It’s estimated at any 1 time 40% of the female population is trying to lose weight, usually by dieting. If you are obese, losing weight has many health benefits. But many females diet when they have faulty perceptions of their actual body or are simply dissatisfied with their bodies. Ogden (’07) suggests some factors: Media Influence, Family, Ethnicity, Social Class, Peer groups & social learning. Why doesn’t dieting work? Some women can lose and maintain weight using diet only.
However, most can’t and bizarrely they end up eating more. Boundary model; Normal circumstances- Body weight set point controlled through homeostatic mechanisms, can’t fluctuate too much (PHYSIOLOGICAL BOUNDARY). But in restrained eaters person also has a COGNITIVE lower than PHYSIOLOGICAL. Tested using Preload/taste test. Non-dieters eat until they’re full; physiological. Dieters eat until cognitive reached; if high calorie preload disinhibits eating behaviour so eat until satiety.
Ogden ‘what the hell’ Herman and Mack: 3 conditions: 1st group no preload, 2nd group 1 milkshake, 3rd group 2 milkshakes – 2 & 3 asked to rate quality of the milkshakes then all given 3 flvours of ice cream given 10 mins to rate taste, told eat as much as they want. All pps given questionnaire to assess degree of dieting. All groups put into subgroups according to dieters and non-dieters. Found non-dieters at less in the 2 milkshakes conditions; understandable as would be fuller.
BUT surprisingly dieters ate significantly more in the 1 and 2 milkshakes condition than 0. Also the more they were trying to diet, the more they ate after the 2 milkshake preload. Concluded this supports a boundary model for food intake, the cognitive boundary; once overcome (preload) the ‘what the hell’ effect takes place so eat more in preload condition. Powell et al suggest dieting successful if combined with lifestyle changes e. g. PE, group/individual support and self monitoring(diary monitor progress- feel increased control)
Set realistic goals which can actually be maintained and good for health – Powell et al Psychology/physiology of dieting explains failures of dieting but also helped develop psychological and medical intervention to help weight loss. * Pharmalogical treatments: Treatment of Obesity, significant weight loss but side effects. Never recommended for long term as they don’t deal with psychological aspect and could be dangerous side effects. Orlistat- Stops absorption and processing of fat so it’s excreted Side effects e. g. oily faeces.
Sibutramine- acts on brain serotonin pathways which regulate food intake. SE e. g. High BP. * Surgical Treatment effective as stomach factors e. g. ghrelin in eating avoided and appetite reduced. Only used if obesity is life threatening as dangers of surgery and SE e. g. abscesses and lung infections also mortality rate 2-4% : Gastric band- around stomach reducing size hence amount of food eaten to feel full, Gastric Bypass- tube b/w duondeum and stomach again reduce stomach size so only small meals can be eaten.