Review Article Volume 17 Issue 11 - 2025

Early Cannabis Use Poses Risks to Physical and Mental Health: Delayed Use/Non Use Encouraged

Kenneth Blum1-4*, Kai-Uwe Lewandrowski4,5, Alireza Sharafshah6, Kyriaki K Thanos7, Abdalla Bowirrat2, Albert Pinhasov2, Igor Elman2,8, Marco Lindeau1, Álvaro Dowling9,10, Rafaela Dowling11, Joao Paulo Bergamaschi1, Rossano Kepler Alvim Fiorelli4, Sérgio Luís Schimidt4, Rajendra D Badgaiyan1,12, Morgan P Lorio13, Debasis Bagchi14, David Baron15,16, Edward J Modestino17, Brian Fuehrlein18, Kavya Mohankumar19 and Mark S Gold16

1The Kenneth Blum Behavioral and Neurogenetic Institute, Austin, TX, USA

2Department of Molecular Biology, Adelson School of Medicine, Ariel University, Ariel, Israel

3Department of Psychiatry, University of Vermont, School of Medicine, Burlington, VT, USA

4Programa de Pós-Graduação em Neurologia, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, Brazil

5Department of Orthopedics, University of Arizona, Banner Medical Center, Tucson, Arizona, USA

6Cellular and Molecular Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran

7Department of Psychiatry, University of Buffalo, Buffalo, NY, USA

8Department of Psychiatry and Cambridge Health Alliance, Harvard Medical School, Cambridge, MA, USA

9Orthopaedic Spine Surgeon, Director of Endoscopic Spine Clinic, Santiago, Chile

10Department of Orthopaedic Surgery, USP, Ribeirão Preto, Brazil

11Catacell, Santiago de Chile, Chile

12Department of Psychiatry, University of Texas Long School of Medicine, Health Science Center, SAN Antonio, TX, USA

13Department of Osteopathic Principles and Practice, Orlando College of Osteopathic Medicine, Orlando, FL, USA

14Department of Pharmaceutical Sciences, Texas Southern University College of Pharmacy, Houston, TX, USA

15Division of Addiction Research and Education, Center for Sports, Exercise, and Mental Health, Western University of Health Sciences, Pomona, USA

16Department of Psychiatry, Stanford University School of Medicine, Palo Alto, USA

17Department of Psychology, Curry College, Milton, USA

18Department of Psychiatry, Yale University, New Haven, USA

19Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA

*Corresponding Author: Kenneth Blum, The Kenneth Blum Behavioral and Neurogenetic Institute, Austin, TX, USA.
Received: November 10, 2025; Published: December 02, 2025



Key Points

  • Early teen cannabis use correlates with higher use of mental and physical health services in young adulthood.
  • Teens who use cannabis early have more injuries, poisoning, respiratory, and other problems than abstainers.
  • Five years of data show that the best advice on teen use of cannabis is: Don't use. Next best: Delay use.

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Kenneth Blum., et al. “Early Cannabis Use Poses Risks to Physical and Mental Health: Delayed Use/Non Use Encouraged”. EC Neurology  17.12 (2025): 01-08.