The aim of this study was to analyse the occurrence and pace of secular trends regarding body proportions among young adults representing different place of origin, studying in Bydgoszcz (Poland). The data constituted of the results of anthropometric measurements of 1,199 young adults (340 male and 859 female) performed between 2001 and 2019. Selected body build parameters were measured and the following indices were calculated on their basis: upper-limb index, lower-limb index, inter-limb index, chest depth-to-breadth ratio, pelvi-acromial index, reciprocal ponderal index. The place of origin was self-reported by the participants and recorded by the researchers. Based on that piece of information the participants were divided into two categories: villages and small cities, big cities. Considering the pace of the changes, they occurred the fastest for the pelvi-acromial index and the slowest in the case of the lower limb index, which concerned both urbanisation categories. Between 2001-05 and 2016-19 analysed changes generally occurred faster in the high-urbanisation category than in the low-urbanisation one, except for chest depth-to-breadth ratio and lower limb index in male participants as well as reciprocal-ponderal index and pelvi-acromial index among women. In conclusion, obtained results allow observing the changes in selected body proportions occurring over the years 2001-2019 in the population of young adults from Poland. Additionally, the findings can help identify and address risk factors related to specific proportions of the body and present in the contemporary population.