Both smoking and eating cannabis caused the blood vessel linings to not work as effectively, even in otherwise healthy adults who never used tobacco, researchers at the University of California, San Francisco (UCSF) found.
"The blood vessels don’t seem to care whether the smoke is from tobacco or cannabis," study author Matthew L. Springer, professor of medicine at the Cardiovascular Research Institute at UCSF, told The Epoch Times. The research shows cannabis users had blood vessel function "very similar" to tobacco smokers in previous studies, he noted.
Different Methods, Same Damage
For the estimated 17.7 million Americans who use marijuana in some form every day, according to polling data, the study raises important questions about long-term health risks that remain largely unstudied.
The research, recently published in JAMA Cardiology, tracked 55 healthy adults aged 18 to 50, dividing them into three groups: marijuana smokers, THC (Tetrahydrocannabinol) edible users, and non-users. All cannabis users consumed their preferred method at least three times weekly for more than a year—making them regular, not casual users.
Springer said they had a good reason for the relatively small number of participants. "We were very picky!"
"The study is very clean in that our cannabis user groups have never been tobacco smokers/vapers, and tend to avoid secondhand smoke," he added. "The marijuana smokers only smoke marijuana and don’t vaporize it or vape THC, and our THC edibles group avoids all smoke."
Researchers measured blood flow-mediated dilation, which shows how well blood vessels relax and contract. Both cannabis groups showed significantly worse vascular function than nonusers, with heavier use linked to greater damage.