Key words: under Anorexia Nervosa
Evolutionary explanation:
Food preferences - Palatability - Neophobia - Taste Aversions - Salt/Sweetness/Fat
Role of learning:
Classical and operant conditioning - Flavour-flavour Learning - Social Influences - Cultural
Influences -
Neutral and Hormonal mechanisms:
Hypothalamus - Ghrelin - Leptin - Genetic Explanations - Neural Explanations - Anorexia
Nervosa -
Family Systems Theory: - Autonomy - Control - Enmeshment - Overprotectiveness -
Rigidity - Conflict Avoidance -
Social Learning Theory: - Modelling - Reinforcement - Media -
Cognitive Theory: Cognitive Distortions - Irrational Beliefs -Set-shifting
Between half and two-thirds of men and women in 63 countries across five continents - not
including the US - were overweight or obese in 2006. The Circulation journal study included
over 168,000 people evaluated by a primary care doctor. Just 7% of people in eastern Asia
were obese, compared to 36% of people seeing their doctors in Canada, 38% of women in
Middle Eastern countries and 40% in South Africa.
A Foresight report released in the UK 2008 warned the government that it must act to stop
Britain "sleepwalking" into a crisis. The report, which was the largest UK study into obesity,
backed by the government and compiled by 250 experts, said excess weight had become
the norm in our "obesogenic" society. By 2050 90% of today's children will be overweight or
obese, it predicted.
Obesity in families:
BMI is measured in order to check the levels of obesity within a person. Concordance rates
are important to look at because it is prestigious to find findings in separating genetic and
environmental influences.. Therefore, concordance rates in first degree relatives are in the
region of 20-50%, indicating a moderate level of heritability ( Chaput et al)
Twin studies are used for a greater genetic component. Cassandra nan et al (2012)
conducted a meta-analysis of 12 twin studies involving over 8,000 MZ (monozygotic) and
nearly 10K on DZ (dizygotic) twins.> Concordance> 60%to 80%, demonstrating a
substantial genetic component to obesity remained influential from late childhood through
adolescence or adulthood
Polygenic Determination :Locke et al (2015) in a study of the genomes of 300,000 people,
identified 97 possible genes that relate to BMI alone. This is just one measure of obesity. It
is thought that those 97 genes only account for 3% of the genetic variation in BMI.
Potentially there are thousands involved in obesity in general. Polygenic = Includes multiple
genes, cannot be explained with one
Evaluation: