The nailed heads ritual did not correspond to the same symbolic expression among the Iberian communities of the northeast of the Iberian Peninsula, but rather a practice that differed in each settlement. In some, external individuals were used as symbols of power and intimidation, while other settlements could have given priority to the veneration of members of the local community. This is the conclusion reached by a study led by the Universitat Autònoma de Barcelona (UAB) which analyses the mobility patterns of these human communities existing in the Iron Age of the last millenium BCE. Researchers studied seven nailed skulls of men found in two sites dating back to this period: the city of Ullastret (found in the same town of the province of Girona) and the settlement of Puig Castellar (Santa Coloma de Gramenet, Barcelona).

Sweden's Viking Age population appears to have suffered from severe oral and maxillofacial disease, sinus and ear infections, osteoarthritis, and much more. This is shown in a study from the University of Gothenburg in which Viking skulls were examined using modern X-ray techniques.