Determinants of adherence to sustainable healthy diets among Portuguese adults

Abstract

Introduction

Individual food consumption has health implications and direct and indirect environmental impacts. However, knowledge of the determinants of adherence to sustainable healthy diets is still scarce.

Purpose

Analyze the influence of sociodemographic factors (sex, age, marital status, household composition, education, and urbanization degree), body mass index (BMI), physical activity, and diet quality (nutrient adequacy ratio – NAR) on the adherence to the Sustainable HEalthy Diet (SHED) Index and its sub-scores among Portuguese adults.

Materials and methods

Data for this cross-sectional study were obtained from a convenience sample of adults through the completion of a self-reported questionnaire, including sociodemographic information, adherence to the SHED Index, physical activity level (International Physical Activity Questionnaire), and dietary intake (semi-quantitative food frequency questionnaire). Multivariate linear regressions models were used to analyze the associations between factors and the SHED Index and its sub-scores.

Results

A total of 347 participants (64.6 % women) with a median age of 27 years old (P25:20; P75:50) were included. Multivariate regression showed an association of sex (B_male = −4.286,p < 0.001), age (B = 0.263,p < 0.001), urbanization degree (B_rural = 2.465,p = 0.034), and education (B_secondary = 4.244,p = 0.021;B_{college/university} = 5.821,p = 0.001) with SHED Index scores. Furthermore, sex and age were associated with most sub-scores, marital status with Buy Fruits Vegetables and Water sub-scores, physical activity with Water sub-score, and both NAR and education with Healthy Eating sub-score.

Conclusions

Findings suggest that sex, age, urbanization degree, and education level are associated with adherence to a sustainable healthy diet. Physical activity and diet quality were also shown to be associated with the SHED Index sub-scores of Water and Healthy Eating, respectively.