Comparison of pre-diagnosis dietary intake of women with gestational diabetes mellitus to dietary recommendations

Abstract

The prevalence of Gestational Diabetes Mellitus (GDM) increased from 7% to 13.1% between 2013 and 2017 in NSW, Australia. Limited detail has been reported on dietary patterns prior to GDM diagnosis.

Aim: To evaluate adequacy of micronutrient intakes and contribution of nutrient-dense versus energy-dense, nutrient-poor food groups to total energy.

Method: Dietary intake of women with GDM was assessed over the six months prior to attending the first outpatient nutrition education group using the Australian Eating Survey: food frequency questionnaire with food group serves compared to the Australian Guide to Healthy Eating recommendations. Nutrient intakes compared to Estimated Average Requirements (EARs). Diet quality was evaluated using the Australian Recommended Food Score diet quality index.

Results: Fifty women with a mean age of 30.8±4.6 years completed the Australian Eating Survey. Mean percentage (SD) energy intake derived from nutrient-dense versus energy-dense, nutrient-poor foods was 66.6% (12.4) and 33.4% (12.4); respectively. Median intakes of iron, calcium, fibre, iodine and folate were below EARs. Median (IQR) total Australian Recommended Food Score was 31(15) from a maximum 73 points. Adherence to the Australian Guide to Healthy Eating recommendations was low, with no participants meeting recommendations for serves of bread and cereals, 92% below dairy and dairy alternatives and 82% below vegetable intake recommendations.

Conclusions: Before being diagnosed with GDM, women derive a high percentage of total energy from energy-dense, nutrient-poor foods, have low dietary variety amongst nutrient-dense foods, and sub-optimal intakes of key pregnancy micronutrients. Poor dietary patterns require attention within medical nutrition therapy for GDM in order to optimise nutrition-related health outcomes.

Keywords: Diet; Gestational diabetes mellitus; Medical nutrition therapy; Nutrition.