SoylentNews

hubie writes:

The diet and eating habits of earlier civilizations has been inferred from old manuscripts and artwork, but there is always a question as to how representative that is of what the common diet was at the time, in much the same way as whether in a millennia from now one could infer our modern-day diet from surviving ``foodie'' magazines. It is always a bonus when you can have access to direct tissue to analyze. In a recent paper in the Open Access journal Nature Scientific Reports, Atsushi Maruyama and colleagues in Japan acquired a number of book sets produced during the Edo period and they analyzed samples of human hair found in the books. By analyzing the abundances of various carbon and nitrogen isotopes they were able to make inferences about the early Japanese diet.

The covers of such books are made of recycled thick paper, which, for financial reasons, was believed to have been produced soon before book printing, using waste paper collected in the same cities where the books were printed. Because the hairs are embedded in the paper fibres, the hairs are thought to have been mixed accidentally during waste paper collection or blended intentionally for reinforcement during paper production. In either case, the hairs most likely belong to people living in the city and year of book printing, both of which are available from the records (colophon) on the book. Thus, the hairs found in each book, together with the records of time and place, constitute the ideal human tissue samples to reconstruct the eating habits at the time and place of the book printing, using isotope analysis.

They found that people depended upon rice, vegetables, and fish more exclusively than contemporary Japanese people. They also noticed that the levels of nitrogen increased over 200 years, indicating an increase in the contribution of marine fish as both food and fertilizer, which generally confirms what literature-based studies have found.

Atsushi Maruyama, Jun'ichiro Takemura, Hayato Sawada, Takaaki Kaneko, Yukihiro Kohmatsu & Atsushi Iriguchi, Hairs in old books isotopically reconstruct the eating habits of early modern Japan, Scientific Reports volume 8, Article number: 12152 (2018)

Original Submission