Fungi have played a significant role in human diets, yet their presence in archaeological contexts remains underexplored. Evidence of mushroom consumption has been found in human dental calculus, tombs, and sacks found in burrial grounds [1,2,3]. This study investigates whether stable isotope analysis can reveal fungal contributions to past diets, focusing on Lithuania, where mushroom foraging is a long-standing cultural tradition.
By synthesizing data from the literature and our analyses, we explore the isotopic variability of fungi and its implications for dietary reconstructions while considering the soil in which the mushrooms grew. Our findings indicate that fungi exhibit highly variable carbon and nitrogen isotope values, which can complicate traditional interpretations of nutritional sources. Notably, substantial mushroom ingestion may contribute to isotopic signatures resembling those of high meat consumption. This effect is particularly relevant in archaeological human and animal remains displaying ‘terrestrial’ carbon isotope ratios and elevated nitrogen isotope values.
Given Lithuania’s deep-rooted history of mushroom foraging, our research highlights the importance of considering fungi as a dietary factor in stable isotope studies. Factoring fungi into these studies will provide us with a better understanding of what people ate in the past and how their surroundings influenced their diets. Great thanks to dr. Olga Jefanova and prof. habil. dr. Jonas Mažeika from the Laboratory of Nuclear Geophysics and Radioecology, Nature Research Centre, for the mushroom sample lyophilization.