Dieting - Studies

Herman and Mack (1975)

Procedure
- 15 participants in three conditions.
- No preload; one milkshake; two milkshakes.
- Groups 2 and 3 asked to rate the taste qualities of milkshake.
- All participants given 3 tubs of ice cream and 10 minutes to rate the tastes of them.
- Told they could eat as much as they'd like.
- All given a questionnaire on their degree of dietary restraint.

Findings
- Low-restraint participants ate less ice cream in the two milkshake condition than the one or zero (considered to be 'fuller')
- High restraint participants ate more ice cream in the one and two conditions than the zero condition.
- Significant positive correlation across all participants between score on eating restraint questionnaire and amount eaten after two preloads - higher restraint = more eaten.

Wegner et al (1987)

- Asked some participants not to think about a white bear.
- Ring a bell when thinking of bear.
- Told others to think about bear.
- Participants told not to think about bear rang bell more.

Thomas and Stern (1995) 

- Modest payments as a reward for weight loss do not enhance initial weight loss.
- Strategies to improve social networks have focused on teaching spouses to provide support during weight loss has had modest success rates.

Jelly Beans Experiment - Redden

Procedure
- Gave 135 people 22 jelly beans each, one at a time.
- As each bean dispensed, information on bean was given.
- One group saw general information, another group saw specific flavour details.

Findings
- Participants got more bored with eating beans if they saw the general information.
- Detailed group enjoyed the experiment.

Lowe et al (2004) 

- Weight losses achieved through WeightWatchers were reasonably maintained over a five-year period and that an average of 71.6% of people maintained a loss of 5% of body weight or more.

Bartlett (2003) 

- Dieting is most successful when goals are realistic and objectively defined.
- Optimal target levels centre around reducing calorific intake by 500-1000 calories per day for a six month period.