126 terms

Eating Disorders

What is Ruderman and Wilson's explanation for the failure of dieting?
-Restraint Theory
-Conducted a lab study, to explore eating behaviour using a preload/pre test procedure.
-The study involved giving p's either a high calorie prelode or a low calorie preload/
-After eating or drinking the preload, p's were asked to take part in a taste test - asked to rate different foods on a variety of qualities (sweetness, saltiness and preference).
-P's were then left alone and given a certain amount of time to rate the foods. The amount they ate was also recorded.
-The aim of the preload/taste test was to measure food intake and to examine the effect of pre loading on eating behaviour.
-Restrained eaters consumed significantly more food than unrestrained eaters, irrespective of the size of preload.
What did the restraint theory identify?
-Disinhibition of restraint is a classical characteristic over eating in restrained eaters.
-Disinhibition has been described as 'eating more as a result of loosening restraints in response to emotional distress, intoxication or preloading'.
What are the other characteristics of restrained eaters that may contribute to maintaining a diet?
-Preoccupation with food - may lead to rebound effect from trying to suppress thoughts about food.
-Food can be used to raise mood - linked to the 'what the hell' effect of restrained eaters and low self-esteem.
-The body adjusts to fewer calories being taken in and uses fewer calories - weight loss is slow and motivation is lost.
What is an evaluation of the restraint theory?
-Implications: most weight-loss programmes recommend dietary resstraint, which would seem, on this evidence, to be not good advice. This may ultimatrly lead to obesity.
-Restraint theory cannot explain people who have anorexia nervosa who demonstrate very tight control over their intake. They are exceptionally restrained. This shows that is supports the biological explanation because natural instinct kicks in and makes you eat, where as anorexics have an overdrive in cognition that controls the natural instinct.
What did Herman and Mack do?
-Using the preload/taste-test method, they gave a group of dieters and a group of non-dieters either a high or low calore preload. The results indicated that whereas the non-dieters showed compensatory regulatory behaviour, and ate less during the taste test after the high calorie preload, the dieters consumed more in the taste test if they had had the high calorie preload than the low calorie preload. This form of disinhibition involves overeating in response to a high calorie preload.
What is an evaluation of Herman and Mack's study?
-Although they only studied a fairly small sample, the report of their research was published in a peer-reviewed journal. This paper has been cited widely across the English-speaking world and triggered a new way of thinking about eating behaviour. The impact of this research is probably due to three factors:
*The approach they used was novel, interesting and the findings challenged some of the contemporary ways of thinking about eating behaviour.
*The results demonstrated that trying not to eat could result in overeating - a finding that probably resonated with the personal experience of many researchers, clinicians and lay people alike.
*The study was undertaken in a controlled laboratory setting, giving it some scientific credibility.
What did Wardle and Beales do?
-Carried out an experiment to investigate whether dieting resulted in overeating. They randomly assigned 27 obese women either to a diet group, an exercise group or a control group for seven weeks.
-All participants took part in a laboratory procedure to assess their food intake at weeks four and six. The results indicated that participant in the diet condition ate more than those in the exercise group and also those in the control group, supporting a causal link between dieting and overeating. From this analysis, the overeating shown by dieters appears to be caused by attempts at dieting.
What are some stengths to Wardle and Beales's study?
-An experimental desing: The reseaarchers were able to manipulate whether people dieted, exercised or did neither. Comparisons could therefore be made across the different groups.
-Random allocation: Participants were randomly allocated to the different conditions, so they should have been similar in all other ways, except the type of experimental intervention.
-Laboratory conditions: These enabled eating behaviour to be assessed while other factors were controlled.
-Non student sample: Results could then be generalised to a wider population.
What are two possible causes of over eating?
-The causal analysis
-Mood modification and denial
What is the causal analysis of over eating?
-Herman and Polivy suggested that there is a causal link between dieting and binging.
-'Restraint not only precedes over-eating but contribtes to its causality'.
-The theory that attempting not to eat will increase the probability of you eating.
-(Food is constantly on your mind so more likely to struggle).
What is mood modification?
-The 'making hypothesis'
-It has been found that dieters tend to over eat in response to lowered mood.
-Making their failure of something by over eating.
-Researchers argue that disinhibitory behaviour enables the individual to mask negative moods with the temporary heightened mood caused by eating.
Who tested the 'masking hypothesis'?
-Polivy and Herman
-They found that when p's were told they had failed on a cognitive task, dieters who ate as much as they liked attributed more of their distress to their eating behaviour than to failure on the task.
What are some strengths to Polivy and Herman's study?
-Research places an emphasis on body disatisfaction: which is a common determinant of the ways people eat.
-Use of experimental research: ensuring that key variables are manipulated and conrolled.
-Finding reflect peoples experiences: reflect experiences of many people who have tried to loose weight by limiting what they eat.
What are some weaknesses to Polivy and Herman's study?
-Limitation of restraint as a explanatory theory: How could it explain the eating behaviour of people suffering from anorexia? How do they manage to starve themselves when they spend most of their lives restricting their food intake.
-Laboratory experiment: Most of the studies used to support evidence of dieting has been conducted in a laboratory experiment.
What is the role of denial?
-Cognitive psychology has demonstrated that attempting to suppress or deny a thought frequently has the opposite effect. People report anecdotally that when on a diet or trying to give up smoking, they think about food or smoking more often than usual.
What did Wegner do?
-Asked some participants not to think about white bear and to ring a bell if they did, they told others to think about the bear and ring the bell. He found thos told not to think about the bear rung the bell more.
*'Theory of ironic process of mental control' because it represents a paradoxical effect of thought control.
*According to the theory, dieters attempt to suppress thoughts of foods only serves to increase the dieters' preoccupation with the very foods they are trying to deny themselves. As soon as a food is denied, therefore it simultaneously becomes more attractive.
What are some explanations for dieting success?
-Physical exercise
-Group and individual support
What are some pharmacological's used for weight loss?
-Orlistat = fat is excreted rather than processed into fatty tissue (nasty side effects)
-Sibutramine = involved in regulation of food intake (can increase blood pressure)
What are some surgical techniques used for weight loss?
-Gastric bands: tube between the top of the duodenum, reduces the size of the stomach.
-Both can lead to effective weight loss but with a range of side effects.
What did Ogden do?
-Investigated differences in psychological factors between people who are:
*gaining weight
*obese (stable)
*weight-loss maintainers
-The weight-loss maintainers supported a psychological model of obesity in terms of being motivated to lose weight, e.g. they wanted higher self-esteem and to avoid depression. They were also less inclined to support a medical model of causality, including blaming genes and hormone imbalance.
What research is there to support Ogden?
-Ogden and Hills interviewed people who had successfully maintained their weight loss. Much weight loss was triggered by a major life event. To maintain the weight loss in the long-term a number of sustaining conditions were met:
*a belief in a behavioural model of obesity (a sense of behavioural control - supports TPB model and the notion of free-will)
*a reduction in choice over what and when they eat (no free will)
*a reduction in the benefits and function of eating
*a process of reinvention - creating a new identity as a thinner, healthier person.
-These results suggests it is not only what the person does which helps maintain weight-loss, but what they believe. They must hold the following cognitions:
*have a perception which is in line with a behavioural model of obesity.
*avoid a state of denial whereby they want to eat but do not
*create a situation where food is no longer regarder as rewarding.
*establish a new identity as a thinner person.
What are some AO2 and AO3's to Ogden and Hills's study?
-The emphasis on bodily dissatisfaction, a good common determinant of the ways in which people eat.
-Much of the research has used the experimental method, which enables key variables to be manipulated in a controlled way.
-The findings reflect people's experiences of trying to lose weight by limiting what they eat.
-The restraint theory assumes a link between food restriction and overeating. However, this would not explain how some anorexics (who are certainly successful in controlling their eating!) are high restrictors (restricting anorexia).
-Ignores influence of role models
-Doesn't look at diet plans that people have.
-Individual differences
-Doesn't take biological influences into account.
What are the two parts of biological explanations to eating behaviour?
-Role of neural mechanisms
-Evolutionary explanations
What is the role of neural mechanisms in eating behaviour?
-Homeostasis (involves mechanisms that detect the state of the internal environment and correct it to restore it to its optimum state. The body has evolved two separate homeostatic systems, one for turning eating on and one for turning it off)
*If we are hot - we sweat
*If we are dehydrated - thirsty
*If we need food - hunger
-Homeostasis is maintained via a negative feedback loop: this assumes that all body variables have a set point (or range)
-The digestive tract and the hypothalamus play a significant role in eating behaviour.
What is homeostasis mean?
-Involves mechanisms that can detect and correct.
*Detect: check whether the body has enough nutrients (internal environment)
*Correct: restore the body to its optimal sate.
-Body evolved 2 separate systems in order to cope with the time lag between restoring equilibrium and body registering their effect.
-Turning eating on and turning eating off.
How does homeostasis link with body weight?
-Each individual has a set point and their weight is regulated around that set point.
-Body regulated hunger based possible on:
*Fat stores (lipostatic hypothesis)
*Glucose levels (glucostatic hypothesis)
*Cellular energy: adenosine trisophate (ATP) is a product of the breakdown of macronutrients (fats, carbohydrates and proteins) and considered important for the regulation and maintenance of homeostasis.
What are some evaluating point of homeostasis?
-Homeostasis only reacts to energy deficits. If homeostasis was adaptive it should be ready and prevent a loss of energy before it occurs.
-Homeostasis may be masked by the demands of other human activities. When stressed, we produce extra quantities of gherlin. Gherlin is part of the body;s natural defence against stress as it reduces depressive and anxious behaviours that tend to happen when we are stressed. Ghrelin also boosts appetite leading to increased comfrot eathing therefore; homeostasis would be over-ridden by this stress response.
How does glucose work with the hypothalamus?
-Glucose plays most important role in producing feelings of hinger: a decline in glucose levels activates the lateral hypothalamus which rsults in feelings of hunger causing individual to seek and eat food leading to rise in glucose levels. The rise in glucose levels activated the ventromedial hypothalamus, which leads to feelings of satiation inhibiting further feeding.
How can tumours be used to support the hypothalamus?
-Patients with tumours in the hypothalamus tend to become obese.
-Methods used to research hypothalamus:
*Lesioning in animals
*Investigation of feeding patterns after brain damage
*Effects of neurotransmitters introduced into parts of brain
*Impact of drugs on eating
*Use of fMRI (Functional Magnetic Resonance Imaging)
What is the dual-centre theory of feeding behaviour?
-2 areas of the hypothalamus involved in eating behaviour
*Ventro Medial Hypothalamus (VMH) as a "satiety center"
*Lateral Hypothalamus (LH) as a "Hunger center"
What is the lateral (nucleus) of the hypothalamus (LH)?
-Contains the feeding centre
-This initiates eating
-It responds to decreased blood glucose and increase in gherlin a hormone released from the stomach when it is empty.
What evidence is there to support the lateral of the hypothalamus?
-Anad and Brodeck: Aphagia (this si the term for a failure to eat when hungry) can be caused by damage to the Lateral Hypothalamus in rats. Rats with these lesion will not eat.
-Stellar: Stimulation of this area causes eating behaviour in rats. These opposing effects of injury and stimulation led researchers to conclude they had discovered the 'on switch' for eating.
-Wickens 2000-Neuropeptide Y (NPY) is particularly important for switching on eating. When injected into the hypothalamus of rats NPY causes them to immediately begin feeding even when satiated.
-Stanley found that repeated injections of NPY leads to obesity in rats in a matter of days.
What does the lateral hypothalamus do?
-Researchers discovered damage to LH in rats caused by aphagia
-Aphagia (absence of eating i.e. hunger)
-Stimulation of LH - elicits feeding behaviour - ON switch for eating.
-Neuropeptide Y (NPY) - neurotransmitter found in the hypothalamus
-When NPY injected into hypothalamus of rats it caused them to begin feeding even when satiated (Wickens)
-Repeated injections of NPY produced obesity in just a few days (Stanley).
What are some methodology issues with research done into the lateral hypothalamus?
-Much research in this area has been carried out on animals in laboratories.
-Although the biology of certain brain areas is comparable it is questionable as to the merit of such research. (Can't generalise and compare to humans).
What are some approach issues with research done into the lateral hypothalamus?
-These explanations are still stemming from the biological approach to explaining human behaviour, sometimes with reference to evolution of such behaviours which considers they must also be adaptive.
What is teh ventro medial (nucleus) of the hypothalamus (VHM).
-Contains the satiety centre.
-This inhibits eating behaviour when we are full.
-Responds to:
*an increase in blood glucose,
*a decrease in ghrelin and to CCK (Cholecystokinin), a hormone released when food is detected in the duodenum. It is released into bloodstream during meals (causes reduction in appetite and stiation, suppresses weight gain, leptin a long term satiety signal released by fat cells).
What is some evidence of ventromedial hypothalamus?
-Damage to VMH causes rats to overeat, condition called hyperphagia.
-Stimulation of this area inhibits feeding
-VMH signals, stop eating as glucose receptors in this area
-Damage to nerve fibres passing through VMH possibly damages the paraventricular nucleus (PVN)
-It is this damage to the PVM that causes hyperphagia (Gold)
-PVN also detects specific foods our body needs, feel cravings
What did Hetherington and Ranson do?
-The VMH Rat
-Made lesions on an area of the ventromedial nucleus (part of the hypothalamus) in rats.
-Caused the rats to overeat and be dramatically obese.
-This lesion destroyed a centre that is vital for the control of feeding behaviour. Its destruction led to an increase in feeding and body weight.
-It was assumed that this was a satiety centre - which is normally activated when the animal is full at the end of the meal.
What is some AO2 evaluation of the VMH?
-Designation of the VMH as 'satiety centre' but it could be other factors.
-Gold: lesions to VMH alone does not result in hyperphagia and only produced overeating when included other areas such as the paraventricular nucleus (PVN)
-However, research has failed to replicate Gold's findings
-Animals gained substantially more weight with VMH lesions more than lesions else where.
-Lesions to teh VMH should cause increased appetite and motivation to eat and, increased food intake. Teitalbaum found this was not the case and found rats became lazy and very fussy about the food on offer. They would not eat food that was stale while normal rats would.
-Baylis also found that rats would become obese after two symmetrical leisions in the VMH.
What are some issues of VMH?
-Much of the anumal research involves lesions of areas of the brain or introduction of poisons into the animals brain, sometimes even removal of areas of the brain. It is questionable as to the ethics of this.
What are some debates of VMH?
-These explanations see human behaviour being explained by our nature and do not consider our environment, upbringing or other nurturing factors to explain human eating behaviour.
What is some evidence for the role of ghrelin?
-Cummings et al (2004) monitored PPs' ghrelin levels every 5 minutes
-PPs had to assess their level of hunger every 30 mins.
-In 5 of the 6 participants there was a significant correlation between ghrelin levels, emptiness of the stomach and hunger.
-The results support the theory of the role of ghrelin in eating behaviour
-AO3: The study used a small sample limiting how far the findings can be generalised and it is likely that the participant's subjective judgements of hunger were influenced by expectations of food based on meal times (cultural factors rather than biological factors)
-Ghrelin injections result in increased food intake in animals
-Gastric bands used in treating obesity reduce ghrelin secretion.
What are the 3 main neurotransmitters found to influence appetite?
-3 main neurotransmitters are found to influence appetite:
*Catecholamines (dopamine, norepinephrine, and epinephrine): sympathomimetic "fight-or-flight" hormones that are released by the adrenal glands in response to stress
*Serotonin: found extensively in the gastrointestinal tract, it activates the muscles used for feeding. Is also associated to aggression and "happiness"
*Peptides: short polymers formed from the linking, in a defined order, of α-amino acids
What are some neurotransmitters that increase food intake?
-Norepinephrine (NE) - injections of NE in hypothalamus
*can stimulate feeding if injected into the paraventricular nucleus
*Can reduce feeding if injected into the perfornical area
-Neuropeptide Y (33 amino acid peptide)- high concentrations in the paraventricular hypothalamus and perfornical hypothalamus.
*Rats injected with neuropeptide Y continue eating large amounts of food even when full
*It also seems to cause a preference for carbohydrates
-Galanin (29 amino acid peptide)- particularly found in the paraventricular hypothalamus.
*Injections of galanin into rats cause an increase of food intake and a preference for fats rather than carbohydrates
What did Marie do into the role of neuropeptide?
-Genetically manipulated mice so that they did not produce neuropeptide Y
-Found no subsequent decrease in their feeding behaviour!!
-However, injections of NPY cause hunger...
-...May be due to an experimental artefact, because of the unexpected intake of NPY in experimental conditions (through injection)
What are some neurotransmitters and modulators that decrease food intake?
-Cholecystokinin (CCK) - endogenous 33 amino acid peptide that is released into bloodstream during meals
*Causes reduction in appetite and satiation
*Suppresses weight gain
-Bombesin - peptide found to reduce food intake in rats
-Corticotropin-Releasing Hormone (CRH) - 41 amino acid peptide produced in the paraventricular hypothalamus and other regions of brain that reduces food intake
-Serotonin (5HT) - neurotransmitter which decreases food intake.
What are the neural control of cognitive factors?
-Thinking about food makes us hungry
-Images, memories, sights and smells
-Amygdala and inferior frontal cortex
What is the role of inferior frontal cortex?
-Receives messages from the olfactory bulb (smell area of brain).
-As odours influence the taste of foods - damage to this area should decrease eating - in response to smell and taste. (Kolb and Whishaw 2006).
What is the role of amygdala?
-Removal of the amygdala in rats leads them to eat both familiar and unfamiliar food with the same interest—rats will be careful about unfamiliar food with their amygdala intact.
-Patients with Kluver-Bucy syndrome have damage to both their amygdala & inferior prefrontal cortex. People with this syndrome show indiscriminate eating behaviour, even to the extent that sometimes they will try to eat non-food items.
What are some strenghts of neural mechanisms and eating behaviour?
+Reflection on people's experience of hunger\satiety
+Insight into brain chemicals - could be used to develop medical interventions to help change what we eat
+Provides explanation of some differences in eating behaviour
+Studies such as those involving lesions to the LH and VMH in rats have supported the role of the hypothalamus in regulating eating behaviour
+Studies involving electrical stimulation of these centres have confirmed their role in feeding and satiety.
+Such studies provide sound scientific evidence but there is the issue of extrapolating finding from rats to humans.
+Research evidence
*Cumming et al, 2004 - ghrelin
What are some limitations of neural mechanisms and eating behaviour?
-Reductionism: focus exclusively on biological aspects of hunger and satiety
-Biological determinism: focus exclusively on the role of nature and no space left to choice and cultural and social influences
-there is substantial and convincing evidence that social, cultural and psychological factors affect our eating behaviours as is evident from psychological explanations of eating disorders
-Use of animals in research implies lack of generalisability
-Highly controlled lab experiments may lack ecological validity
-Physiological drives can be overridden (e.g. desire to loose weight; dislike of certain foods; fear of losing control; social cues to continue eating; food availability)
What is an evaluation of the biological explanation?
-Theory focuses only on nature ignoring nurture thus factors such as cultural influences. Therefore its a determinist approach suggesting eating is due to neural mechanisms not free will.
-May be a strength as obese individuals/parents wont be guilty of causing it thus wont experience psychological harm.
-Also suggests treatments can be found.
-It does take into account cognitive, evolutionary and biological factors so can't be described as reductionist which is a strength.
-Mostly relies on animal studies & observations on them.
-Extrapolation>ethics. It's research is scientific as its objective, empirical and replicable.
What is a real world application to challenge Marie's study?
Research has indicated that neuropeptide Y, found in the lateral hypothalmus, has an important role in eating behaviour. This suggests that one of the main reasons why overweight people continue to eat too much is because the brain prodces NPY in exessive amounts, telling the individual that they are constantly hungry. However, recent research in Canada (Yang), has shown that NPY is also produced by abdominal fat. The researchers suggested that this leads to a vicious cycle where NPY produced in the brain leads to mroe eating and the production of more fat cells and so on. By targeting individuals at risk of increased levels of NPY, Yang believed it should be possible to treat them with drugs that turn off NPY and thus preveny obesity.
What is the optimal foraging theory from the evolutionary explanation of food preference?
-MacArthur and Pianka
-The Environment of Evolutionary Adaption refers to the original environment in which humans developed (the African Savannah), so natural selection favoured behaviours which were adaptive for that environment. As animals evolve, they tend to get bigger, but this increase in size requires increased calorie intake, so adaptions must occur in order for growth to happen. One strategy is to increase the amount of food eaten, but most primates cannot deal with high plant diets so chimps and humans evolved to eat a more mixed diet. This also increases the range of environments in which they can live. Humans were organised in hunter gatherer societies and would have eaten what was in that environment. Therefore, this all suggests that the preference for savoury foods can be traced back to our environment of evolutionary adaption.
What is the importance of meat and calories in our diets according to the optimal foraging theory?
-It is said that animals aim to increase calorie intake whilst spending the least time and effort doing so. Two million years ago forest began to decline, so evolutionary theory says that this accounts for the shift to meat eating, especially liver, kidneys and brain, which is high in fat, calories and nutrients. Preferences for fatty foods would also have evolved because they are a rich source of calories and nutrients.
-Meat is high in protein and energy-rich fat. Group hunting skills made it more available and cooking more palatable. Meat is also associated with a growth in human intelligence. Meat hunting was risky and dangerous. Meat can be toxic and incur transmittable diseases.
What did Milton say about the importance of meat and calories in our diets according to the optimal foraging theory?
-Theorised that this meat diet facilitated development of the brain which would not have been possible on low-calorie plant diet.
Whose theory links to Milton's?
-Cartwright also links the development of the human brain 2 million years ago to changes in diet, but also says that organisation into hunter-gatherers required a larger brain for social and communication purposes.
What research evidence is there for the importance of meat and calories in our diets according to the optimal foraging theory?
-Finch and Standford: Believed that humans adapted to eat diverse foods including meat, as it allows them to exploit new environments, suggesting an adaptive advantage to meat eating.
-Foley and Lee: also compared the brain size with primate feeding strategies and concluded that meat eating led directly to the process of encephalisation, suggesting that evolution meat eating in humans.
Where does some evideence for the optimal foraging theory come from?
-Hawkes: Studied the Ache tribe in the Amazonian rainforest, who are hunter-gatherers. He observed that the hunters balance the tiem spent hunting prey with the returns that prey brings. Meat makes up 45% of the diet, with plants the rest. He explains this as a risk reduction strategy - hunting has a high failure rate so there must be a second food source.
-Also found that there was no relationship between the contribution made by an individual to the size of the kill and the share they got from it. Instead food was used to secure alliances, to enhance status and therefore to gain sexual advantage and used to secure alliances, to enhance status and therefore to gain sexual advantage and increase reproductive success. The females in the tribe preferred the best hunters as mates.
What did Gibson and Wardle aim to explore?
-Aimed to explore calorie density in food choice. They offered children choices and foind that bananas and potatoes were preferred by 4-5 year olds over sweet flavour alone and protein content.
What did Abrams do?
-Demonstrated that all societies display a preference for animal foods and fats. This suggests that as the preference is universal, this is an evolutionary adaption.
What did Buss do?
-Reports that in some modern hunter gatherer societies women will divorce men who do not provide food.
What are some evaluating points for the optimal foraging theory?
-Kendrick found that longevity is associated with vegetarianism, suggesting that there is a cost to meat eating.
-Dunn points out that our dental structures and digestive systems are more similar to herbivores than carnivores and that true carnivores eat meat raw, guts and all suggesting we do not have an innate preference for meat.
-The American Academy of Peadiatrics point out that neonates can only ingest milk; meat is a late introduction to our diet and neophobics tend to dislike meat. This does not suggest an evolutionary determined preference for meat eating.
How does a preference for cooked food link with the evolutionary explanation?
-Cooking may be adaptive in that it makes food more edible and therefore makes food more easily digested, using fewer calories on the actual digestive process. It also reduces wear and tear on teeth.
-Wobber demonstrated that great apes preferred meat, sweet potatoes and carrots if they were cooked than raw, but no preference between cooked and raw apples and ordinary potatoes. This preference was shown even with foods they had not eaten before.
-Chimps have also been shown to prefer seeds that have been cooked over a fire than raw seeds (Brewer).
How does preference for sweetness link with the evolutionary explanation?
-This could have evolved for 2 reasons:
*Sweet substances are high in calories, so a sweet taste would indicate a ready source of energy.
*Sweet substances are rarely poisonous, so a sweet taste would indicate a safe food.
-Individuals with a preference for sweet tastes would be more likely to survive, reproduce and pass on genes.
What did Steiner do towards the preference for sweetness?
-Used choice preferences and facial expressions to conclude that neonates show preference for sweet flavours and rejection/disgust to bitter tastes. Breast milk is sweet, which will ensure that it is ingested readily by a baby which will then be more likely to survive.
What is a limitationn of Steiners study?
-Interpreting new born behaviour is difficult and prone to biases.
-Beauchamp found that dietary experience modifies preference for sweetness by as early as 6 months of age.
What is some further evidence for the preference for sweetness?
-Glucose is necessary for brain and body function, excessive glucose is stored as fat for when fatty foods are not available.
*Desor suggests that even 1-3 day old infants prefered sweet flavours.
*Grill and Norgren showed rats in the lab immediately accept foods that are sweet and conclude that the response is almost reflex-like.
*Belle showed that cultures such as the Inuit of Northern Alaska, who have traditionally lacked sweet foods in their diet when they come into contact with cultures that do eat them, even though they themselves have little or no experience.
-Evidence from biology that we are sensitive to swerrt than any other flavour sensation.
-Sugar is an extremely valuable substance that helps us survive. It provides us with fast and effective energy, and it supplies our brains with the fuel to make good and effective decisions quickly. Those with these advantages are more likely to survive than those without.
What is an evaluation of the preference of sweetness and the evolutionary explanation?
-A fondness for sweetness is common in the animal kingdom, lending support to an evolutionary preference.
-Stefansson reported that Copper Eskimos were disgusted at their first taste of sugar. This goes against the notion of sweetness being a universal preference.
-Zhao found a genetic basis to sweetness preference and believe that variations in the preference can be explained by the variability of the genes in individuals rather than cultural differences.
What is the adaptive advantage of taste aversion - avoidind specific foods (Evolutionary Explanation)?
-In order to survive, all organisms must only ingest safe substances. We use sight, smell and taste of food and drink to assess whether it is safe to eat. Our stomach deal with some but not all harmful substances through hydrochloric acid. If a food makes us ill, we develop an aversion to it.
What is some research support of the adaptive advantage of taste aversion?
-Garcia studied taste aversion int he lab using saccharin flavoured water. They found that rats more easily learned to avoid drinking flavoured water when licking was followed by illness than by electric shock, and they more easily learned to avoid drinking water accompanied by clicks and light flashed when that drinking was followed by electric shock than by illness. They concluded that it was easier for rats to associate tastes with illness.
How does adaptive advantage of taste aversion fit with the evolutionary explanation?
-Animals with taste aversion learning ar emore liekly to survive and avoid illness-causin foods. Evolutionary psychologists have suggestsed that the rules governing taste aversion learning have been shaped by evolution (Bolles).
What are the applications and implications of the adaptive advantage of taste aversion?
-This has been used to help people suffering from cancer cope with taste aversion post-chemotherapy and radiotherapy as the therapy can cause gastrointestinal illness. As when Berstein and Webster gave patients a novel (unfamiliar) tasting ice-cream prior to their treatment, they developed an aversion to the ice-cream. This then made it easier for doctors to aid in patients recovery as giving a novel food pre-treatment led to new food being rejected, not normal diet. In this way, patients were helped to maintain their nutritional status, which is crucial for healing. This is consistent with an adaptive aboidance of novel foods known as neophobia.
What are some evaluating points of the evolutionary explanation?
-Seligman: used the term 'biological preparedness' to refer to the innate (inherited) predisposing behaviours which assist survival. These can include aversion and the nedicine effect.
-Ignores the role of society, parenting and experience and therefore a reductionist explanation.
-Fossil evidence (teeth, digestive system) provide evidence of the shift to meat eating and hunter gatherer societies.
-Can explain unusual food preferences including sickness
-Nature rather than nurture
-Use of animals in research: we do show similarities to other species - chimps close to humans so studying their food preferences and behaviour can lead to generalising findings.
What are the four main psychological characteristics of anorexia nervosa?
-Behavioural symptoms - Weight is less than 85% of expected
-Cognitive symptoms - Distorted self perception of body shape & overemphasis of its importance for self-esteem
-Emotional symptoms - Intense fear of gaining weight
-Somatic symptoms - Absence of menstruation (amenorrhoea) for 3 months
What is a prevalance of anorexia nervosa?
-Affects 1 in 200 adolescents
-90% of sufferers are female
-Most common in 15-17 year old girls
What is a prognosis of anorexia nervosa?
-8% die within 5 years of onset
-70% recover within 10 years
-22% struggle with chronic symptoms
What is the cognitive explanation?
-The result of Faulty or Maladaptive Thought Processes about the Self, the Body and Food/Eating:
*Misperceiving the body as overweight when it is actually underweight
*Basing feelings of self worth unduly on physical appearance
*Basing sense of self on how they can control their eating/ED symptoms
*Irrational/mistaken beliefs about food/fat/dieting behaviours
What are some of the cognitive errors in EDs?
-All or nothing thinking
-Magical thinking
What are some initial point of cognitive errors in EDs?
-Women are generally more dissatisfied than men with their bodies.
-ED patients misperceive their own bodies and have more unrealistic body idealss.
-In ED patients, minor events related to eating activate fear of weight gain.
What did Fallon and Rozin do?
-Demonstrated that both men and women have distorted beliefs about body size. They surveyed males and females without eating disorders and founf that females rated their ideal body weight as lower than the weight males thought most attractive, and males rated their body weight as higher than most females found attractive.
What is some research support for cognitive errors?
-Garner and Bemis identify a number of cognitive errors which underlie and influence behaviour of anorexics:
*Selective abstraction: selecting small parts of a situation and coming to conclusions on this basis.
*Dichotomous reasoning: thinking in terms of extremes
*Magnification: exaggerating the importance of events - gaining a pound will push me over the brink.
-Conclusions drawn from this type of thinking are never questioned and therefore maintain the disorder. The anorexic becomes increasingly isolated with their cognitions which make sense to them.
What did McKenzie show into cognitive errors in EDs?
-Female ED patients overestimated their own body size in relation to other women.
-They judged their ideal weight to be lower than comparable non-ED patients.
-Following a sugary snack, they judged their body size to have increased. Controls did not.
What is some other research support to the cognitive errors in EDs?
-Cooper:A number of studies also indicate that people with eating disorders experience disturbances in information processing with regard to food and eating, weight and body shape stimuli. The use of a modified Stroop procedure has revealed attentional biases in individuals with anorexia nervosa and bulimia nervosa, with greater attention given to words related to food, weight and body shape.
What is a conclusion to cognitive errors in eating disorders?
-AN and BN are certainly associated with biases and distortions in thinking
-However, most women are dissatisfied with their bodies, not all of them develop Eds
-A good account of what helps to maintain EDS, but not of what causes them in the first place.
What is the behavioural explanations of eating disorders?
-Psychological disorders are the result of abnormal learning experiences.
-Eating disorders are a set of learned emotional and behavioural responses to food, eating and the body.
How does classical and operant conditioning fit in with the behavioural explanation of anorexia nervosa?
-Classical conditiong: learning through association
*A learned association between eating and anxiety-losing weight ensures the individual reduces these feelings of anxiety.
-Operant conditioning: learning through rewards and punishment
*Reinforcement of dieting/weight loss behaviours
(Compliments from others, avoidance of bullying)
How does the social learning theory link with anorexia nervosa?
-Social learning-learning through imitation and modeling:
*Observation of slim models being admired/successful (vicarious reinforcement)
*Observation of overweight people being punished
*Tendency to imitate in order to obtain same reinforcers and/or avoid same punishments
How can the media link with the social learning theory and eating disorders?
-The media are a major source of influence for the body image attitudes maintained by Western adolescents. For example, the portrayal of thin models on television and in magazines is a significant contributory factor in body image concerns and the drive for thinness among Western adolescent girls. The media does not inluence everyone in the same way, for example individuals with low self-esteem are more likely to compare themselves to idealised images portrayed in the media (Jones and Buckingham).
What is some evaluating points of the media and eating disorders?
-Evidence for the role of the media in shaping perceptions of body image comes from studies of societies where television has been introduced. Eating attitudes and behaviours were studied among adolescent Fijian girls following the introduction of television in 1995 (Becker). The girls stated a desire to lose weight to become more like Western television characters. However, other research has shown that instructional intervention prior to media exposure to idealised female images prevents the adverse effects of exposure (Yamamiya).
What is the evidence for the behavioural explanation?
-Barlow & Durand (1995) found that over half of contestants in the 'Miss America' contest were 15% or more below the expected body weight for their height.
-Fearn (1999) studied young women living on the island of Fiji. Before 1995, Fiji did not receive Western TV channels, they were introduced in 1995. by 1998, 74% of young Fijian women surveyed said they were "too big or fat", and eating disorders, previously unknown on the island, had begun to appear.
-Eysenck & Flanagan (2000) point out that, whilst virtually all young women in the West are exposed to the media, only 3-4% of them develop an eating disorder.
What is the psychodynamic explanation?
-Psychological disorders are a manifestation of repressed emotional problems
-The symptoms of eating disorders symbolise repressed conflicts and motives in the unconscious mind
What did Bruch do?
-Ineffective Parenting
*Effective parents respond appropriately to their child's needs (e.g. feeding them when hungry) and Ineffective parents who fail to respond to these needs.
*E.g. if a child cries because they are anxious, an ineffective parent might feed them or comfort them when they are hungry.
*During adolescence, they want autonomy but may feel they do not own their bodies and to overcome their helplessness will take excessive control over their body shape & size.
What was Bruch's psychodynamic explanation?
-Bruch's theory is supported by observations that parents of adolescents with AN have a tendency to define their own (Steiner). Bruch found that many of these parents claimed to 'anticipate' their children's needs rather than ever letting them 'feel' hungry (Bruch). Research also supports Bruch's claim that AN rely excessively on the opinions of others, worry about how others view them and feel a lack of control over their lives (Button and Warren).
What was Bruch's full study?
Aim - to explore family systems in relation to explaining anorexia nervosa.
Procedure- Interviewed parents of 51 anorexic girls.
• parents tended to be: financially well off, achievement-oriented, placing pressure on daughter to succeed. Saw daughter not as a person in her own right but as someone who could make their lives more satisfying and complete.
• Girls were mostly high achievers but excelled to please others not themselves.
• Girls had little sense of autonomy or who they were and little control over their own lives. Parents anticipated child's needs rather than ever letting them experience need.
Adolescence brings increasing pressure for autonomy and independence, plus bodily changes which are outside the individual's control. This leads to increasing feelings of helplessness and lack of control, so to overcome these feelings they seek control over their own body and food intake.
Bruch (1979) says that anorexia is associated with psychosexual maturity in several ways:
1. Fantasy of oral impregnation and confusion of fatness with pregnancy, then unconsciously believe that eating will lead to pregnancy so starve themselves.
2. Or eating is associated with taking on an adult sexual role so starve themselves in order to remain children or to regress to childhood.
3. Mutual reward between mothers and daughters in that mother retains her child, daughter secures dependency.
What is an evaluation of Bruch's study?
-Method can be criticised for sample selection - was it biased because of Bruch's own case load and perspective? However, strong ecological validity because used interviews and in-depth analysis. Theory can be generated form this. Retrospective.
-Additional support comes from Button & Warren (2001) who found that people with AN rely excessively on the opinions of others, worry about how others see them and feel a lack of control over their lives.
What is Minuchin's family systems theory?
This theory and explanation is based on case notes, observation, analysis and reflection of own case load.
Sees anorexia as attempt to prevent dissension within the family by drawing attention to oneself. Anorexia is a response to relationships within dysfunctional families. Such families have the following characteristics:
1. Enmeshment - family members are bound together in a tight and constricting network. Insistence on 'togetherness' swamps the young person who loses their sense of identity and self control.
2. Over-protectiveness - family members show extreme concern for each others' well-being
3. Rigidity - there is pressure to keep things the way they are rather than to adapt to new situations such as adolescence
4. Conflict - family relationships tend to be in a state of constant conflict. This conflict is usually denied, covered up and unresolved.
Adolescence threatens the fragile stability of such families and parent place pressure on the young person to adopt a 'sick role' in order to return them to the bosom of the family. Anorexia is one such solution - parents protect the anorexic, worry about her, show concern. Anorexic deflects attention away from the conflicts underlying family relationships.
What is an evaluation of Minuchin's family systems theory?
-Some family relationships may be the result of, not the cause of, a member having anorexia.
-Not consistently substantiated by other research.
-Sample bias?
-Sample size small.
What did Wonderlich do?
-Survey of 1099 American women
*sexual experiences during childhood
*eating disorder symptoms
-Women with a history of sexual abuse had elevated risk of ED symptoms
-Some issues surrounding retrospective data, but has been confirmed in other studies.
What are some general criticisms?
-Some support, mainly from studies of women abused in childhood
-However, not all abuse survivors develop EDs, and not all ED sufferers have been abused
-Many aspects difficult to test e.g. unconscious motives, repressed memories etc.
How can the diathesis stress model be used to evaluate the psychodynamich explanation?
-This can help us understand the development of eating disorders from a psychological perspective. Individuals might already have the genetic predisposition (biological vulnerability) to develop the disorder. Therefore, some kind of psychological factor e.g. early traumatic experience, personality traits or particular cognitive schemata could trigger the behaviour. Hence, once a disorder has developed, any psychological explanation for that disorder needs to account for the factors that help to maintain it.
What did Becker do into Media explanations of eating disorders?
Eating behaviours and attitudes following prolonged exposure to television among ethnic Fijian adolescent girls
Aim - to evaluate the impact of the recent introduction of Western television on disordered eating among ethnic (indigenous) Fijian adolescent girls.
Procedure - a naturalistic experiment. These girls were not accustomed to much (if any) TV and disordered eating was rare among this group (only one documented case of AN by 1995).
2 separate samples of girls aged 16-17 were assessed using questionnaires and interviews to obtain quantitative and qualitative data. First assessment (N = 63) was 1995, within a few weeks of the introduction of TV to the area, second assessment (N = 65) 3 years later. The EAT 26 questionnaire includes questions about body image, bingeing and purging behaviours. A score of 20 or more is high. Questions were also asked about hours of TV viewing and height & weight were measured.
• Significant increase in the prevalence of 2 key indicators of disordered eating (high EAT26 score and self induced vomiting to lose weight following prolonged exposure to TV). This suggests that TV has a profound impact, particularly as eating attitudes and behaviours were traditionally so different.
• Feeling too big or fat was significantly associated with current dieting, suggesting that body dissatisfaction is related to behavioural changes.
• Exposure to idealised images of beauty in the media stimulates social comparison and potential body image disturbance or dissatisfaction.
What are some strengths to Becker's study?
-Naturalistic experiment.
-Unique because populations without TV exposure are so rare.
-Looked at qualitative data
What are some limitations to Becker's study?
-Clinical diagnoses were not sought, so disordered eating attitudes and behaviours do not equate with eating disorder (although high EAT and induced vomiting are associated with eating disorders)
-Small samples, but these were comparable and high levels of significance were found.
What is an overall evaluation of Becker's study?
-Study provides new support (because naturalistic and qualitative) for the impact of TV (a cultural/environmental artefact) on the causes of disordered eating.
-Challenged by Yamamiya (2005) instructional intervention prior to media exposure to idealised female images prevents the adverse effects of exposure.
What was the APFC of Holland's study of genetic vulnerability in anorexics?
-Aim:A variety of data suggest that Anorexia may have a genetic basis. This study aimed to explore this possibility by comparing incidence of anorexia in identical (MZ) and non-identical (DZ) twins. Since twins are raised in the same environment, similarity may be due to nature or nurture. However, if MZ twins are more similar, this implies that genes play a greater role.
*45 pairs of female twins were interviewed where at least one twin had had anorexia.
*The interviews established the clinical characteristics observed as well as the occurrence of eating disorders in any close relatives.
*Records were also made of body mass and length of amenorrhoea, and questions asked about drive to be thin and body dissatisfaction.
*In order to determine whether twins were identical or not, a blood test was used.
*There were 25 MZ twins and 20 DZ twins in the study.
-Findings:There was significantly higher concordance in the MZ twins; 25 (56%) of the MZ twins were concordant for anorexia whereas only 1 (5%) of the DZ twins was.
There was significantly more anorexia in relatives studied than found in the normal population. The rate of anorexia in the population in general is 0.1%. The study found 6 cases of anorexia among first-degree relatives (4.9%) and in the second-degree relatives there were 2 cases (1.2%).
The measures of body mass, amenorrhoea, drive to be thin and body dissatisfaction indicated that these were heritable as there was greater similarity between MZ and DZ twins.
-Conclusions:The findings from all three different methods of analysis suggest that anorexia has a large genetic component. The figure of heritability may be as large as 80%; in other words, 80% of the variation in anorexia is due to genetic factors and 20% to environmental factors. This high figure may be partly explained in terms of how genetic factors interact with the environment. What is inherited is a genetic sensitivity to environmental factors.
What are some strengths of Hollander's study?
-Many measurements were used for anlaysis in this study such as blood tests, body mass and clinical interviews. why this is a strength in this study, considering the type of data collected
-A more recent study by Bulik et al (2000) concluded that anorexia is 56% genetic, supporting Holland's suggestion that there is a strong genetic
What are some limitations of Hollander's study?
-One difficulty with studies of anorexia is that the actual diagnosis in any individual is not that certain. Some individuals suffer both anorexia and bulimia, though not always at the same time. This means that the genetic susceptibility may be to 'develop eating disorders' rather than anorexia in particular. Gorwood et al (1988) suggest that if we want to identify the genetic causes of anorexia, we need to identify the distinct subtypes more clearly.
-Twins don't just share the same genes - they also share cultural and family values, and the environment for MZ twins is more similar than for DZ twins. Therefore, physiological and environmental factors are confounded. Indeed, the 56% concordance rate in MZs might be entirely due to their more similar upbringing than DZs.
However, Holland et al argue that MZ twins who actually look very different still have the same high concordance rates as MZ twins who look identical.
-Small sample - many twin studies involve a small sample size. Holland et al studied only 25 MZ and 20 DZ twins, and it is estimated that 15,000 pairs would be needed for a definitive, genetic study. The low occurrence of both twin births and eating disorders make this unlikely.
-McClelland & Crisp (2001) found a higher incidence of AN in social classes 1 and 2. They reject the idea that this is due to higher referral levels and suggest it's due to an avoidance response to adolescent conflict within such families. Why does this challenge the findings of Holland et al?
-There may be reasons why twins are more prone to mental illness than non-twins and therefore the findings may not be generalisable to the rest of the population. It is possible that twins may be subject to greater developmental difficulties (e.g. sense of identity) - or that they are genetically more vulnerable than other adolescents.
-Why can't the study fully explain anorexia in terms of genetics? Additionally, can the study explain the dramatic increase of cases of AN in the last 30 years?
What is the 'adapted to flee' hypothesis innthe evolutionary explanation?
-Proposes that the typical AN symptoms of food restriction, hyperactivity and denial of starvation, reflect the operation of adaptive mechanisms that once caused migration in response to local famine conditions. Normally, when a person begins to lose weight, physiology mechanisms conserve energy and increase desire for food. These adaptions facilitate survival in hard times. However, among ancestral nomadic foragers, when extreme weight loss was due to a severe depletion of local food resources, this adaption must be turned off so that individuals can increase their chances of survival by migrating to a more favourable environment. Food restriction is a common feature of many species when feeding competes with other activities such as migration or breeding. During the Middle Ages, the phenomenon of 'holy anorexia' was widespread among pious women. The hyperactivity typically found in anorexics may be a form of 'migratory restlessness' as many species increase activity in times of food shortage and prior to migration. In the EEA those starving foragers who deceived themselves about their physical condition would have been more confident about moving on to a more favourable (in terms of food availability) environment, and so would have been more likely to survive. Therefore, for modern-day individuals, among those who are genetically vulnerable to AN, losing too much weight may trigger these ancestral mechanisms.
What are some treatment implications of the 'adapted to flee' hypothesis?
-Guisinger claims that the AFHH 'relieves therapists of the need to search for familial reasons for AN'. A struggle for control between those with AN and those who want them to get better, is an often reported characteristic of AN. This struggle is explained in terms of the 'worried and uncomprehending family' on the one hand, and the anorexic's powerful biological urge to avoid food and to exercise. Awareness of this causal influence can help treatment, and encourage parents to be more compassionate toward an anorexic child.
What implications has the evolutionary explanations led to?
-Biological explanations of AN offer the promise of a range of treatment possibilities, including drug therapies to normalise neurotransmitter levels and even gene-replacement therapy. Bulik suggests that if we could use an individual's genetic profile to indicate level of risk, it would be possible to develop specially tailored prevention programmes for those most susceptible to developing AN. An additional advantage of treatments linked to biological explanations is that people then realise they are dealing with a dysfunctional biology (which is treatable) rather than a dysfunctional family (which often is not). Perhaps the most important implication of this is that it reduces the guilt generated by the view that it is parents who cause the development of eating disorders in their children.
What is the reproductive suppresion hypothesis of the evolutionary explanation?
-Surbey: suggests that adolescent girls' desire to control their weight represents an evolutionary adaption in which ancestral girls delayed the onset of sexual maturation in response to cues about the probability of poor reproductive success. The ability to delay reproduction is adaptive because it enables a female to avoid giving birth at a time when conditions are not conductive to her offspring's survival. This model is based on the observation that in a number of species puberty is delayed or reproduction suppressed in females when they are subjected to stress or are in poor physical condition. Surbey argues that AN is a 'disorder variant' of the adaptive ability of females to alter the timing of reproduction at a time when they feel unable to cope with the biological, emotional and social responsibilities of womanhood.
What are some problems associated with evolutionary explanations?
-We might question how the symptoms of AN might be passed only natural selection, particularly as they decrease fertility and could even kill the individual with this condition. AN would have functioned more effectively in ancestral conditions, yet outside the ecological setting in which it evolved disorders such as AN can be deadly.
What are some criticisms with the evolutionary explanation?
-This hypotheses is supported by the observation that menarche (the onset of puberty) is delayed in prepubertal girls with AN. Additionally, since amenorrhoea is a typical characteristic of AN, this means that reproduction is effectively suspended in anorexic females.
-Reductionist: not search for more complex explanation, such as the emotional relationships within families as a cause
-Deterministic: view that an individual's behaviour is shaped/controlled by internal forces rather than an individual's will to do something
-Cultural Influence: doesn't acknowledge the importance of cultural influences, e.g. if it is adaptive & innate then why doesn't it happen in all cultures?
How do neurotransmitters (serotonin) of anorexia nervosa fit with teh neural explanation?
-Disturbances in levels of the neurotransmitter serotonin appear to be a characteristic of individuals with eating disorders. Bailer compared serotonin activity in women recovering from restricting-type anorexia and binge-eating/purging type with healthy controls. They found significantly higher serotonin activity in the women recovering from the binge-eating/purging type. In addition they found the highest levels of serotonin activity in women who showed the most anxiety, suggesting that persistent disruption of serotonin levels may lead to increased anxiety, which may trigger AN.
What has been some research done into the neurotransmitters (dopamine)?
-Kaye used a PET scan to compare dopamine activity in the brains of 10 women recovering from AN, and 12 healthy women. In the AN women, they found over activity in dopamine receptors in a part of the brain known as the basal ganglia, where dopamine plays a part in the interpretation of harm and pleasure. Increased dopamine activity in this area appears to alter the way people interpret rewards. Individuals with AN find it difficult to associate good feelings with the things that most people find pleasurable (such as food).
What is the neurodevelopment (pregnancy and birth complications) of AN in the neural explanations?
-Lindberg and Hjern found a significant association between premature birth and development of AN. Birth complications may lead to brain damage caused by hypoxia (lack of oxygen), impairing the neurodevelopment of the child. Nutritional factors may be implicated if mothers have an eating disorder. Bulik suggest that mothers with AN expose their offspring to 'double disadvantage' - transmission of a genetic vulnerability to AN, and inadequate nutrition during pregnancy.
What was some neurodevelopment research (season of birth) part of neural explanations?
-Individuals with AN are more likely to have been born during the spring months. Explanations for this intriguing association include intrauterine infections during pregnancy and temperature at time of conception. For example, a study by Willoughby found that among patients with AN in equatorial regions of the world (where it is constantly hot), there was no seasonality effect in the development of AN.
What are some general criticisms of the neural explanations?
-Gender Bias: Most studies of eating disorders have concentrated on the study of women but, according to recent statistics, 25% of adults with eating disorders are men. Whether that figure indicates that more men nowadays suffer from disordered eating compared to ten years ago, or whether previously boys and men escaped attention, is not yet clear. However, what this does show is that eating disorders such as AN are not exclusively a female problem.
-Biological Determinism: An unlikely consequence of research in this area has been its implication for insurance pay-outs for psychiatric conditions. In the US, for example, treatment for AN is restricted under many insurance plans because it is not considered to be 'biologically based'. However, research such as that considered on the spread creates a case for insurance companies to consider AN in the same way as other psychiatric conditions (such as schizophrenia) that are considered to be biologically based.
Who did research into the cultural factors that influence attitudes to food?
-Ogden: food choice takes place within a network of social planning:
*Main factors - religion (fasting, lent) control eating behaviour based on their religion and beliefs.
*Groups play a role: can help form personal relations, used to show wealth
-Bandura: Important for social learning especially amongst children who copy parents eating habits.
-Birch: Adults and peers influence children to like foods they initially disliked.
-Lorenzen: media plays a role
*Men=watch adverts of fit, muscley men creates insecurities - majority of adverts shown in Western cultures.
-Feingold and Mazzella: Western cultures, since WW2 when food was rationed, "skinny" women are seen as "better".
-Akiba and Yang: People who don't live in Western culutres aren't affected as they are not exposed to these forms of media.
What was Lawrance's study?
-Method: Discussion groups were set up across the UK to explore factors that might affect the food choices of girls and young women of African and South Asian descent. The discussions were analysed using content analysis.
-Results: A number of common concerns were voiced by the women. Food choices were indeed influenced by culture, time, availability, cost, health and price.
*Pakistani/Bangladeshi women's cooking skills appeared to have been learnt from the older generation of females in the family, and they also took pride in their traditional cooking.
*All the women surveyed appeared to have low levels of western food in their diets. However, they appeared to adopt the less healthy aspects of the western diet including fried fish, pizza, chips and fatty snack foods. However, these were mainly chosen to give people a change or when preparation time available was short.
*The Pakistani/Bangladeshi women expressed the opinion that their diet had become less healthy following the adoption of the worst of the British diet!
*The women did make a link between food and health; however, cultural background and knowledge influenced this.
*Pakistani/Bangladeshi women generally appeared to have quite a good understanding of what food and methods of cooking are healthy and unhealthy. However, this knowledge did not appear to translate consistently into dietary choices.
*Zimbabwean women noted that in Zimbabwe nobody worried about being slim, but now that they were in the UK there was more pressure to be slim.
-Conclusion: many issues that affect the food choice of people who move to the UK are common within different ethnic groups.
What research has been done into the how healthy eating influences attitudes to food?
-People may be eating healthily to avoid the development of chronic diseases such as diabetes. They may also be avoiding certain foods due to allergies and negative experiences, such as food poisoning.
-Verplanken: It mat also be down to low self esteem
-Ogden: showed that people don't always stick to the ideal healthy eating expectations of 5 portions of fruit and veg a day.
-Hayes and Ross: Suggested healthy eating may come about from concern of appearance.
-Steptoe: concern increases more in ageing women than men.
-Steptoe and Wardle: Provide a possible explanation for this by suggesting that people may not eat fruit and veg as they do not supply sufficient energy levels, compared to other foods.
-Armitage: showed that when people are more aware of where they can get healthy food from and have commited to being healthier by saying they will, than they are more likely to eat healthily.
What did Westcombe and Wardle do into healthy eating influencing eating habits?
-Procedure: 36 participants aged 18-53 tasted and rated three different kinds of food: three cheeses, three yoghurts and three koerrtas, a tofu-based food. The fact content in each case was virtually identical, but one was labelled as 'higher;, one 'normal' and one 'lower' in fat content. They were asked to rate each on how pleasant they tasted and how likely they were to buy them. They were also asked to assess how influenced they were by health concerns.
-Results: Overall, foods labelled 'lower' were rated as slightly less pleasant. However, fot the youghurts, participants reported that they were more likely to buy the 'lower' fat ones. Participants who claimed to be more influenced by health concerns in their food choices rated the 'higher' foods as less pleasant. They were less likely to but the 'higher' labelled yoghurts and cheeses than those for whome this was less important.
What research was done into mood and stress?
-Davey: Significant increase/decrease appetite = signs of depression/mood disorders.
-Ogden: Low mood - overeat to mask their mood (masking hypothesis)
-Crosica and Spring: Supported carbo craving syndrome (increases serotonin and neurotransmitters when eating carbohydrates
-Connor and Armitage: Observed 2 hypotheseis:
*General Effect Hypothesis-effect of food in general
*Individual Differences Hypothesis-only effects certain people's eating patterns.
-Lazorus and Folkman: eating habits are linked with stress
What did Garg do?
-Low mood can often result in comfort eating, although occasionally it seems to have the opposite effect and can cause reduction of eating.
-Garg et al (2007) got participants to watch a funny film (Sweet Home Alabama) or a tear jerker (Love Story) whilst the researchers watched the participants choice of snacks; either popcorn or grapes. Those watching Love Story consumed a third more popcorn than the other group whilst those watching Sweet Home Alabama ate more grapes.
What did Oliver do?
-When stressed people are more likely to overeat