Relationships among mediterranean diet adherence, sustainable food literacy, and depression in healthcare professionals | BMC Health Services Research

Comparisons of participants’ Mediterranean Diet Adherence Screener (MEDAS) scores, sustainable food literacy subdimensions (knowledge I and II, food and culinary skills, attitudes, action strategies, and total score), and total BECK scores were conducted according to gender, marital status, education level, smoking status, alcohol use, and the presence of chronic disease (Table 1).

A total of 251 healthcare professionals participated in the study, of whom 60.2% (n = 151) were female. The mean age was 33.01 ± 6.82 years (range: 20–61). With respect to marital status, 61% were married, and 39% were single. In terms of education, 68.9% held a bachelor’s degree, 16.3% held an associate’s degree, and 14.7% held a postgraduate degree. Among the participants, 31.9% were smokers, and 12% reported alcohol use. The prevalence of chronic disease was 17.1%. The most common conditions were asthma (n = 7) and hypertension (n = 5), followed by Hashimoto’s thyroiditis (n = 3), hypothyroidism (n = 2), and single cases of other chronic diseases (anxiety disorder, fibromyalgia, celiac disease, rheumatoid arthritis, type 2 diabetes mellitus, and other chronic illnesses). With respect to dietary habits, 58.6% reported not skipping main meals, and only 24.7% engaged in regular physical activity.

Gender-based analysis revealed that women scored significantly higher than men did on Knowledge II (p < 0.001), food and culinary skills (p = 0.025), attitudes (p = 0.029), action strategies (p = 0.023), and total sustainable food literacy scores (p = 0.011), whereas no significant difference was found in BDI scores (p > 0.05). Nonsmokers had significantly higher MEDAS scores than smokers did (p = 0.037). Compared with those without chronic disease, participants with chronic disease had significantly higher BECK scores (p = 0.034). No significant differences were observed in scale subdimensions and total BECK scores according to marital status, education level, or alcohol use (p > 0.05). Among the 14 items of the MEDAS, the lowest adherence rates were found for wine (mean = 0.004), fish and seafood (mean = 0.012), and fruit consumption (mean = 0.06). In contrast, the highest adherence was noted for using tomato, garlic, onion, or leek sauces in vegetable dishes (mean = 0.71) and for preferring white meat instead of red or processed meat (mean = 0.79).

Table 1 Comparison of the MEDAS score, sustainable food literacy subdimensions and Total BECK scores according to demographic variables

Anthropometric measurements, including weight, height, body mass index (BMI), fat percentage, muscle mass, water ratio, and bone mass, were compared according to gender, marital status, education level, smoking and alcohol use, presence of chronic disease, main meal-skipping behavior, and regular physical activity (Supplementary Table 1).

Supplementary Table 1. Comparison of anthropometric measurements of participants according to demographic variables.

Compared with females, male participants had significantly greater weight, height, BMI, muscle mass, water ratio, and bone mass values (all p < 0.001), whereas females had a significantly greater fat percentage (p < 0.001). With respect to marital status, married individuals had greater mean height (p = 0.001), BMI (p = 0.001), muscle mass (p = 0.007), water content (p = 0.014), and bone mass (p = 0.024) than single individuals did.

In terms of education level, participants with postgraduate degrees had a significantly lower fat percentage than did the other groups did (p = 0.021), although no significant differences were observed for the other measurements (p > 0.05). The mean BMI of smokers was significantly lower than that of nonsmokers (p = 0.036), with no further differences in other anthropometric parameters.

Alcohol consumers presented a significantly lower fat percentage (p = 0.001) but greater muscle mass (p = 0.019) and water ratio (p = 0.010). Participants with chronic diseases had significantly greater BMI values than did those without chronic diseases (p = 0.034). Individuals who skipped main meals had significantly lower body weights than those who did not (p < 0.001).

Finally, participants engaging in regular physical activity presented significantly lower weights (p = 0.005), BMIs (p = 0.024), and fat percentages (p = 0.049), whereas their total body water were significantly greater (p = 0.054).

The participants were classified into minimal, mild, moderate, and severe depression groups according to their Beck Depression Inventory (BDI) scores. The Mediterranean Diet Adherence Screener (MEDAS) and sustainable food literacy subdimension scores across these groups are presented in Table 2.

Significant differences were observed in MEDAS scores (p = 0.047) and scores on the Knowledge I subscale (p = 0.014). Post hoc analyses revealed that participants with minimal depression had significantly higher MEDAS and knowledge I scores than did those with severe depression.

No significant differences were found among the groups in terms of knowledge II, food and culinary skills, attitudes, action strategies, or total sustainable food literacy scores (p > 0.05). Similarly, the anthropometric variables did not differ significantly according to depression level (p > 0.05).

Table 2 Evaluation of sustainable food literacy and MEDAS scale scores according to the BECK depression level

Table 3 summarises the correlations between the MEDAS score and its components with BMI, depressive symptoms (BECK), and Sustainable Food Literacy (SFL) total scores. A significant negative correlation was found between the overall MEDAS score and both BMI (r = − 0.150, p = 0.017) and BECK Total (r = − 0.174, p = 0.006), while a positive association was observed with SFL (r = 0.154, p = 0.015).

Among the MEDAS components, daily use of olive oil (r = − 0.127, p = 0.044) was negatively correlated with depressive symptoms. Red meat consumption showed a positive correlation with BECK scores (r = 0.201, p = 0.001), indicating that higher red meat intake was related to more depressive symptoms. Conversely, weekly nut consumption was negatively correlated with BECK scores (r = − 0.184, p = 0.003) and positively correlated with SFL scores (r = 0.192, p = 0.002). A significant negative correlation was also found between BMI and the use of olive oil–tomato–garlic–based sauces (r = − 0.158, p = 0.012).

Overall, these results suggest that greater adherence to the Mediterranean dietary pattern—particularly lower intake of red meat and sugary drinks and higher intake of olive oil and nuts—is associated with lower BMI and fewer depressive symptoms, alongside improved sustainable food literacy levels.

Table 3 Correlation between MEDAS Score, BMI, BECK total, and sustainable food literacy (SFL) total scores

The relationships between participants’ sustainable nutritional knowledge, attitudes, behaviors, Mediterranean diet adherence (MEDAS), and body composition parameters were examined via Pearson correlation analysis (Supplementary Table 2).

Supplementary Table 2. Associations between sustainable nutritional knowledge, attitudes, behaviors, adherence to the Mediterranean diet (MEDAS) and body components.

The MEDAS score showed weak positive correlations with knowledge II (r = 0.121, p = 0.066), food and culinary skills (r = 0.066, p = 0.401), attitudes (r = 0.011, p = 0.721), and action strategies (r = 0.225, p < 0.001). Among these, the strongest associations were observed with action strategies (r = 0.225, p < 0.001) and the total sustainable food literacy score (r = 0.154, p < 0.001).

Strong and statistically significant positive correlations were identified among the sustainable food literacy subdimensions (all r > 0.6, p < 0.001). The highest correlations were between attitudes and Knowledge II (r = 0.665, p < 0.001) and between action strategies and Knowledge II (r = 0.661, p < 0.001).

BMI demonstrated significant negative correlations with all sustainability subscales (e.g., Knowledge I: r=-0.509, p < 0.001; total score: r=-0.431, p < 0.001). The fat percentage was negatively associated with the total sustainability score (r=-0.437, p < 0.001). MEDAS scores were also negatively correlated with BMI (r=-0.150, p < 0.017).

With respect to other anthropometric measures, muscle mass showed low but significant positive correlations with Knowledge II (r = 0.171, p = 0.005) and the total sustainability score (r = 0.349, p < 0.001). The water content was positively correlated with the total score (r = 0.174, p = 0.004). Bone mass was weakly but significantly correlated with only the Knowledge II subscale (r = 0.180, p = 0.004).

Multiple linear regression analysis was conducted to identify the predictors of Mediterranean Diet Adherence Screener (MEDAS) scores (Table 4). The independent variables included in the model were the Intention and Strategies to Act total score, BECK total score, and body weight (kg). The model explained approximately 5.7% of the variance in MEDAS scores (R² = 0.057).

The analysis revealed that the Intention and Strategies to Act score was a positive and significant predictor of MEDAS scores (B = 0.023, β = 0.145, p = 0.021). In contrast, the BECK total score had a negative and significant effect (B=-0.026, β=-0.141, p = 0.025), and body weight was also identified as a significant negative predictor (B=-0.017, β=-0.127, p = 0.041).

Table 4 Regression analysis for MEDAS (R2: 0.057)

In the second regression model, the total sustainable food literacy score was considered the dependent variable, whereas the BECK total score and muscle mass (kg) were entered as independent variables (Table 5). The model explained 3.9% of the variance in sustainable food literacy (R² = 0.039).

The results indicated that the BECK total score was a significant negative predictor of sustainable food literacy (B=-0.648, β=-0.168, p = 0.007). Similarly, muscle mass also had a significant negative effect on sustainable food literacy (B=-0.471, β=-0.132, p = 0.034).

Table 5 Regression analysis for sustainable food literacy (R2: 0.039)