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 * Physiological aspects of obesity
 * Runs in families- having an obese parent results in 40% chance of becoming obese
 * Having two makes it 80%
 * Chances of thin parents having an overweight child is about 7%- Garn et al. 1981
 * Stunkard et al. 1990
 * Twin study
 * 83 pairs of identical twins reared apart.
 * Twins' BMI, genetic factors accounted for 66-70 of the variance in body weight.
 * Concluded that a strong genetic component in the development o obesity
 * Genetics played a greater role in slim twins.
 * Could be because of metabolism, could be because of amount of fat cells in individuals.
 * Evidence that genes determine individual weight gain.
 * Humans genetically programmed to eat all the time when food is available to store fat for when food is scarce. No longer applicable now that food is plentiful and people aren't as physically active.
 * Sociocultural aspects of obesity
 * Jeffery 2001
 * Caused by environmental factors
 * Lack of physical activity
 * Eating behaviour
 * Sedentary lifestyle- lack of physical activity.
 * Prentice and Jebb 1995
 * Changes in physical activity in a UK sample.
 * Positive correlation between increase in obesity, car ownership and television viewing.
 * Note- study was correlational. No cause-and-effect relationship actually found.
 * Lakdawalla and Philipson 2002
 * Economists
 * Estimated that 60% of total weight growth was because of a lack of physical activity, 40% due t increase in calorie intake.
 * Has been argued that overeating is causing obesity, ie in compulsive eating disorders, but generally research has not been able to support that overeating is the main reason for growth in obesity rates in the population.
 * UK national food survey
 * Since 1970 distinct increase in amount of food eaten (at home?)
 * Prentice and Jebb 1995- population data did ot show an obvious relationship between the increase in obesity and changes in food intake.
 * Suggested that obesity is 'an inevitable consequence of a society flooded with energy-dense, cheap foods, labour-saving devices, motorized transport and sedentary work.
 * Prentice and Jebb 1995
 * Change in what people eat
 * Calorie intake grw by 25% between 1973-1999 (US)
 * Fat proportion theory of obesity
 * The obese simply eat more fat.
 * Blunden et al 1997
 * High fat eaters 19 times more likely to be obese
 * Same findings for carbohydrate studies and others.
 * Chou et al 2004- wealthier and more educated individuals are less likely to have obesity problems compared to poorer others.
 * Cognitive factors relating to obesity
 * Cultural ideals. Body images, idealized perceptions which are different for different cultures/times (yawn)
 * West is individualistic, people responsible for own fate, suggested that those with slim body have 'control' and an obese one indicates the opposite.
 * Cognitive restraint theory
 * People replace physiological hunger sensations with 'cognitive restraint'
 * Suggests that dieting in itself could lead to obesity.
 * Many obese people are 'chronic dieters', most have broken diets.
 * Restraint theory- extreme cognitive restraint likely to ake an individual respond to external cues/emotional events with 'loss of control' and/or weight eating.
 * False hope syndrome
 * Polivy 2001
 * Obese dieters set unrealisitc goals and are ovely optimistic
 * Assume that weight loss will produce radical changes in their lives
 * Cocktail of false hopes and unattainable criteria for success could be explanation for lack of success
 * Many dieters have 'all or nothing' ways of thinking- 'what the hell' effect. If they think one transgression as ruined the overall effect then they probably won't only stop the diet but indulge in food.
 * Prevention strategies
 * Healthy eating
 * Balanced diet
 * Intake of 'macronutrients', 'nutrients'.
 * Public information campaigns, schemes….
 * Treatments
 * Blair-West 2007
 * Successful dieting should be based on knowledge from research- restraint theory, stages of change theory
 * Processes of change can be divided into five stages
 * Precontemplation
 * Contemplation
 * Preparation
 * Action
 * Maintenance
 * Blair-West created a treatment programme for Australia includeing:
 * Realistic goal-setting
 * Low-sacrifice diet
 * People should eat less but not necessarily give up the foods they love
 * Physical activity
 * Information