The AIDE project, led by Rozenn Colleter, an archaeo-anthropologist at Inrap and an associate researcher at UMR 5288 of CNRS, is exploring the diets of ancient populations by analyzing amino acids from stable isotopes of carbon and nitrogen found in archaeological skeletons. This research aims to identify dietary patterns and uncover potential social inequalities in the past. The project is funded by the Horizon 2020 research and innovation program of the European Union, under the Marie Skłodowska-Curie grant agreement number 897565. In recent years, social scientists have increasingly recognized that economic and social conditions significantly influence health throughout a person's life. The World Health Organization (WHO) Health Center highlighted this connection in the early 21st century, drawing attention to how social factors determine health outcomes. Social inequalities, shaped by lifestyle and position in society, affect health status unevenly. For instance, in France, managers live about six years longer than workers, and this gap widens to ten years when considering life expectancy without disability. Those at the lower end of the social scale are at least twice as likely to face serious illness or premature death compared to those at the top. These patterns of inequality are not unique to modern times. Archaeologists and anthropologists have long debated similar issues in ancient populations. Since diet and health are closely linked to an individual's economic and social environment, the study of ancient skeletal remains provides valuable insights into past inequalities. In France, the growth of preventive archaeology has led to the discovery of thousands of human skeletons each year, offering a unique opportunity to understand ancient lifestyles through physical evidence. By comparing osteometric observations, pathological findings, and isotopic analyses of bones, researchers can assess the health of ancient societies and formulate hypotheses about the inequalities they faced. Differences in burial practices also reflect social status, such as the burial of Louise de Quengo, an aristocrat interred in a lead coffin in 1656 at a convent in Rennes, and a child from the early Middle Ages found at the edge of a necropolis in Olonne-sur-Mer. The AIDE project aims to determine if dietary markers derived from isotopic analysis can effectively reveal inequalities across different historical periods and cultural contexts. For more information, visit https://archeoinega.hypotheses.org.