Background: Plant-based diets are becoming more and more widespread among the Spanish population, progressively replacing the Mediterranean dietary pattern. Different studies have shown the motivations for adherence to these diets, and others have highlighted some health advantages and disadvantages. Purpose of the study: Further studies are needed to define the socio-demographic determinants that influence the choice of a plant-based diet and to study the relationship that the choice of dietary pattern has on the health and lifestyle habits of the population. Methods: A descriptive, cross-sectional study was conducted on the Spanish population. The NutSo-HH questionnaire, developed and validated by the research team, was used to gather socio-demographic, nutritional, social, and lifestyle information through non-probabilistic snowball sampling. Results: The questionnaire was completed by 22,181 Spanish citizens, of whom only 19,211 were of interest to the study. The socio-demographic variables gender, age, educational level, income level, and place of residence do not seem to influence the prevalence of a plant-based diet (n = 1638) compared to a Mediterranean diet (n = 17,573). People following a vegetarian or vegan diet have a lower BMI, and they consume less fried food, fast food, and ultra-processed dishes and fewer energy drinks or sugary beverages. They also do more exercise and sleep longer hours, smoke less, and consume alcohol less frequently. However, there seem to be more diagnosed eating disorders among people who follow a plant-based diet than those who follow a Mediterranean diet. Conclusions: People who adopt a plant-based diet tend to exhibit healthier lifestyle patterns and consume fewer foods that are detrimental to their health. However, it is essential for such dietary choices to be supervised by healthcare professionals to mitigate the risk of maladaptive behaviors evolving into eating disorders.

This study used Explainable Artificial Intelligence (XAI) with SHapley Additive exPlanations (SHAP) to examine dietary and lifestyle habits in the Spanish population and identify key diet predictors. A cross-sectional design was used, employing the validated NutSo-HH scale to gather data on nutrition, lifestyle, and socio-demographic factors. The CatBoost method combined with SHAP was applied. The sample included 22,181 Spanish adults: 17,573 followed the Mediterranean diet, 1425 were vegetarians, 365 were vegans, and 1018 practiced intermittent fasting. Fish consumption was the strongest dietary indicator, with vegans abstaining and some vegetarians consuming it occasionally. Age influenced diet: younger individuals preferred vegan/vegetarian diets, while older adults adhered to the Mediterranean diet. Vegans and vegetarians consumed less junk food, and intermittent fasters were more physically active. The model effectively predicts the Mediterranean diet but struggles with others due to sample imbalance, highlighting the need for larger studies on plant-based and intermittent fasting diets.

The aim of this study was to investigate the changes in habits regarding the health and lifestyle of the Spanish population during and after the COVID-19 pandemic. A cross-sectional design was used. Data were collected during the pandemic from 22,181 participants and after the pandemic from 3907 participants using the NutSo-HH Scale, assessing demographic, nutritional, and lifestyle variables. Key findings reveal a slight increase in exercise duration (+6.61%) post-pandemic, along with reductions in fried food (−3.57%), juice (−6.45%), and alcohol consumption (−9.66%). Conversely, there were notable increases in the consumption of ultra-processed foods (+2.16%), soft drinks (+6.47%), and coffee/energy drinks (+38.95%). Sleep quality, body image, and self-perceived health showed minor declines. These findings indicate that despite some positive behavioral changes, there is still a significant dependence on unhealthy dietary choices, negatively impacting both mental and physical health. The results highlight the need for public health strategies which encourage healthier eating, increased physical activity, and better sleep quality to reduce the long-term effects of lifestyle changes brought on by the pandemic. Focused interventions are necessary to curb the rising consumption of ultra-processed foods and sugary beverages while fostering overall well-being. This study underscores the vital role of ongoing surveillance and customized public health initiatives to enhance general health in the post-pandemic era.