Marijuana use and heart-attack risk were correlated in a large human study, Stanford scientists and their collaborators found. A molecule in soybeans may counteract these effects.
April 29, 2022 – By Krista Conger
People who smoke marijuana more than once a month have an increased risk of heart attack and heart disease, Stanford researchers and their colleagues have found.
People who use marijuana have an increased risk of heart disease and heart attack, according to a large study led by researchers at Stanford Medicine.
The study also showed that the psychoactive component of the drug, known as THC, causes inflammation in endothelial cells that line the interior of blood vessels, as well as atherosclerosis in laboratory mice.
The inflammation and atherosclerosis can be blocked by a small molecule called genistein that occurs naturally in soy and fava beans, the researchers found. Because genistein has limited brain penetration, it doesn’t inhibit THC’s ability to stimulate appetite, dull pain and tamp down nausea — characteristics vital to medicinal marijuana users.
“As more states legalize the recreational use of marijuana, users need to be aware that it could have cardiovascular side effects,” said Joseph Wu, MD, PhD, professor of cardiovascular medicine and of radiology, and the director of the Stanford Cardiovascular Institute. “But genistein works quite well to mitigate marijuana-induced damage of the endothelial vessels without blocking the effects marijuana has on the central nervous system, and it could be a way for medical marijuana users to protect themselves from a cardiovascular standpoint.”
In part because THC, or tetrahydrocannabinol, is a controlled substance in the United States and therefore strictly regulated in medical research, the investigators cautioned that the long-term health effects of regular use remain largely unclear.
“Marijuana has a significantly adverse effect on the cardiovascular system,” said instructor of medicine Mark Chandy, MD, PhD. “As more states legalize marijuana use, I expect we will begin to see a rise in heart attacks and strokes in the coming years. Our studies of human cells and mice clearly outline how THC exposure initiates a damaging molecular cascade in the blood vessels. It’s not a benign drug.”