alimentary canal

what meals move through the alimentary canal at what pace

large meals cause greater stretching and faster movement

high protein/fat meals slow movement

alcohol/caffeine stimulate movement

how does constipation occur

if large intestine movements reduce and contents remain there for a long time, absorbing more water and making faeces darker and harder, and possibly painful to defecate

what causes constipation

lack of roughage (cellulose/insoluble fibres), lack of excersise, emotional problems

what happens in diarrhoea

irritation of intestines increases peristalsis, leading to frequent defecation of watery faeces without enough water absorbed

what are causes of diarrhoea

bacteria

viruses

parasites

cancer

coeliac

lactose intolerance

what can severe diarhhoea lead to

dehydration and death

why is soluble fibre important

it can only be found in pectins, gums, and mucilage

it lowers cholesterol, decreases risk of heart disease and cancer, and helps blood glucose levels

it traps fats in intestine

what is bowel cancer

uncontrollable growth of cells in wall of large intestine

what increases risk of bowel cancer

diet high in red/processed meat and low in soluble fibre, alcohol, smoking, obesity

what is coeliac

the inability to tolerate gluten

what happens if someone with coeliac consumes gluten

their immune system damages their villi and nutrients can’t be absorbed

what are symptoms of coeliac

varied symptoms, malnourishment, muscle cramps, joint pains, nausea

how do you get coeliac and what is the cure

coeliac is inherited, only cure is to follow gluten free diet