Dietary planning, self-efficacy, and outcome expectancies play a role in an online intervention on fruit and vegetable consumption

OBJECTIVE: An online intervention to improve fruit and vegetable (FV) intake examines the role of planning, outcome expectancies, self-efficacy and gender. Women are not only expected to eat more FV than men, but they are also expected to be more responsive to nutritional advice and benefit more from treatment. METHOD: A two-arm digital intervention with 269 men and 395 women (Mage = 41.2, SDage = 11.45; range: 19-66 years) was conducted in Italy, Spain and Greece, followed up at three and six months, comparing a static with a dynamic, feedback-intensive platform. RESULTS: Linear mixed models yielded an increase in FV consumption in both the dynamic and the static intervention arms. In men, outcome expectancies were positively related to follow-up FV intake. Dietary planning interacted with self-efficacy on behavioural outcomes. CONCLUSION: FV intake increased overall, and being a woman and involvement in planning facilitated behaviour change. Women seemed to be more engaged in the dynamic platform resulting in a higher amount of planning. Initial motivation, as indicated by outcome expectancies, seemed to be beneficial for men. Self-efficacious individuals benefitted from their engagement in planning, but self-efficacy did not compensate for failing to plan.