How early were low calorie foods (celery, cucumbers, lettuce, etc...) cultivated, and did they know the crops provided little energy to the body? | AskHistorians Archive Observer

How early were low calorie foods (celery, cucumbers, lettuce, etc...) cultivated, and did they know the crops provided little energy to the body?

by Affordable_Z_Jobs

It seems counter intuitive to devote time and energy to crops that don't offer a lot of bang for their buck.

Celios

On a similar note, why did Shirataki noodles remain popular in Japan, when these are a zero calorie food? Isn't this strange, considering Japan has relatively little arable land?