3. Results
We screened 557 participants in this randomised controlled trial. A total of 425 individuals were not allocated for randomisation because they did not respond to the invitation by postal mail (The results of the two-way ANOVA analyses showed significant time-by-group interaction effects for the intrinsic motivation to change eating habits and amotivation, with large effect sizes (ηp2 ≥ 0.032; After adjusting the ANOVA results for baseline data, the post hoc tests showed higher intrinsic motivation to change eating habits (mean difference of 0.9, 95% CI [0.1, 1.6]; 