Eating Behaviour Flashcards
outline the evolutionary approach to explain the eating behaviour
- Early diets- high fat as they didn’t know when next meal would come, meat for brain development, sweets because of minerals and vitamins
2-Taste aversion- response to eating spoiled or toxic, advantageous to ancestors, discovered rats learnt to associate the food with the illness of poison
3.Neophobia- reluctance to try new/different foods
evaluate evolutionary explanations for eating behaviour
- Preference for sweet foods- Alaska, the Inupiat people, never exposed to sweets, but developed a liking and taste for them when introduced- shows its innate
- RWA- Bernstein and Webster, gave cancer patients a new flavour of ice cream before chemo, they then associated the chemo sickness with the ice cream
- Knapila- 468 pairs of twins, found heritability was at 67%
- Not adaptive anymore
role of learning in food preference
Social influences
-Parents- first exposure to food, found a correlation between parents and children in terms of body dissatisfaction. Parents manipulate the availability of food
-Peers- Greenhalgh- found peer observation can be pos and neg, children exposed to pos modelling were more likely to try new food and be healthy, Birch sat kids with new peers at lunch, found children develop a pref for healthy food
Culture
-Media- has influence but we put it into the context of our lives, age, location, income
-Meals- a huge rise in takeaways. Maguire found 45% increase in fast food restaurant in 18 years
evaluate the role of learning in food preferences
- Most research is limited and only on white US families. Robinson studied 8000 9 years old from different backgrounds, found complex association between parent behaviour and child’s food
- Limited effectiveness- a lot of modelling fails, there was a study that asked parents about how they model food, most were found to be ineffective. Methods to promote healthy food worked
- RWA- adverts, restrictions in certain countries about unhealthy food
- Chen and Yang- studied tweets about food, the signif association between healthy food choices and the number of grocery food shops nearby. No association between number of fast food places and unhealthy food choices, we are able to resist
neural and hormonal mechanisms
-Homoeostasis- how your body maintains a stable internal environment and optimal energy conditions
-Lateral hypothalamus- a decrease in glucose leads to hunger. Found in the 1950s when scientists stimulated rates LH and they started to eat. When the rats were injected with neuropeptide y, they kept eating even after they were full.
Ventromedial hypothalamus- increase in glucose, stop eating, damage to this cause over eating, hyperphagia
-Ghrelin- stimulates appetite, increases if bodily mechanisms are low
-Leptin- reduces hunger, and breaks down fat
evaluate the neural and hormonal mechanism
- May not be adaptive- doesn’t anticipate or prevent energy deficits. Homoeostasis means we eat at our optimum level, but in the past, we needed to eat over this in case we lack food for a few days. Lacks a buffer
- Lateral hypothalamus- over simplistic, damage to this doesn’t just affect hunger, but also thirst and sex, not the eating centre we once thought. Research suggests eating behaviour is more controlled by neural circuits in the brain
- Support for hypothalamus- damage to ventromedial hypothalamus resulted in hypophagia and obesity in many species. Ventromedial hypthalaum is the satiety center with the para-ventricualr nucleas having a large role
- Leptin resistance- when it fails to control appetit the receptors arent functionging, need more
bio explanations for AN
Genes
-Families- person with a first-degree relative with AN is ten times more likely to develop it
-Twin studies- heritability at around 58%
-Nature or nurture- adoption, disentangle genes from environment, Klump, 123 adopted sibling pairs and 56 bio pairs, estimates from 59-82%
Neural
-Serotonin- disturbances=AN. Bailer found women recovering from binge eating and purging had higher serotonin than healthy control and restricting ones
-Dopamine- over activity in dopamine levels in the basal ganglia. Dopamine plays a part in harm/pleasure which shows why AN sufferers don’t associate food/eating with pleasure
evaluate bio explanation for AN
- Ignores the role of media, young girls seek out thin model pictures to reinforce body images. One study found over a 16-month period girls with AN, had an increase in magazine consumption
- RWA- some states don’t accept AN as a biological problem so sufferers don’t get insurance
- Serotonin- SSRIs are ineffective when treating AN, but it does help in relapse
- Reduced stigma
- Dopamine- sufferers are found to blink more, associated with high levels of dopamine
family systems theory of AN
Psychosomatic family
- Enmeshment
- Autonomy
- Control
- Rigidity
- Lack of conflict resolution
evaluate family systems theory of AN
- Gender bias- only focus on women and their daughters, ignores the role of father and we can’t generalise to males, suggests it always has a maternal origin. Dysfunctional mother
- Manzi- found a difference between family factors that promote emotional development and those that stifle it. Enmeshment is rooted in manipulation and control, so is therefore negative. Things like cohesion have positive effects within a family
- Latzer and Gaber- told parent and daughter to pick out areas of disagreement, but it can’t be about food or diet, found they couldn’t pick topics nor resolve them
- A lot of studies have failed to find psychosomatic family traits in patients with AN, so is it even relevant. Families are diverse and different cant general to all of them.
social learning for AN
- Modelling
- Reinforcement- “wow you look great”
- Maternal model- mothers are more influential than the father. Hill found similarities between mother and daughter eating habits as young as 10 years old. Smolak found mothers who complain about their weight are more likely to have a daughter who worries about weight
- Peer influence- found a link between peer influence and the use of unhealthy diets, like purging and pills. Gender difference, overweight girls and underweight boys
- Media influence- self-objectification
evaluate social learning AN
- Found individuals with peers with larger BMIs are less likely to develop AN.
- Becker- Fijian girls, found introduction of tv increased AN and of desire for Western body type
- Pike- although mothers and daughters influence each other, there was no link between that and restrained eating
- No link found for tv and AN but there is for AN and fitness mags
cognitive theory for AN
distortions and irrational beliefs
- Cognitive behavioural model- Garner and Bemis- self-doubt, perfectionist, this coupled with cultural ideals, person thinks weight is most important thing about them, avoidance becomes the norm, isolated
- Transdiagnostic model of AN- Fairburn- EDs due to self-control, same set of cognitive distortion, referred to as core psychology, any failure will make them feel out of control
evaluate cog theory of AN
Lang- children with and without AN, found no difference in IQ, but the AN ones displayed inefficient and inflexible processing style. Couldn’t overcome beliefs when presented with new facts
- Garner and Bemis found AN sufferers have a bias towards stimuli about food, weight etc. because they are perceived as threatening- selective pre-occupation
- CBT compared to non cog treatment IPT- after 20 weeks 2/3 of CBT groups were in remision but only 1/3 of the IPT was.
- Methodologcial issues- relaince on self-report
bio explanations for obesity
- Twin studies
- adoptions studies
- hypothalamus
- Leptin
- Thrifty gene
