The confinement caused by the COVID-19 pandemic led to changes in people’s lifestyles, which in part provided an opportunity to develop habits at home. The aims were: (1) to verify if the psychological well-being (PWB) of people related to healthy habits, and if physical activity (PA) and diet mediated this relationship; (2) to test if there were differences in this model of relationships between women and men; (3) to analyze if there were differences in healthy habits, PA, diet, and PWB depending on gender; (4) to test if there were differences in healthy habits, PA, diet, and PWB depending on living area; (5) and to assess if there were interaction effects of gender and living area in healthy habits, PA, diet, and PWB. Using a cross-sectional design, we obtained a sample of 1509 participants (18–78 years, 1020 women). Diet and PA fully mediated the relationship between PWB and healthy habits, and women developed more healthy habits than men, whereas men had higher levels of PA and PWB. We also found that people who lived in rural areas during confinement practiced more PA and had lower PWB levels than those who lived in urban areas. These results can help in the planning of strategies to promote healthy habits.
