Increasing fruit and vegetable consumption using implementation intentions

Developing interventions to increase fruit and vegetable consumption is an important goal for health professionals due to accumulated evidence for their health protective effects. The main aim of this thesis is to test the efficacy of implementation intention-based interventions to increase fruit and vegetable intake in a young adult, student popUlation. The thesis consists of three broad sections: an introductory Chapter; four empirical Chapters, and a general summary and discussion. First, justification for the study of fruit and vegetables for health promotion is provided. This is followed by an introduction to the theoretical background and operation of implementation intentions. A systematic review of previous work applying implementation intentions to fruit and vegetable intake is pre~ented, generating the more specific aims and directions of the thesis. Chapter 2 tests an intervention designed to improve the long-term efficacy of implementation intentions. 'Booster' implementation intentions are found to improve their long-term impact, whilst ruling out the potential for demand characteristics. The third and fourth Chapters investigate whether interventions to increase fruit and vegetables could be improved by separating the two food groups; suggesting that fruit is more amendable to change than vegetable intake and that the behavioural strategies governing their consumption are distinct. Chapter 5 combines 'action' and 'coping' planning with the booster concept of Chapter 1. Preliminary support is generated for the value of the intervention in promoting long-term behaviour change. Finally, Chapter 6 summarises and evaluates the empirical work presented in the thesis, and compares the findings to the systematic review of Chapter 1. Potential ivlimitations are highlighted. Conclusions which can be drawn from these studies and their implications for the existing research literature are discussed.