Abstract
(1) Background: Adolescence is a critical period when dietary choices are a major concern. It is therefore important to understand the psychological factors that explain these choices. The objective of this study was to assess the predictive role of perceived self-efficacy for healthy eating and weight regulation on healthy and unhealthy eating behavior through the mediation of autonomous motivation, controlled motivation, amotivation, and perceived barriers to daily mechanisms affecting healthy consumption. (2) Methods: A total of 994 adolescents between 15 and 19 years old from Mexico and Spain participated in the study. The Spanish versions of the healthy eating and weight self-efficacy questionnaire, the behavioral regulation in exercise questionnaire, the barriers to healthy eating scale, and the weight-related behaviors scale questionnaire were used to measure the variables of interest. (3) Results: Mediated serial regression analysis showed that barriers to healthy eating (the daily mechanism of food consumption) reduced healthy eating choices. Healthy eating and weight self-efficacy also showed a positive significant relationship with autonomous motivation and a negative relationship with controlled motivation and amotivation. All the types of motivation showed a positive relationship with barriers to healthy eating. (4) Conclusions: The results point out the need to enhance self-efficacy, promote autonomous motivation, and reduce perceived barriers in young people with respect to healthy eating.