The peasant diet during the Little Ice Age in Sweden was mainly grain-based (bread, gruel, and porridge), and the country was heavily dependent on grain imports to meet the population’s needs for food. During the eighteenth century in particular, when famines were frequent following failed harvests, Swedish peasants utilized a range of locally available resources to survive. Bark bread made of cambium (phloem) from Pinus sylvestris was, for example, commonly used as famine food. Scientists of the Enlightenment period and the state authorities tried to alleviate hunger and poverty through the introduction of new food resources and cooking techniques, including wild or agricultural plants such as lichens or potato, and the use of protein sources different from the traditional ones, such as horse meat. However, many of these proposals encountered strong resistance from the peasantry, and only at the end of the 1800s famines ceased to cause suffering in Sweden. Scientific studies have so far focused mainly on mortality, malnutrition, demography, and official responses to famines; yet the question of what the starving peasants gathered, prepared, and consumed is important for the understanding of the historical situation. Also, the difference between the scientific proposals and peasants’ decisions and choices must be clearly distinguished. This historical study using an ethnobiological approach discusses peasant subsistence strategies in Sweden in the eighteenth century using contemporary sources, which provide an opportunity to study how the population obtained foodstuffs, adapted their diet to available ingredients, and the interaction and conflicting views of peasants and scientists about new, science-based nutrition proposals. Keywords: emergency food; food security; gastronomic ethnobiology; hunger; subsistence crisis.