(Opinion) Marijuana Legalization and the Big Tobacco Playbook

Wednesday, April 8, 2020

By: Raja Flores, MD

Since 2014 the number of marijuana users has tripled to 55 million in the United States, according to the latest Marist Poll. The cannabis industry is thriving. Recreational pot is all but certain to be legalized by the new legislature in Albany, New York. Industry lobbyists are elated and I have a sense of dread.

Corporate marijuana has adopted the Big Tobacco playbook using a number of tactics. Advertising suggesting that the product is safe and good for you is the first deception. One ad in a health magazine shows an athletic-looking, pony-tailed young woman running. The caption reads: “Marijuana, organic – tobacco free!” Unreliable and poorly designed studies are being used to prove that marijuana is not harmful. And very artfully, medical marijuana has been used as a Trojan horse for recreational marijuana.

Well-designed studies must follow a large number of well selected subjects, and they must follow them over a long period of time. The selection of subjects is critical—a patient who smoked one joint in their lifetime is of no value scientifically. The time period is equally important—lung cancer often takes many decades of smoking to develop.

In 2017, the National Academy of Medicine gathered a panel of sixteen experts who issued the statement: “There is moderate evidence of no statistical association between cannabis smoking and the incidence of lung cancer.” The studies that this statement was based upon are not reliable because they included people with low marijuana use, were conducted over a too short 3- to 6-year study period and had an insufficient number of subjects.

A well-designed study headed by Dr. Russell C. Callaghan from the University of Northern British Columbia, assessed 49,321 Swedish males for cannabis use and tracked them for forty years. Its conclusion: “Our primary finding provides initial longitudinal evidence that cannabis use might elevate the risk of lung cancer.” The study also yielded the finding that marijuana use was an independent predictor of lung cancer, regardless of cigarette smoking history. This study is ignored by corporate marijuana proponents.

Another study by Dr. David Moir from the Drug Strategy and Controlled Substances Health Program in Canada demonstrates that the same carcinogens that cause lung cancer in the tar of tobacco cigarettes are equivalent to those in the tar from marijuana cigarettes.

The distinction between medical and recreational marijuana is essential. When prescribed properly, medical marijuana can help certain patients. I have recommended it to some of mine.

In my practice, every working day I cut into the cancer-ravaged lungs of patients. The majority were exposed to cigarette smoke in their lifetime. But I am seeing a growing number of lung cancers in marijuana smokers. My fear for the future is a new generation of thoracic surgeons trying to save the lives of a new generation of lung-cancer victims—this time, from cannabis. We must learn from the history of tobacco and slow down the cannabis steamroller.


Dr. Raja M. Flores, is Professor and System Chair of Thoracic Surgery at Mt. Sinai School of Medicine. Flores received a B.A. in biochemistry from New York University, M.D. from Albert Einstein College of Medicine, M.S. in biostatistics from Columbia. His internship and residency at Columbia-Presbyterian Medical Center were followed by a Thoracic Oncology Clinical Research Fellowship in Intraoperative Chemotherapy, Mesothelioma and Lung Cancer at Brigham and Women's Hospital/Dana-Farber Cancer Institute, and a Cardiothoracic Surgery Residency at Harvard Medical School, both in Boston, Massachusetts. He is a Trustee of The Murray Hill Neighborhood Association.