Folate fortification: potential impact on folate intake in an older population

To examine the potential impact of different models of folate fortification of Australian foods on the folate intakes of older Australians.

Dietary data were collected using a food frequency questionnaire from people attending a population-based health study.

Two postcode areas west of Sydney, Australia.

A total of 2895 people aged over 49 y, obtained from a door knock census (79% of 3654 subjects examined).

The folate intake in this population was estimated using four different models: (1) pre-fortification folate values; (2) current voluntary folate fortification in Australia; (3) universal fortification of all foods permitted to add folate, at 25% recommended dietary intake (RDI) per reference serve; and (4) universal fortification of all foods permitted to add folate, at 50% RDI per reference serve. The increased bioavailability of synthetic folic acid (SFA) was included in the analysis.

At current voluntary folate fortification, approximately 65% of this population consume 320 microg dietary folate equivalents (DFE) or more per day from diet and supplements, and 0.4% (n=10) consume greater than the recommended upper safety level of 1000 microg from SFA. More than 95% of this older population would be expected to consume more than 320 microg DFE from diet and supplements with universal fortification at 50% of the RDI, and 0.5% (n=14) may consume greater than 1000 microg/day of SFA.

There is unlikely to be a large increase in the proportion of older persons who are likely to consume more than the upper safety level of intake with universal folate fortification. As most of those who currently or are predicted to consume over 1000 microg SFA take supplements containing folic acid, it is highly recommended that vitamin B12 be included in any vitamin supplements containing folate.

This study was supported by the Australian National Health and Medical Research Council (NHMRC).