This paper focuses on estimates of the Australian population's (including women of child bearing age, the target group for folic acid fortification) intake of folic acid from voluntary and mandatory fortified foods, and not their intake of total dietary folate from all foods consumed. Folic acid as used in this paper refers to added folic acid in the fortified foods reported as consumed by the respondents of the two national food consumption datasets used for the dietary modelling. Folic acid is the chemical form of folate normally used by the food industry as a fortificant.
FSANZ is able to estimate the target population's intake of folic acid because the Australia New Zealand Food Standards Code (the Code) clearly specifies foods that can be fortified under the voluntary and mandatory fortification permissions. Before implementation of the mandatory folic acid fortification standard, specific foods in the Australian market could be fortified under the voluntary folic acid permission outlined in Standard 1.3.2 of the Code. It was therefore possible to identify these foods that individuals reported as consumed and apply a factor accounting for the relevant market share of fortified to unfortified product in the dietary modelling, using data obtained from the food industry for each food category. Where permissions for foods or food groups to be voluntarily fortified with folic acid had not been taken up by industry, these foods or food groups were not included in the model. In addition, because the mandatory folic acid fortification standard relates only to wheat flour for baking bread, it was possible to identify foods consumed that have been fortified with folic acid under the mandatory standard. The estimates did not take into account naturally occurring folates in the foods consumed by the respondents, or folic acid from the use of folic acid supplements or multivitamin supplements containing folic acid.
In developing the folic acid fortification standard, estimates of natural folate and total dietary folate equivalent intakes for the Australian population were previously presented by FSANZ and are not further discussed here [1
]. Although the total folate contents of the bread samples were also determined, they are not presented in this paper but were used to validate our folic acid content results and for updating the national food composition database, which FSANZ maintains [2
Australia implemented mandatory folic acid fortification of wheat flour for making bread in September 2009. The purpose was to reduce the incidence of neural tube defects (NTDs) by increasing the intake of dietary folic acid among women of child-bearing age (16–44 years), the target population.
It had been estimated that between 300 and 350 pregnancies were affected by NTDs each year in Australia [3
] and that the numbers were higher in Indigenous communities [4
]. The total dietary folate intake of the target population had remained well below recommended levels despite the various health programs that had been initiated since 1993 to encourage women of child-bearing age to increase their intake of foods high in natural folates and/or folic acid supplements [5
In Australia, the mandatory folic acid fortification standard applies only to wheat flour for making bread. However, the standard exempts wheat flour for making bread represented as “organic” from the fortification requirement. The exemption allows the organic wheat flour milling industry and bread manufacturers to comply with the fair trading legislation (Australia, Trades Practices Act 1974), which takes precedence over the Code.
Wheat flour for making bread was selected as the food vehicle for fortification because bread is widely consumed by the population, including the target group. In proposing the mandatory folic acid fortification level for wheat flour, FSANZ considered a number of national scenarios, available scientific evidence, and the experiences of other developed countries that had instituted mandatory folic acid fortification of flour. The fortification level was set as a range of 200–300μ
g folic acid per 100
g wheat flour. The Australian level has been set as a range to reduce industry overages, taking into account that a degree of uncertainty exists with regard to the effects of long-term increased folic acid intake by the nontarget population, especially children.
Countries such as the United States of America (USA) and Canada that have mandated folic acid fortification of wheat flour have not prescribed a fortification range. For example, the USA food standard requires each pound of enriched flour (fortified flour) to contain 0.7 milligrams of folic acid [6
]. This translates to approximately 154μ
g folic acid per 100
g of flour. In Canada flour, white flour, enriched flour, or enriched white flour are required to contain 150μ
g folic acid per 100
g of flour [7
In Australia, the mandated level of folic acid in wheat flour for making bread was expected to increase the average intake of folic acid among the target group by 100μ
g/day. This would be above the levels already achieved through use of foods voluntarily fortified with folic acid and use of dietary supplements. It had been estimated that the target population's intake of folic acid from voluntarily fortified foods (including breakfast cereals and yeast-based spreads) was about 108μ
g folic acid per day. The estimated additional 100μ
g folic acid from mandatory fortification of bread was expected to increase total folic acid intake (from voluntary and mandatory fortified foods) and bring about the reduction in number of NTD-affected pregnancies by up to 14%.
FSANZ's role in determining the postfortification levels of folic acid in bread and assessing the population's (including the target group) intake of dietary folic acid is part of the national activities to monitor the mandatory folic acid fortification standard, which includes monitoring of NTD affected pregnancies. The monitoring activities for Australia and New Zealand are described in two recent reports published by the Australian Institute of Health and Welfare (AIHW) [8
], with pre-fortification data for the prevalence of NTDs in Australia also recently published by the AIHW [9