Crossing two types of implementation intentions with a protection motivation intervention for the reduction of saturated fat intake: a randomized trial.

Implementation intentions, namely specific plans regarding when, where and how an individual will act, increase the likelihood of action. There is evidence that implementation intentions should be particularly efficacious when combined with motivational interventions. However, this is yet to be tested in relation to the reduction of unhealthy behaviour. Thus the aim of this study was to examine the efficacy of combined motivation and implementation intention interventions for the reduction of saturated fat intake. It also tested a new form of implementation intention (reasoning implementation intentions). Participants from the UK (n = 210) were randomized to condition and asked either to form standard implementation intentions, reasoning implementation intentions, or received no implementation intention manipulation; and were exposed to protection motivation-based information, or not. Results showed that standard and reasoning implementation intentions were successful in reducing the proportion of food energy derived from saturated fat but the effects of the standard implementation intention were dependent on whether participants read the motivational message or not.