• The δ 13 C and δ 15 N values suggest a diet mainly based on beef. • Modeling in FRUITS indicates that fish accounted for ∼15–24% of animal protein. • Consumption of fish did not decline after the Lutheran Reformation in 1527. • Females had a less varied diet than males, and males had greater access to fish. • After the Reformation, dietary differences between males and females became more pronounced. This study employs an interdisciplinary approach to investigate diet at the Swedish town of Nya Lödöse (1473–1624 CE). The primary aim is to determine the proportions of aquatic and terrestrial foods consumed in the diet and to examine whether these proportions shifted after the Reformation in 1527. A secondary aim is to analyze variations in diet related to biological sex or social status. δ 13 C and δ 15 N stable isotope ratio analysis of bulk rib collagen from humans (n = 71) and fauna (n = 202) was conducted, and the results show the sampled individuals have similar isotopic compositions, with mean δ 13 C values of −19.9 ± 0.7‰ and δ 15 N values of 12.6 ± 1.0‰. These isotopic values suggest a diet rich in animal protein, mainly beef, with some consumption of aquatic resources. The Bayesian mixing model FRUITS was used to estimate the relative consumption of livestock, marine fish, and freshwater/pelagic fish. Modelling indicates an average aquatic protein intake of ∼ 15–16% for females and ∼ 20–24% for males. Comparing isotopic data from before and after the Reformation reveals no major changes in diet, although the post-Reformation period saw a small increase in fish intake in males and a diversification in diet in both sexes. The isotopic data suggest a slight but statistically significant difference in diet between males and females. Females had a less varied diet than males, with males having greater access to fish. After the Reformation, dietary differences between the sexes became marginally more pronounced.
Maltin et al. (Thu,) studied this question.