Mediation of psychosocial determinants in the relation between socio-economic status and adolescents' diet quality.

PURPOSE: To examine the underlying reasons for the positive relation between socio-economic status (SES) and the diet quality of adolescents. METHODS: In 2081 adolescents (12.5-17.5 years) of the European HELENA study, a continuous variable on diet quality via 2-day 24-h recalls was available. SES was reflected by parental education, parental occupation and family affluence. Mediation by several psychosocial determinants was tested: self-efficacy, availability at school and home, social support, barriers, benefits, awareness and some self-reported influencers (parents, school, taste, health, friends, food readily available, easy preparation, hunger, price and habits). Multiple mediation analyses were adjusted for age, sex and country. RESULTS: The availability of soft drinks and fruit at home, social support, parental influence, barriers, price influence, taste influence, health influence and food being readily available were significant mediators. The multiple mediation indirect effect accounted for 23-64% of the total effect. Both occupation and education and both maternal and paternal factors could be explained by the mediation. The unavailability of soft drinks was the strongest mediator (17-44% of the total effect). CONCLUSION: Up to 64% of the positive relation between SES and the diet quality in adolescence could be explained by several healthy eating determinants. Focusing on these factors in low-SES populations can minimize social inequalities in diet and health by improving the diet of these specific adolescents.

Associations between a Mediterranean diet pattern and inflammatory biomarkers in European adolescents.

AIM: To test whether the Mediterranean diet score and each food-subgroup is associated with inflammatory biomarkers in European adolescents. METHODS: In 464 adolescents (13-17 years) of the European HELENA study, data were available on body composition, inflammation markers, and food intake determined by two computerized 24-h recalls. The Mediterranean diet score and its food-subgroups (Vegetables, Fruits and Nuts, Pulses, Cereal and Roots, Monounsaturated/Saturated fat ratio, Dairy, Fish, Meat and Alcohol) were evaluated. A set of inflammation-related biomarkers was measured: IL-1, IL-2, IL-4, IL-5, IL-6, IL-10, TGFß-1, TNF-α, sVCAM-1, sICAM1, sE-selectin, white blood cells, lymphocytes, CD3, CRP, GGT, ALT, and homocysteine. Multivariate and multiple linear regression analyses were adjusted for age, sex, country, socioeconomic status, paternal and maternal education, adiposity, and smoking habits. RESULTS: The Mediterranean diet score was positively associated with CRP, and negatively with sVCAM-1. The subgroups showed the following positive/negative associations: Vegetables with IL-10(+), CRP(+), CD3(+), ALT(+), lymphocytes(+), sE-selectin(-); Fruits and Nuts with IL-4(-), TNF-alpha; Pulses with IL-5(+), IL-6(+), IL-2(-); Cereals and Roots with IL-6(-), IL-10(-); Monounsaturated/Saturated-fat ratio with IL-6(+), TGFß-1(+), sVCAM-1(+boys, -girls), homocysteine(-); Dairy with IL-1(+), IL-5(+), IL-6(+), IL-10(+), TGFß-1(+), homocysteine(-); Fish with homocysteine(-); Meat with IL-2(+), IL-10(+); Alcohol with CRP(+), lymphocytes(-). Sex differences were found. CONCLUSION: Some specific food-inflammation associations were found, suggesting that diet is to a certain extent already related to inflammation in adolescents and can be used in disease prevention. Also some counterintuitive results were found, which might be due to grouping very different foods into a single group, besides considering that the human body may respond differently depending on the interaction between diet, lifestyle, genetics, biochemical individuality, age and sex.