indicates folic acid intakes for individuals who always avoid the products that contain folic acid; the upper bound indicates folic acid intakes for individuals who always select the products that contain folic acid. The results from the ‘market share’ model are indicated by the black line within the range of estimated folic acid intakes, and are representative of mean population intakes over a period of time. Generally, the results presented in this section refer to the ‘market share’ model results.
The ‘consumer behaviour’ model range of results gives an indication of the uncertainty of the outcome of the current (Baseline) voluntary fortification approach for estimating folic acid intakes compared to the outcome for the Mandatory Fortification scenario. The differences in potential ranges of intakes between Baseline and Mandatory Fortification scenarios indicate that bread and bread products make a significant contribution to total folic acid intakes. By mandating or fixing the level of folic acid in wheat flour for making bread in Australia, the choice for consumers is limited for that one type of food but the certainty of outcome of fortification increases considerably. The estimated mean dietary folic acid intakes for New Zealand did not show as large a range as for Australia. This could be due to differences in the uptake of voluntary folic acid fortification between the two countries, being lower in New Zealand.
The ‘consumer behaviour’ model results indicate that, for an individual who eats large amounts of the fortified foods and goes out of their way to select the fortified version wherever there is a choice, then higher folic acid intakes can be achieved. However, it is considered that the number of consumers who would actually behave in this way on a regular basis is likely to be small.
Figure 5: Comparison between estimated mean dietary folic acid intakes at Baseline and Mandatory Fortification for Australian and New Zealand population groups.
4.1 Estimated dietary folic acid intakes for women of child-bearing age
The estimated mean dietary folic acid intakes for Australian and New Zealand women of child-bearing age are shown in Table 1 and Figure 6 for Baseline and Mandatory
Fortification scenarios. There was an incremental increase in folic acid intakes for women of child-bearing age from Baseline to Mandatory Fortification: +100 μg/day for Australia and +140 μg/day for New Zealand. While the estimated mean dietary folic acid intakes showed a higher increase from Baseline to Mandatory Fortification for New Zealand than Australia, New Zealand women aged 16-44 years had a lower Baseline estimated mean folic acid intakes (62 àg/day) in comparison to Australian women (108 àg/day). The introduction of mandatory folic acid fortification of ‘wheat flour for making bread’ for Australia and ‘all breads’ for New Zealand would result in women aged 16-44 years in both Australia and New Zealand having similar estimated mean dietary folic acid intakes – 208 àg/day for Australia and 202 àg/day for New Zealand. Full results can be found in Appendix 3, Tables A3.1.a and b for Australia and New Zealand, respectively.
Estimated mean dietary folic acid intakes from food alone for women of child bearing age did not achieve the desired folic acid intake of 400 àg/day for any of the scenarios examined (i.e.
Baseline voluntary fortification v/s Mandatory Fortification). Further details on the
proportion of the target group whose estimated dietary folic acid intakes met the 400 μg/day folic acid target can be found in Table 5.
These results also indicate that New Zealand women of child-bearing age have lower
Baseline folic acid intakes than Australian women. This is because there appears to be lesser uptake of voluntarily folic acid permissions in New Zealand. One of the major areas of difference is that Bakers Delight bread, which represents approximately 15% of the bread market in Australia (Bakers Delight 2006), is not fortified with folic acid in New Zealand, but is fortified in Australia.
Table 1: Estimated mean folic acid intakes from food and increase in folic acid intake from Baseline for women of child-bearing age (16-44 years) #
a. Australia
Scenario Mean dietary folic acid intake
(Increase in folic acid intake from Baseline) μg/day
Market weighted Consumer behaviour
Baseline 108 83 – 243
Mandatory Fortification♦ 208
(+100)
204 – 231
# Number of respondents aged 16-44 years: Australia = 3,178
♦ Mandatory folic acid fortification of ‘wheat flour for making bread’ for Australia
b. New Zealand
Scenario Mean dietary folic acid intake
(Increase in folic acid intake from Baseline) μg/day
Market weighted Consumer behaviour
Baseline 62 60 – 69
Mandatory Fortification♦ 202
(+140) 200 – 209
# Number of respondents aged 16-44 years: New Zealand = 1,509
♦ Mandatory folic acid fortification of ‘all bread’ for New Zealand
Figure 6: Estimated mean dietary folic acid intakes for Baseline and Mandatory
Fortification scenarios for Australian and New Zealand women of child-bearing age (16-44 years)
4.2 Estimated dietary folic acid intakes for the non-target groups
Dietary folic acid intakes were estimated for the non-target groups to assess the impact that Mandatory Fortification would have on public health and safety. Figure 5 shows the
estimated mean dietary folic acid intakes for the target group (women aged 16-44 years) and various other non-target groups. The results show an increase in estimated mean dietary folic acid intakes from Baseline to the Mandatory Fortification scenario for all non-target groups.
As for women of child-bearing age, non-target groups in New Zealand also have lower Baseline folic acid intakes compared to Australia, with similar estimated mean dietary folic acid intakes for New Zealanders aged 15 years and above (236 àg/day) and Australians aged 2 years and above (244 àg/day) under Mandatory Fortification. Full results for the estimated dietary folic acid intakes for the non-target groups are in Appendix 3: Table A3.2 for Australia and Table A3.3 for New Zealand.
4.3 Major contributors to estimated folic acid intakes
The major food contributors for both Australia and New Zealand to total folic acid intake (≥5%) were calculated for women of child bearing age and the general population for both Baseline and Mandatory Fortification scenarios. The major contributing foods to folic acid intakes for Australian children aged 2-3 years and 4-8 years were also analysed. The results are shown in Table 2.
At Baseline, breakfast cereals were the major contributors to folic acid intakes for both the Australian and New Zealand populations. Yeast extracts and breads were also major contributors to the Australian population’s intakes of folic acid. For New Zealand, yeast extracts were a major contributor at Baseline but breads were not.
For the Mandatory Fortification scenarios, bread was the major contributor to folic acid intakes for both Australia and New Zealand. Breakfast cereals and yeast extracts were the other major contributors to folic acid intakes for Australia and New Zealand for the
Mandatory Fortification scenarios. While breakfast cereals were a major contributor to the folic acid intakes of the target group under current voluntary fortification levels (Baseline), they were not consumed by as large a proportion of the target group as breads.
Table 23: Major contributors (>5%) to folic acid intakes at Baseline and Mandatory Fortification scenarios for Australia and New Zealand
Country Population
group Scenario Major contributors (%)
Breads Breakfast cereals Yeast extracts Australia 2 years and
above
Baseline 19 51 24
Mandatory Fortification♦
55 27 13
2-3 years Baseline 15 45 28
Mandatory Fortification♦
46 28 17
4-8 years Baseline 16 48 31
Mandatory Fortification♦
49 28 18
Females 16-
44 years Baseline 20 47 28
Mandatory
Fortification♦ 56 24 14
New
Zealand 15 years and
above Baseline <1 61 35
Mandatory
Fortification♦ 69 19 11
Females 16- 44 years
Baseline 1 58 37
Mandatory
Fortification♦ 70 18 11
♦ Mandatory folic acid fortification of ‘wheat flour for making bread’ for Australia and mandatory folic acid fortification of ‘all bread’ for New Zealand
Note: the shaded cells indicate that the food is not a major contributor to folic acid intakes
4.4 Risk characterisation
The estimated folic acid dietary intakes were compared with the Nutrient Reference Value (NRV) called an Upper Level (UL) to determine if the proposed level of addition of folic acid to ‘wheat flour for making bread’ (Australia only) or bread (New Zealand only) might be a concern to public health and safety. The UL is ‘the highest average daily nutrient intake level likely to pose adverse health effects to almost all individuals in the general population’
(National Health and Medical Research Council, 2006). The ULs for folic acid for pregnant and lactating women are 800 àg/day for 16-18 year old women and 1,000 àg/day for 19-44 year old women. The ULs for other population groups are given in Table 4.
The estimated dietary intakes for folic acid were determined for each individual and were compared to the relevant UL for the individual’s age group and gender. The proportion of the target group exceeding the UL is shown in Tables 3a and b for Australia and New Zealand, respectively. The tables illustrate that less than 1% of women aged 16-44 years exceed the UL at Baseline and Mandatory Fortification.
Table 3: Proportion of respondents with folic acid intakes above the Upper Level for women of child-bearing age (16-44 years)#
a. Australia
Scenario % of respondents with folic acid intakes >UL
Baseline <1
Mandatory Fortification♦ <1
# Number of respondents aged 16-44 years: Australia = 3,178
♦ Mandatory folic acid fortification of ‘wheat flour for making bread’ for Australia
b. New Zealand
Scenario % of respondents with folic acid intakes >UL
Baseline <1
Mandatory Fortification♦ <1
# Number of respondents aged 16-44 years: New Zealand = 1,509
♦ Mandatory folic acid fortification of ‘all bread’ for New Zealand
The proportion of each non-target population group exceeding the UL is shown in Table for Baseline and Mandatory Fortification scenarios for the Australian and New Zealand
populations.
For Australia, the results indicate that children aged 2-3 years and 4-8 years are the most likely of the non-target groups to have intakes exceeding the UL if mandatory folic acid fortification of ‘wheat flour for making bread’ were to be introduced (refer to Table 4 for details). In order for the risk to Australian children aged 2-3 years and 4-8 years to be characterised further, high consumer (95th percentile) intakes of folic acid were investigated and compared to the UL.
Additionally, the maximum estimated dietary folic acid intakes for the ‘consumer behaviour’
model were investigated – i.e. for individual consumer behaviour. The results indicated that the estimated dietary folic acid intakes for Australian children aged 2-3 years and 4-8 years were acceptable.
Full results can be found in Appendix 4, Table A4.1 for Australia and Table A4.2 for New Zealand).
Table 4: Proportion of non-target group respondents with folic acid intakes above the Upper Level
a. Australia
Population
Group Upper
Level (àg/day
)
No. of
respondents % respondents with dietary folic
acid intakes >UL 95th percentile dietary folic acid intakes
àg/day (%UL) Baselin
e Mandatory Fortification♦ Baseline
Mandatory Fortification♦ 2-3 years
300 383 2 9
232 (75%)
338 (110%) 4-8 years
400 977 1 4 282
(70%) 388
(95%)
9-13 years 600 913 1 2
14-18
years 800 734 <1 2
19-29
years 1,000 2,203 <1
<1 30-49
years 1,000 4,397 <1
<1 50-69
years 1,000 3,019 <1 <1
70 years &
above 1,000 1,232 0 0
♦ Mandatory folic acid fortification of all bread making flour for Australia
b. New Zealand Population
Group
Upper Level
(àg/day) No. of respondents
% respondents
with dietary folic acid intakes >UL Baseline
Mandatory Fortification♦
15-18 years 800 246 0 <1
19-29 years 1,000 804 0 <1
30-49 years 1,000 1,883 <1 <1
50-69 years 1,000 1,147 0 <1
70 years &
above 1,000 556 0 0
♦ Mandatory folic acid fortification of all bread for New Zealand