The Neolithic period in Europe was subject to marked climatic variations during the fourth millennium BCE in the Alpine arc, marking the transition between the recent Atlantic and the Subboreal. This phase is characterized by falling temperatures and rising humidity in the Northern Hemisphere. Within this phase, between 3700 and 3250 BCE, a more intense phase takes place, known as Rootmoos 2 or Piora 2. This phase is characterized by a significant drop in lake water levels. This climatic change had repercussions on lakeside dwellers, notably through the modification and adaptation of their diet and subsistence modes. Intestinal parasites (helminths), found by human and animals via parasitic markers, seem to respond over time to these climatic variations. At first sight, low lake level phases are characterized by significant proportions of Trichuris at the expense of Diphyllobothrium, as well as an increase in Fasciola. These phases therefore seem to favour parasites indicative of agropastoral activities. During periods of high lake levels, Diphyllobothrium increase in number, pointing to a higher frequency of fishing practices. In sum, during periods of cooler/wetter climate, Neolithic lakeside populations seem to focus more on fishing produce, which may be a response to a destabilization of previously established agropastoral systems, marking a return to more opportunistic behaviour with the exploitation of products from the direct environment. This pilot study tends to evaluate if the evolution of parasitic communities in the 4th millennium BCE could therefore be used to complete our understanding of the effects of climatic variations on societies, both as a direct consequence of environmental destabilization (effect on the hosts) and the result of the behavioural adaptation of the inhabitants, even if it is still difficult to determine the importance of the influence of each factor on these variations. Despite some remaining challenges in the current study, the integration of paleoparasitic data into broader paleoenvironmental models appears promising. Future research can continue to develop along this path. •Compilation of all the available data for lacustrine sites dated for the 4th millennium BCE and from Central Europe lake-dwelling area.•Application of the seriograph method and a novel index to analyse intestinal parasitic spectrum diversity.•Evaluation of the intestinal parasitic spectrum response to climate variations and human opportunistic behaviour.