A key step toward developing appropriate evidence-based public health nutrition policies is determining exactly how that evidence should be collected and assessed. Despite this the extent to which different evidence bases influence policy selection is rarely explored. This article presents an epistemological framework which offers a range of considerations affecting this process generally and with particular implications for both micronutrient requirements and the role of behavior in the policy-making process. Qualitative case study data covering 6 European countries/regions (Czech Republic, Italy, the Netherlands, Nordic countries, Poland, and Spain), and three micronutrients (folate, iodine, and vitamin D), have been presented to illustrate the relevance of the Framework.