Association Between Energy Density and Diet Cost in Children

Porto Biomed J. Jul-Aug 2016;1(3):106-111. doi: 10.1016/j.pbj.2016.08.005. Epub 2016 Sep 14.


Highlights: The average of the energy-adjusted diet cost in 6-12 years-old children was 2.17€/1000Kcal (SD + 0.49).Energy-density diets (EDs - Kcal/g) were calculated by three distinct methods: (1) with food and all beverages (ED1), (2) with food and caloric beverages (ED2), and (3) only with food (ED3).The distributions of the three EDs were statistically different, being higher the ED3 - calculated excluding all beverages (1.15Kcal (SD + 0.28) vs. ED2: 1.10Kcal/g; SD + 0.24 vs. ED1: 0.99Kcal/g; SD + 0.22).Lower energy-density diets (EDs) were associated with higher diet cost in a sample of school children from a Mediterranean country, regardless the differences between the EDs calculated by three distinct methods.

Background: Lower energy density diets tend to cost more, but data using different ways to calculate the dietary energy density, is scarce.

Objectives: To estimate the dietary energy density, and to assess how it is associated with the diet cost in children.

Methods: Data were obtained from a community-based survey from public elementary schools in Portugal. Dietary intake of 464 children (6-12 years) was assessed by a 24 h recall in 2007/2008. Dietary energy density (kcal/g) was calculated as following: (1) with food and all beverages (ED1), (2) with food and caloric beverages (ED2), and (3) only with food (ED3). Energy-adjusted diet cost (€/1000 kcal) was calculated based on the collection of food prices from a national leader supermarket. Anthropometric measures were taken and socio-demographic data were obtained from parents. Logistic regression was used to estimate the association between diet cost and energy density.

Results: For boys, the energy-adjusted diet cost of the highest third of energy density was lower, between 81% in the ED3 (p for trend <0.001) and 87% in the ED1 (p for trend <0.001), compared to the lowest third. Girls showed similar, but weaker associations.

Conclusions: Higher dietary energy density was associated with lower dietary cost among children.

Keywords: Dietary energy density and children; Energy-adjusted diet cost.