Evaluation of the Dutch general exemption level for voluntary fortification with folic acid

Introduction: Fortification with folic acid was prohibited in the Netherlands. Since 2007, a general exemption is given to fortify with folic acid up until a maximum level of 100 μg/100 kcal. This maximum level was based on a calculation model and data of adults only. The model requires parameters on intake (diet, supplements, energy) and on the proportion of energy that may be fortified. This study aimed to evaluate the model parameters considering the changing fortification market. In addition, the risk of young children exceeding the UL for folic acid was studied. Methods: Folic acid fortified foods present on the Dutch market were identified in product databases and by a supermarket inventory. Together with data of the Dutch National Consumption Survey-Young Children (2005/2006) these inventory results were used to re-estimate the model parameters. Habitual folic acid intake of young children was estimated and compared to the UL for several realistic fortification scenarios. Results: Folic acid fortified foods were identified in seven different food groups. In up to 10% of the population, the proportion of energy intake of folic acid fortified foods exceeded 10% – the original model parameter. The folic acid intake from food supplements was about 100 μg/day, which is lower than the intake assumed as the original model parameter (300 μg). In the scenarios representing the current market situation, a small proportion (<5%) of the children exceeded the UL. Conclusion: The maximum fortification level of 100 μg/100 kcal is sufficiently protective for children in the current market situation. In the precautionary model to estimate the maximum fortification levels, subjects with high intakes of folic acid from food and supplements, and high energy intakes are protected from too high folic acid intakes. Combinations of high intakes are low in this population. The maximum levels should be monitored and revised with increasing fortification and supplementation practices.