It is incredible (in the strict sense: hard to believe) to discover that many foods are "fake", or contain things that are not supposed to be there.

I suggest a few readings:

0) the book "Real Food / Fake Food" [0]. This is just amazing. Highly recommend it.

1) the book "extra virginity" [1]

2) article about "truffle fraud" [2]

3) article about "fish fraud" [3]

The list could be almost infinite, of course.

[0]: https://www.amazon.com/Real-Food-Fake-Youre-Eating/dp/161620...

[1]: https://www.amazon.com/Extra-Virginity-Sublime-Scandalous-Wo...

[2]: https://www.eater.com/2019/5/28/18638762/truffle-fraud-fake-...

[3]: https://www.theguardian.com/environment/2021/mar/15/revealed...

"Good" olive oil enjoys a really healthy process, as opposed to most "new" oils available commercially only in recent years.

However, there is a lot of "fake" or altered olive oil in circulation. Be well aware of this. [0] [1]

[0]: https://www.forbes.com/sites/ceciliarodriguez/2016/02/10/the...

[1]: https://www.amazon.com/Extra-Virginity-Sublime-Scandalous-Wo...