On 4 December 2013, 'Washoku, traditional dietary cultures of the Japanese, notably for the celebration of New Year' was inscribed on the UNESCO list of Intangible Cultural Heritage. This occurrence inspired extensive efforts on the part of the Japanese government towards Washoku promotion, including symposia, cooking competitions, and even the setting up of a Washoku Day, celebrated for the first time on 24 October 2014. Those activities have transformed a common noun, for decades used to indicate Japanese food or a Japanese-style meal, into a carefully scripted brand name referring specifically to 'traditional Japanese cuisine'. The case of Washoku teaches us a valuable lesson about how a UNESCO designation can be manipulated for the purposes of gastrodiplomacy and national branding, ultimately leading to harmful consequences in terms of preserving historical truth.