How long has pizza been part of the Italian diet?

It's difficult to pinpoint the exact moment pizza became part of the Italian diet, but here's what we know:

* Origins in Naples: Pizza's origins are firmly rooted in Naples, Italy. It likely emerged as a simple, affordable food for the working class in the 18th century.

* Popularity in the 19th century: By the mid-19th century, pizza started gaining popularity among various social classes in Naples. It was even documented by writers and artists of the time.

* National recognition: The late 19th and early 20th centuries saw pizza spread beyond Naples and become a national food. This was fueled by several factors:

* The rise of Neapolitan immigrants who brought their food traditions to other parts of Italy and the world.

* The popularity of pizza among Italian soldiers during World War I, who brought it back to their families after the war.

* The growing appreciation for regional Italian cuisine in the 20th century.

Therefore, while pizza's origins are in the 18th century, it became a significant part of the Italian diet in the 19th century, becoming a national symbol of Italian cuisine in the 20th century.

It's important to note that while pizza is a staple food in Italy, its popularity varies regionally. It's most deeply ingrained in Naples, where it originated, but it is widely enjoyed throughout the country.