He is the son of Alberto Garzón Blanco, a teacher of Geography and History in Málaga, and Isabel Espinosa Casares, a pharmacist from Cenicero, La Rioja.

[2] In 2004, he participated in the foundation of Students for a Critical Economy, an association of which he was president until 2008, and that was in the same line as the Post-autistic economics movement born in France a few years earlier.

[5] Garzón later earned his Master's in International Economy and Development at the School of Business & Economic Sciences at the Complutense University of Madrid.

[9][needs update] In 2022 Garzón triggered controversy by criticizing factory farming, emphasizing its environmental damage and poor-quality meat exports.

[10] He praised traditional grazing as more sustainable but faced backlash from the meat industry, opposition politicians, and senior members of the ruling Socialist Workers party.

Spain's livestock industry depends on exports, and his comments received a strong negative reaction from various quarters.

[12] A report linked intensive pork farming to an environmental disaster in Spain, which led to the deaths of thousands of fish.