The role of socio-economic status and energy-density in Australian women of child-bearing age.

Abstract

An optimal diet is imperative in preparing women for pregnancy and this may be influenced by socio-economic status (SES). This research aims to investigate the role of SES on the dietary energy density (ED) in Australian women of preconception age. A secondary analysis of the Australian National Nutrition and Physical Activity Survey 2011-12 for females aged 18-39years (n=1617) was conducted. Dietary intake was assessed by 24-hr recalls and dietary ED by dietary energy per weight (kJ.g-1 ). ED was further categorised as ED of foods and beverages separately. SES was assessed by three variables: Socio-Economic Indexes for Areas (SEIFA), developed by the Australian Bureau of Statistics; income decile; and level of education. Linear mixed model regressions were used to identify associations between ED and SES. The median ED for food, beverages and combined food and beverages was 9.38kJ g-1 , 1.02 kJ g-1 and 7.11kJ g-1 , respectively. No significant variation was explained by SES variables when analysing combined ED in the adjusted model or ED from foods. Income decile reduced ED of beverages, although with little effect (coefficient: -0.04, P=0.002). Significant confounders included inactivity, which increased ED in both combined ED and ED foods (coefficient: 0.51, P=0.001 and coefficient: 0.78, P<0.001). SES explained little variation in dietary ED in women of childbearing age. A large proportion of women had high energy-dense diets regardless of their SES. These findings suggest that a large proportion of women, who may become pregnant, have diets that exceed the international recommendations for dietary energy density.