Feeding and appetite Flashcards
define hunger
physiological process of feeling hunger
define appetite
feeling of hunger - can be influenced by hunger or other factors
define satiation
state where stomach is satisfied and someone stops eating
define satiety
the feeling between your last immediate meal and the next
satisfaction/fullness
what is basal metabolic rate
the rate at which the body uses energy while at rest to maintain vital functions such as breathing and keeping warm.
what happens to food stuffs in digestion
food stuffs are broken down into simple molecules so that they can be utilised by the body
where does digestion start
starts in the mouth- enzymes start the process in the mouth
what are the main components of food
macronutrients
protein= essential amino acids
carbohydrate= glucose
fat- fat (lipid)
what happens when macronutrients are broken down
which when they are broken down they turn to essential dietary components
what are amino acids used for in the body
building blocks of human proteins
what are carbs used for in the body
broken down into glucose which is a vital energy source
what is fat used for in the body
fat = lipids
essential for things like replenishment of fatty membranes surrounding our neurons and blood brain barriers
what do humans report when unable to chew
lower levels of satisfaction
what role does chewing play for hunger and satiety
not a very important role- could be more linked to social and psychological factors
what type of urge do we have to chew
biological urge
how is chewing evolutionary adaptive
allows primates/humans to consume hard, otherwise uneatable foods
energy cost is involved
how is taste evolutionary useful
humans can make judgements about the food they consume by taste e.g. is the food spoiled
how does taste sure we get a wide range of nutrients
taste allows us to widen food types we like
these nutrients cares always positive
what other than taste can lead to over eating
large packages and containers - more likely tot eat it all
what are the 5 taste types
- sweet
- sour
- salty
- bitter
- Umami (savoury)
what is released from the pancreas in repose to carbohydrates
insulin
what does insulin do to blood glucose
converts excess blood glucose to glycogen to be stored in the liver
how is insulin involved with amino acids
transportation of amino acids which in turn facilitates protein synthesis
how is insulin involved with fats
transports fats to adipose cells/ tissues for fat storage
what does glUCAGON aid in
conversion of fat stores into free fatty acids and provides energy
what is the difference between glucagon and glycogen
Glucagon is a hormone that signals the body to convert glycogen into glucose,
while glycogen is a stored form of glucose
what is involved in the process called Gluconeogenesis
between meals or fasting the pancreas releases glucagon which breaks down glycogen which is stored in the liver
what key hunger hormone is produced by the stomach
Ghrelin
what is Ghrelin release correlated with
ghrelin release is correlated with stomach contractions
Ghrelin and the lateral hypothalamus
in the lateral hypothalamus ghrelin will trigger increased hunger via elevated amounts of orexins and neuropeptide Y (NPY)
what blocks satiety actions in the hypothalamus
NPY and GABA
where in the stomach is ghrelin released
gastrointestinal tract in response to an “empty stomach” - the point it starts to contract
what do orexins do
support the motivation to eat and may be linked to the more pleasurable/additive qualities of food
what is adipose tissue
also known as body fat or fat tissue, is a connective tissue that stores energy, insulates the body, and cushions organs. It’s found under the skin, between organs, and in bone marrow
what hormone does adipose cells produce
Leptin
what is leptin
leptin Is a more long-term regulation feedback mechanism of energy monitoring
it monitors fat stores in the body
what does leptin correlate with
leptin correlates with the level of adipose tissues - more body fat more leptin
how can leptin and adipose tissue feedback to the body
if there is little fat it can indicate the body is staring and needs for sustenance or go into energy conserve
what do high levels of adipose and leptin signal
amble nutrition and therefore the body will desire to eat less
what do low levels of adipose and leptin signal
low levels of nutrition and the body will indicate starving and energy saving
what are the 2 areas of hypothalamus involved in feeding and appetite
ventromedial hypothalamus
lateral hypothalamus
what happens when there is lesions on the ventromedial hypothalamus
hyrerphagia (over eating)
what happens when ventromedial hypothalamus is stimulated
aphasia (under eating)
where is the satiety centre
VMH- leads to feelings of fullness in an individual
what happens when there is lesions on the Lateral Hypothalamus
aphagia (under eating)
what happens when LH is stimulated
hyperphagia (under eating)
where is the hunger centre
lateral hypothalamus
explain the psychological factor habit
3 meals a day Is a cultural factor that is conditioned in us
humans don’t need 3 meals a day its not evolutionary
biological feedback mechanisms become conditioned
explain psychological factor learned behaviours
eating as a reward e.g. finish dinner so you can get desert
emphasises we don’t see food as just an energy source
there’s a social benefit to eating and drinking with others
explain psychological factor motivated choice
people eat certain diets and food choices for a whole host of reasons e.g. veganism, health, socioeconomic status, environment
emotions e.g. stress
health, sensory appeal, price, familiarity all depend on demographic fcators
explain psychological factor food halo
overestimating healthiness of a food item usually based on a single character e.g. low fat
children are more vulnerable to this bias
explain psychological factor self control and inhibition
“self-control” refers to the ability to regulate one’s thoughts, emotions, and behaviors, particularly in the face of temptations or impulses, while
“inhibition” is the specific act of actively suppressing or restraining an impulse,
explain psychological factor self licensing
mindless eating vs mindful eating
allowing a treat is good for a persons motivation, well being and overall success f health behaviours
diet starts monday= self licensing
psychological factor accessibility and proximity
increased proximity to fast food outlets in deprived areas inc risk of obesity in children but not adults
product placements + special offers play a big role e.g. impulse buys
explain behavioural/nudge tactics
package size, plate shape, lighting and variety can influence volume of food consumed
explain social element in feeding and appetite
adults will typically eat more when in the company of others
social norms cab influence self perception/ sensory appeal of food
what is the gut- brain axis
bidirectional communication network in which motivations, cognitions and mental states can influence gastrointestinal process
when individuals experience negative emotions- how does this impact food eaten
negative feedback- more likely to eat higher amounts of refined sugar, saturated fats or other engird dense foods
what has saturated fat and sugars been shown to do to the microbiome
reduce the diversity which means more room for bad strains of bacteria
what happens when there is a change in your microbiota
alter ability to digest foods and the preference of foods you wish to consume
what nerve connects gut and brain
vagus nerve
how does obesity develop
when energy intake exceeds expenditure
what can cause high fat diet in adults
methylation
