Meh.
It prevents the book from being too ghoulish as can happen with true events, but it makes the book much weaker. Hearing what a magazine editor ate at a restaurant while a writer pitched a story in a flashback as the writer is dying of dehydration in the Sahara….nope, nope, nope.

The ACTUAL nonfiction part of the book where physiology is discussed and history is discussed  was interesting(the gin and tonic was invented by the British in India as a more palatable way to take the malarial drug quinine). The made up parts are fairly cringy (the character who catches malaria and dies has hook up sex with a girl from Australia on the night he’s bitten by the mosquito).

I had to read the chapters in fits and starts.
It was interesting enough for me to continue reading and to finish, but there are many better survival books out there.

And as a content warning, the book was written before 2001 and uses the height of the Twin Towers as a comparison of climbing height.