hunger, eating and health Flashcards Preview

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Flashcards in hunger, eating and health Deck (27)
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1
Q

mouth and salivary glands

A

mastication/chewing and saliva (alkaline)

2
Q

oesophagus

A
  • transporting food to stomach

- set up for alkaline conditions as stomach is acidic

3
Q

stomach

A
  • churning food and breaking it down

- acid digestive enzymes

4
Q

liver/gall bladder

A

-additional enzymes added to small intestine

5
Q

pancreas

A

-produces insulin and glucagon to store and release energy

6
Q

small intestine

A

-absorbs nutrients

7
Q

large intestine

A

-removes water and packs waste

8
Q

rectum/anus and bladder

A

store and expels waste

9
Q

pancreatic hormones

A
  • insulin: shifts carbs from blood–>storage (glycogen, proteins)
  • glucagon: shifts fuel from storage to where it is needed (glycogen–>proteins, carbs, frees fat stores to use as fuel when glucose low)
10
Q

why is our intake so complex?

A
  • we are omnivorous
  • diet includes range of key elements that our bodies have evolved to process
  • lots of variation between species e.g. number of stomachs
  • some variation within species e.g. dairy/gluten tolerance
11
Q

what is the outcome of digestion?

A
  • lipids/fats–>fats - largest + most efficient energy store
  • amino acids–>proteins - mostly in form of muscle tissue
  • glucose–>glycogen - stored in muscles and liver, fast release
  • minerals + vitamins–>body structure e.g. bones, cell structure
12
Q

how do we ensure these outcomes of digestion occur?

A
  • homeostasis/set point theory - when we’re running low on food we experience: hunger and craving
  • brain sensitive to shortage of glucose (hypothalamic regulatory nuclei)
  • liver sensitive to shortages of glucose + lipids
  • stomach sends signals to brain via release of ghrelin
13
Q

why does eating go wrong sometimes?

A
  • internal factors e.g. learning, emotions

- environmental factors e.g. toxic environments

14
Q

homeostasis

A

when running low on fuel
-hunger (motivational state) due to low levels of fatty acids+glucose
-craving (automatic behavioural state)
body corrects by releasing glucose + taking in more food

15
Q

why do we feel full/satiety?

A

short term satiety signals: adequate glucose + lipid levels detected in brain + liver

  • stomach distension- swollen
  • buccal activity - lots of chewing
  • high levels of sensory stimulation - big on taste + smell
  • appetite suppressant chemicals e.g. caffeine, amphetamines
  • diet products try to offset adequate levels with these factors
16
Q

what does research say about the brain and satiety?

A
  • some research says hypothalamus is centre for satiety
  • recent evidence suggests there isn’t such
  • looks like it is hormonally controlled: ghrelin, neuropeptide Y, serotonin
17
Q

what hormone do fat tissues secrete? function?

A

leptin

  • increases body metabolic rate
  • decreases food intake by desensitising brain to hunger signals + inhibiting the effect of other hormones that drive eating
18
Q

what is the satiety cascade?

A

sensory(beliefs)–>cognitive–>post-ingestive(stomach+intestines)–>post-absoptive(liver+metabolites)

19
Q

health implications from poor eating:

A

nutritional deficits: scurvy, rickets, Korsakoff’s syndrome
starvation effects either immediate, long-term or both:
-concentration
-socially withdrawn
-physical + mental development stunted
-emotional instability
-all physical systems
starvation effects can pass to generations
-obesity in child of starved mothers

20
Q

obesity

A
  • affects multiple systems e.g. social functioning
  • strong link to premature mortality
  • related to specific problems in children e.g. bullying
21
Q

what are the factors that oppose homeostasis?

A
  • genetics
  • learning
  • social learning
  • social pressures
  • food industry
  • ‘toxic environment’
22
Q

genetic/evolutionary factor

A
  • genetic factors make us more likely to eat certain foods
  • predisposed to high energy, high-taste foods
  • less likely to enjoy bitter
23
Q

learning factor

A

-learned taste preferences and aversions influenced by culture, upbringing, satiety to specific foods(e.g. eat a varied diet)

24
Q

social learning factor

A
  • we eat in a number of ways that match people around us
  • imitation of how/amount/speed
  • cultural influence
25
Q

social pressures/environmental factors

A
  • lighting- eat more in dim light
  • temperature - eat more when cold
  • smells
  • location of food
26
Q

agriculture and food industry

A
  • food industry goes through stages in level of positive/toxic influence
  • ensuring we’re not starved due to increasing pop- Malthusian hypothesis
  • toxic rn: cheap, unhealthy food sold in large quantities, healthy foods out of season
  • high fructose corn syrup related to obesity
27
Q

toxic environment factor

A
  • in cultures where food scarce–>obesity valued as status symbol + vice versa
  • evolved to grab food bc high-energy was only seasonally available h/e now it is abundant and easier to get
  • unhealthy foods cheap, exercise–>screens