Outcomes of folic acid fortification in Australia
Mandatory folic acid fortification in Australia has increased the level of folic acid in the food supply, and thereby increased folic acid intakes and folate status among women of child-bearing age (the target population) (Table 1). The rate of neural tube defects has decreased following mandatory folic acid fortification by 14.4%, in line with predictions. The decrease in neural tube defects has been most substantial for teenagers and Aboriginal and Torres Strait Islander women.
| Key monitoring question and measurement | Pre-mandatory fortification | Post-mandatory fortification | Further details | Outcome |
|---|---|---|---|---|
|
Has the level of folic acid in our food supply increased? |
20–29 µg/100 g |
134–200 µg/100 g |
The predicted post-fortification estimate was 120 µg/100 g in bread. |
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|
Are the food industries adequately complying with the mandatory fortification standards? |
Not applicable |
Mills and baking businesses have systems in place to ensure compliance. |
|
|
|
Have folic acid intakes of women of child-bearing age increased? |
102 µg/day |
247 µg/day (145 µg/day increase; 142%) |
The predicted post-fortification predicted increase was 100 µg/day. |
|
|
Has the folate status of women of child-bearing age improved? |
Serum folate data are available for limited assessment. |
Red blood cell folate |
Mean serum folate levels post‑fortification were higher than at baseline; however, results must be interpreted with caution because different methodologies were used (see Section 2.4). |
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|
Has the incidence of neural tube defects (NTDs) decreased? |
Total study population |
Total study population |
The predicted post-fortification predicted average decrease in NTDs was 14%. |
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Does mandatory folic acid fortification result in adverse health effects for the population? |
Women aged 16–44: 0% |
Women aged 16–44: 0% |
Minimal change in adults exceeding the UL. A higher proportion of children aged 2–16 exceeded the UL but is not considered a health risk. The UL incorporates a fivefold safety margin and is based on an end point for high intakes in older adults. |
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Cancer and all-cause mortality |
|
No increase in cancer or all-cause mortality can be directly associated with increase in folic acid intakes in adults. |
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Desired outcome achieved
Partial achievement
Not applicable: data did not support an overall assessment or a rating was not appropriate.
µg microgram
NTD neural tube defect
UL upper level of intake (for more information, see the Nutrient Reference Values for Australia and New Zealand website)
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Analysis omitting New South Wales from the study population was undertaken as a sensitivity analysis to assess the potential bias of missing data from the state. Inclusion of New South Wales provided a much larger population and improved the study power.