The research, published Friday in the journal Cell, looked at more than 11,000 people between ages 40 and 69 who said they smoked marijuana at least once a month. The scientists then compared that group to 122,000 other people in the same age bracket who did not smoke marijuana at all, and nearly 23,000 more who smoked less frequently.
The study authors controlled for age, gender and body mass index — three factors that influence the risk of heart disease — and found that people who smoked marijuana frequently were more likely than people who did not to have a first heart attack before age 50. Having one heart attack increases the lifelong risk of having another or developing heart failure.
The findings align with other similar research. The Centers for Disease Control and Prevention already warns that smoking marijuana could lead to an increased risk of heart disease, and a 2021 study identified an association between heart attacks and marijuana use in young adults. But the new study goes a step further, since it also attempts to figure out why smoking weed can lead to heart problems.
To investigate that, the researchers studied how THC affects both human stem cells and mice stem cells. It's already known that when people smoke marijuana, THC binds with a receptor in the brain, which is what gives the feeling of being high. In their lab studies, the team found that THC also binds to that receptor in blood vessels.
So the researchers suggested that using THC frequently could activate that receptor in a way that leads to inflammation in blood vessels, which in turn can accelerate a buildup of plaque in the arteries that can lead to a heart attack. READ MORE...
