The overall health impact of bread fortified with folic acid in the Netherlands has been simulated. The case study showed how the risk–benefit approach may assist a policy maker in decisions on food fortification programs. It illustrates general problems regarding the data demands, the assumptions and uncertainties. A simple sensitivity analysis showed which assumptions were most crucial. Modest fortification (140 μg/100 g bread) seems reasonable to improve public health but the results hinge on the assumptions one makes for the association between colorectal cancer and high folate intake. A precautious policymaker may very well decide against folic acid fortification. The often debated increase in masked vitamin B12-deficiency appears negligible compared to the health gain resulting from prevented neural tube defects.