Updating the University of Otago Food Cost Survey

Abstract

Introduction:Internationally Food Cost Surveys are a method for monitoring the cost of a basic and/or nutritious diet over time. Monitoring the cost of food is important to determine how affordable it is for individuals and families to purchase a basic healthy diet. The New Zealand Food Cost Survey provides an estimate of the cost of a basic, moderate and liberal diet for specific age and gender groups.

The ‘food basket’ is the primary survey tool used in the New Zealand Food Cost Survey. The existing food basket contains 149 foods within 18 food categories. The food basket should comprise foods that represent a typical and nutritious New Zealand diet. However the existing food basket has not been checked against nationally representative food consumption data. Moreover all foods in the existing food basket categories are equally weighted and receive an equal allocation of food category cost. In reality some foods are more commonly consumed than others and therefore should receive a greater allocation of cost. Objectives: This thesis is one of two projects with the aim of updating the existing food basket. The primary objectives of this thesis were to update the food basket based on nationally representative food consumption data as well as calculate percentage weightings to be allocated to foods within each food category. Methods: The 2008/2009 Adult Nutrition Survey (2008/2009 ANS) (n=4721) is a nationally representative survey appropriate for updating the existing food basket. The 2008/2009 ANS 24-hour diet recall food consumption data was used to determine which foods were included or excluded from the existing food basket. Microsoft Excel was the software used to organise and calculate final food consumption frequencies from 2008/2009 ANS data. Results: The updated food basket contains 139 foods within 19 food categories. Many food categories of the existing food basket did not require revision as their contents were already representative of typical New Zealand food consumption. The most revision was required in the meat category, as trends in New Zealand meat consumption have changed considerably over the last three decades. Conclusion: The updated food basket is representative of typical New Zealand food consumption and has weighted percentages calculated for all food categories. With further checks against nutritional guidelines the updated food basket will produce a more accurate cost for a basic, moderate and liberal diet.