Adhering to a Mediterranean diet in a Mediterranean country: an excess cost for families?

Adherence to the Mediterranean diet (MD) has been decreasing in southern Europe, which could be linked to several cultural or educational factors. Our aim is to evaluate the extent to which economic aspects may also play a role, exploring the relationship between food prices in Portugal and adherence to the MD. We evaluated data from the Portuguese National Food, Nutrition, and Physical Activity Survey (IAN-AF 2015-2016) (n 3591). Diet expenditures were estimated by attributing a retail price to each food group, and the diet was transposed into the Mediterranean Diet Score used in the literature. Prices were gathered from five supermarket chains (65 % of the Portuguese market share). Linear regression models were used to assess the association between different adherence levels to the MD levels and dietary costs. Greater adherence to the MD was associated with a 21·2 % (P < 0·05) rise in total dietary cost, which accounts for more 0·59€ in mean daily costs when compared with low adherence. High adherence individuals (v. low adherence) had higher absolute mean daily costs with fish (0·62€/+285·8 %; P < 0·05), fruits (0·26€/+115·8 %; P < 0·05) and vegetables (0·10€/+100·9 %; P < 0·05). The analysis stratified by education and income level showed significantly higher mean daily diet cost only amongst higher income groups. Our findings suggest that greater adherence to the MD was positively and significantly associated with higher total dietary cost. Policies to improve population's diet should take into consideration the cost of healthy foods, especially for large low- and middle-income families.

Interaction effects of socio-economic position in the association between eating location and diet quality in Portuguese children and adolescents: results from the National Food, Nutrition and Physical Activity Survey 2015-2016.

This study aims to evaluate the interaction effect of socio-economic environment (SEE) in the relationship between the eating location (EL) and diet quality, in children and adolescents. Data included Portuguese children and adolescents (3-17 years) from a National Dietary Survey Sample (IAN-AF 2015/2016, n 987). Dietary intake was obtained by 2-d food diaries (children) or 2-24-h-recall (adolescents). Participants were classified into four groups of EL: 'Home', 'Other homes', 'School' and 'Restaurants'. Diet quality was measured as a higher adherence to a healthy eating pattern. A previous developed socio-economic classification was used, and participants were grouped as belonging to a low socio-economic environment (LSE) or middle-high socio-economic environment (MHSE). Linear regression models were used to evaluate the association between EL and diet quality, stratified by the SEE. A statistically significant interaction effect was found (P < 0·01) for the SEE in the association between EL and diet quality. After adjustment for potential confounders, in LSE, participants belonging to 'Other homes' (ß = -2·07; 95 % CI:-3·70, -0·44) and 'Restaurants' (ß = -3·31; 95 % CI: -5·08, -1·54) had lower scores in the diet quality score, comparing to 'Home'. In MHSE, comparing with 'Home', 'Restaurants' showed lower diet quality (ß = -1·56; 95 % CI:-2·65, -0·48), while the 'School' had better diet quality (ß = 0·90; 95 % CI: 0·16, 1·64). The SEE influences the association between EL and diet quality and, belonging to more disadvantaged SEE, might represent a higher risk of unhealthy eating habits when eating out-of-home.