Many plant remains such as seeds and nutshells are found from the Jomon sites. How many plants did people in the Jomon period take for a daily food?
It was frequent to eat plants in the raw or by cooking. Ancient alcoholic beverage is suggested from seed remains such as grape (Vitis coignetiae) and elderberry (Sambucus racemosa subsp. sieboldiana). It seems to have been preservative food by drying in the sun.
Daily values of Jomon people were followed by environments around sites and seasons, and thus how much quantity of plant foods did Jomon people take in a day?
Scientific analyses of human bones might answer my question. I'm very interested in this.
Here is a leaflet describing food in the Jomon period which I made a track back.