How much sugar is required per day for a person?

Answer 1

There is no need for sugar in the diet.

Crystalline sugar was not available in Europe until about 1100 AD. Even after becoming available it was expensive and only available to the wealthy. It was only since the sugar plantations of the Americas (300-400 years ago) that sugar became part of the diet of ordinary people.

In summary, people only began eating sugar in fairly modern times. They did not have it for hundreds of thousands of years