Eating behaviour Outlines
Outline the evolutionary explanation for food preferences (6 marks)
Preference for fatty food in EEA important for energy resources
Meat important for early humans as eating densely nutritious food leads to brain growth.
Preference for sweet foods:
i) Sweetness associated with high concentration and are readily available as calories.
ii) E.g., fruit= sweet= source of vitamins and minerals which are necessary for bodily
function and growth
iii) Mennella (2014) = children who preferred sweet solutions over salty ones tended to be
tall for their age
Taste aversion:
I. A learned response to avoid eating toxic, spoiled or poisonous food. Could also avoid
odour for food= avoid illness
II. Garcia (1955) = taste aversion on rats= rats who had been made ill through radiation
shortly after eating saccharin developed an aversion to it and quickly associated
their illness with saccharin
Neophobia:
I. Reluctance to consume new or unusual foods= survival mechanism to avoid illness
II. Martins (1997) = humans avoid animals’ products because it’s associated with a
greater risk of illness
III. Rozin (1976) = rats come neophobic of unfamiliar foods if they become ill when
eating familiar foods and unfamiliar foods
Outline the biological explanation to obesity (6 marks)
Genetic explanation
Looks at genetic influences of obesity risk have used twin studies and adoption.
Twin studies:
o Maes (1997) = meta-analysis 75000 people= heritability estimates for BMI of 74% in
MZ and DZ 32%
o Average 40-75%
Adoption studies:
o Allows researchers to look separately at influence of biological parents and adoptive
parents
o Stunkard (1986) = 540 adults’ adoptees= strong relationship between weight
categories of adopted people and biological parents’ weight BUT= no relationship
with adoptive parents’ weight= not 100% biological
Neural explanations
Thirty gene hypotheses:
o Neel (1962) = tendency to gorge on available food to prepare for periods of famine,
this would lead to increased body weight, so survival mechanism when we were in
EEA
o People with this gene have advantage, so would survive, stayed with us.
o People believe they are preparing for a famine that will never happen, so become
obese.
, Hypothalamus:
o Regulates metabolism, collects neurons monitors sugar levels in blood.
o Arcuate nucleus= responsible for obesity, monitors sugar levels in blood and acts
when energy is low= sends messages to other parts of body, producing desire to eat
o Responsible for maintenance of body weight= malfunction= obesity=overeating=
keep messages sent
Leptin:
o Inhibits food intake by acting on leptin receptors in appetite control centres in brain.
o Byers and Myers (2003) = showed disruption of leptin signalling in hypothalamus
results in obesity
Outline the cognitive approach explaining anorexia (6 marks)
Cognitive distortions= error in thinking:
o Believe they’re overweight.
o Could be due to comparisons with models in media.
o May be wrong as they are actually a normal weight or even underweight
Irrational beliefs:
o Not based on fact tend to be unrealistic.
o E.g., believe they must be thin to be loved by others.
o Or blame their weight for their social exclusion.
Cognitive Behaviour Model (Garner and Bemis 1982):
o Anorexia patients have many characteristics in common= typically perfectionistic
and are often full of self-doubt
o Characteristics and exposure to cultural ideas of thinness leads to form extreme
ideas about importance of people’s weight and irrational belief that losing weight
will reduce distress and make them more attractive
Transdiagnostic model (Fairburn 2003):
o Suggested we should see AN symptom as manifestations of a more broadly defined
eating disorder= set of cognitive distortions
o Parried with reduced capacity for set-shifting and overestimation of body weight and
appearance and emphasis on self-control= leads to AN
o AN maintained by enhanced self-esteem as a result of self-control; starvation
changes seen as failure of self-control, leading to more food restriction and
increased self-monitoring.
Outline the family systems theory as an explanation for anorexia (6 marks)
Minuchin (1978) Psychosomatic family model= prerequisite for development of AN was
dysfunctional family occurring alongside physiological vulnerability in the child
Enmeshment= families are over-involved, interdependent, no clear emotional boundaries,
inhibited sense of individuality
Autonomy= enmeshment families place constraints on its members, who are not allowed to
become independent and develop autonomy
Control= enmeshment families exert overprotective control over members. Adolescent
refuse by refusal to eat
rigidity of style= interactions are inflexible, denial of need to change
conflict avoidance=family members suppress conflict, differences of opinion/problems are
not discussed.
Triangulation — Involves a pair of family members either incorporating or rejecting a third
family member.
Outline the evolutionary explanation for food preferences (6 marks)
Preference for fatty food in EEA important for energy resources
Meat important for early humans as eating densely nutritious food leads to brain growth.
Preference for sweet foods:
i) Sweetness associated with high concentration and are readily available as calories.
ii) E.g., fruit= sweet= source of vitamins and minerals which are necessary for bodily
function and growth
iii) Mennella (2014) = children who preferred sweet solutions over salty ones tended to be
tall for their age
Taste aversion:
I. A learned response to avoid eating toxic, spoiled or poisonous food. Could also avoid
odour for food= avoid illness
II. Garcia (1955) = taste aversion on rats= rats who had been made ill through radiation
shortly after eating saccharin developed an aversion to it and quickly associated
their illness with saccharin
Neophobia:
I. Reluctance to consume new or unusual foods= survival mechanism to avoid illness
II. Martins (1997) = humans avoid animals’ products because it’s associated with a
greater risk of illness
III. Rozin (1976) = rats come neophobic of unfamiliar foods if they become ill when
eating familiar foods and unfamiliar foods
Outline the biological explanation to obesity (6 marks)
Genetic explanation
Looks at genetic influences of obesity risk have used twin studies and adoption.
Twin studies:
o Maes (1997) = meta-analysis 75000 people= heritability estimates for BMI of 74% in
MZ and DZ 32%
o Average 40-75%
Adoption studies:
o Allows researchers to look separately at influence of biological parents and adoptive
parents
o Stunkard (1986) = 540 adults’ adoptees= strong relationship between weight
categories of adopted people and biological parents’ weight BUT= no relationship
with adoptive parents’ weight= not 100% biological
Neural explanations
Thirty gene hypotheses:
o Neel (1962) = tendency to gorge on available food to prepare for periods of famine,
this would lead to increased body weight, so survival mechanism when we were in
EEA
o People with this gene have advantage, so would survive, stayed with us.
o People believe they are preparing for a famine that will never happen, so become
obese.
, Hypothalamus:
o Regulates metabolism, collects neurons monitors sugar levels in blood.
o Arcuate nucleus= responsible for obesity, monitors sugar levels in blood and acts
when energy is low= sends messages to other parts of body, producing desire to eat
o Responsible for maintenance of body weight= malfunction= obesity=overeating=
keep messages sent
Leptin:
o Inhibits food intake by acting on leptin receptors in appetite control centres in brain.
o Byers and Myers (2003) = showed disruption of leptin signalling in hypothalamus
results in obesity
Outline the cognitive approach explaining anorexia (6 marks)
Cognitive distortions= error in thinking:
o Believe they’re overweight.
o Could be due to comparisons with models in media.
o May be wrong as they are actually a normal weight or even underweight
Irrational beliefs:
o Not based on fact tend to be unrealistic.
o E.g., believe they must be thin to be loved by others.
o Or blame their weight for their social exclusion.
Cognitive Behaviour Model (Garner and Bemis 1982):
o Anorexia patients have many characteristics in common= typically perfectionistic
and are often full of self-doubt
o Characteristics and exposure to cultural ideas of thinness leads to form extreme
ideas about importance of people’s weight and irrational belief that losing weight
will reduce distress and make them more attractive
Transdiagnostic model (Fairburn 2003):
o Suggested we should see AN symptom as manifestations of a more broadly defined
eating disorder= set of cognitive distortions
o Parried with reduced capacity for set-shifting and overestimation of body weight and
appearance and emphasis on self-control= leads to AN
o AN maintained by enhanced self-esteem as a result of self-control; starvation
changes seen as failure of self-control, leading to more food restriction and
increased self-monitoring.
Outline the family systems theory as an explanation for anorexia (6 marks)
Minuchin (1978) Psychosomatic family model= prerequisite for development of AN was
dysfunctional family occurring alongside physiological vulnerability in the child
Enmeshment= families are over-involved, interdependent, no clear emotional boundaries,
inhibited sense of individuality
Autonomy= enmeshment families place constraints on its members, who are not allowed to
become independent and develop autonomy
Control= enmeshment families exert overprotective control over members. Adolescent
refuse by refusal to eat
rigidity of style= interactions are inflexible, denial of need to change
conflict avoidance=family members suppress conflict, differences of opinion/problems are
not discussed.
Triangulation — Involves a pair of family members either incorporating or rejecting a third
family member.
