In 2003 an executive order was issued banning industrially produced trans-fatty acids above a low level in food items in Denmark. To date, only a few other countries have followed Denmark’s example. The way health consequences of trans fats were translated by the different actors enabled the creation of alliances between researchers, politicians, administration and industry. Danish researchers interpreted the research in a way to suit their ‘mental maps’ and to support their initially set goal to reduce industrially produced trans fats. The process displayed a ‘co-production’ where research and policymaking influenced research interpretations.