Intake of free sugars and micronutrient dilution in Australian adults

The negative health effect of excessive intake of free sugars has been gaining increasing public awareness.

This secondary analysis aimed to evaluate the impact of free-sugar intake on micronutrient dilution, and estimate a threshold level of free-sugar intake at which a decrease in micronutrient intake becomes evident, based on data from the Australian Health Survey 2011-2012.

Dietary data from adult respondents (weighted n = 6150) who had completed two 24-h recalls were analyzed. A published 10-step methodology was adopted and used to estimate the free-sugar intake of the respondents. Six modified cut-offs for percentage of energy of free sugars (%EFS) were created based on recommendations from the WHO and the Institute of Medicine to examine the association between %EFS on micronutrient intakes. Estimated marginal means and SEs were calculated using ANCOVA. Logistic regression was used to calculate the ORs of not meeting the nutrient reference values for Australia and New Zealand for each micronutrient with an increase in free-sugar intake. Analyses were adjusted for age, sex, socioeconomic status, country of birth, whether dieting, smoking status, and remoteness of living area.

Peak intake for most micronutrients was observed at %EFS between 5% and <15%. A significant reduction in most micronutrient intakes was observed at >25%EFS. At <5%EFS, some micronutrient intakes were reduced. Only small variations in micronutrient consumptions were observed when %EFS was between 5% and 25%. Core food intake decreased and discretionary food increased with an increase in free-sugar intake.

A high free-sugar intake, particularly >25%EFS, was found to have a significant diluting effect on most nutrients. However, a free-sugar intake <5%EFS may increase the risk of undesirably low micronutrient consumption related to inadequate total energy intake. This secondary analysis was registered at anzctr.org.au as ACTRN12617000917336.