He has a background in family practice and a special interest in childhood development, trauma[1] and potential lifelong impacts on physical and mental health, including autoimmune disease, cancer, attention deficit hyperactivity disorder (ADHD),[2] and addictions.

[9] After working as a high school English and literature teacher for several years, he returned to the University of British Columbia to obtain his M.D.

[11] In 2008, Maté made national headlines in defence of the physicians working at Insite (a legally supervised safe injection site) after the federal Minister of Health, Tony Clement, attacked them as unethical.

Although preliminary and limited by the observational study design, the research results showed that participants had significant improvements in some psychological measures and reductions in problematic substance use, suggesting that Maté's claims of therapeutic efficacy may be well-founded.

[13] However, when the Canadian federal government learned about Maté's work with ayahuasca in 2011, Health Canada threatened to refer the matter to the RCMP if he did not immediately stop his activities with an illegal drug.

By this definition, many things in modern culture have the potential to become addictive such as gambling, sex, food, work, social media, and drugs.

[11] He says a system that marginalizes, ostracizes, and institutionalizes people in facilities with no care and easy access to drugs, only worsens the problem.

"[18] Peele, in general, disagrees with the theory adopted decades ago by modern physicians, mental health professionals, research scientists, and others, that addiction is a disease[19][20][21] and opposes all twelve-step drug and alcohol treatment programs.

During the chat, Maté told Prince Harry that he had diagnosed him with ADD after reading through his book and hearing about his life experiences.

[28] Maté drew direct comparisons between Gaza and the Warsaw Ghetto and commented on the severe power imbalance: "Unlike Israel, Palestinians lack Apache helicopters, guided drones, jet fighters with bombs, laser-guided artillery.