He studied at the Granbery Institute and then joined the Medical School of Rio de Janeiro, where he attended until the third year, when he moved to Berlin, graduating in 1914.

Mello was a member of the Academia Brasileira de Letras and the Brazilian Academy of Medicine.

[4] Mello was the author of the skeptical book Mistérios e Realidades Deste e do Outro Mundo published in Brazil in 1950.

According to a review it is a "very interesting and provocative work... [Mello] disbelieves in the reality of paranormal phenomena and thinks that all can be explained in terms of the known.

In his view psychical researchers are both credulous and gullible and are to be blamed for pandering to human superstition and the widespread hunger for the occult.