What you need to know
The number of Americans is rising at record levels. As more people use marijuana, there is increasing evidence that marijuana may be linked to certain heart problems. It’s unclear whether the heart risks arise from smoking marijuana or whether the THC in weed could be harmful.
About one in five people over the age of 12, an estimated 61.9 people in the U.S., have used marijuana in the past year, up from 52.5 million the year before, according to data released Nov. 13 from the National Survey on Drug Use and Health. As more states legalize recreational use, cannabis is certainly the most popular mind-altering drug in the USA
It is so widely viewed as safe that a recent Pew Research poll found that 9 in 10 Americans believe it Marijuana should be legal for both medical and recreational use.
However, recent studies have found links between marijuana use and cardiovascular problems, including cardiac arrhythmias and even heart attacks. While some of the results are contradictory – some see a risk of heart failure, others do not – and no definitive conclusions can be drawn about marijuana’s risk to the heart, researchers say the signs should not be ignored.
Earlier this month, the American Heart Association presented preliminary results from two studies that found marijuana use was associated with a higher risk of heart attack and heart failure.
The results of the first studyThe study looked at people with an average age of 54 and found that the risk of heart failure was 34% higher in people who used marijuana daily than in those who had never used it.
In the second study, researchers analyzed patients who were hospitalized for any reason and found that people who used marijuana and had a disease such as type 2 diabetes had a significantly increased risk of heart attack compared to people who Cardiac arrest or cardiac arrhythmias occurred in patients who did not use cannabis.
“I’m very worried,” said Robert Page, a clinical pharmacist who specializes in heart disease at the University of Colorado Skaggs School of Pharmacy. “It appears that cannabis may be a risk factor for the development of cardiovascular disease.”
Dr. Peter Grinspoon, one of the leading cannabis researchers in the United States, said that while it was important to note that the two studies do not directly prove that marijuana causes heart problems, it is an issue that urgently needs to be studied.
“We definitely need to explore this much more comprehensively,” said Grinspoon, a family physician at Massachusetts General Hospital and an instructor at Harvard Medical School. “It’s important that we find out.”
Is using marijuana bad for my heart?
Early findings from a large Danish study Last year, medical marijuana use for chronic pain was found to be associated with a 64% increased risk of heart arrhythmias such as atrial fibrillation, which can increase the risk of stroke or death. The examination did not reveal an increased risk of heart failure.
THC, the active ingredient in cannabis that gets people high, could affect the heart by activating the sympathetic nervous system, our body’s fight-or-flight response. This can lead to increased heart rate and blood pressure, putting more strain on the heart.
“Anything that can increase your heart rate can cause heart attacks and possibly heart failure,” Grinspoon said.
Page, the lead author of a comprehensive opinion A report on cannabis published by the American Heart Association in 2020 wrote that cannabis may have some therapeutic benefits, but not for the heart.
“At this point, there are no cardiovascular benefits to any form of cannabis,” he said. “It’s just not there in my head.”
Is it the smoke or the weed?
This is where the science gets really murky. Because it can take years to conduct scientific research and evaluate the results, cannabis studies are typically conducted on older forms of marijuana that are far less effective than those available today. The potency of cannabis – measured by the THC content in the product – has been increasing for nearly half a century, increasing by about 0.29% each year from 1970 to 2017.
Although most studies have looked at people who smoke marijuana, more data is needed, Grinspoon said. His best guess is that it’s the smoke — which contains the same carcinogens and tar as tobacco cigarettes — and not marijuana itself that could be damaging our hearts.
“It’s certainly not as bad as tobacco smoke, which kills 480,000 people a year,” Grinspoon said. “But cannabis smoke contains cyclic aromatic hydrocarbons, and these are things that you can’t even say are good for the heart.” Cyclic aromatic hydrocarbons are chemicals that are produced when tobacco, coal, oil, gas, wood are burned and waste are created and damage the DNA.
While vaping can mitigate some of smoke’s toxic chemicals, it is not without risk, Dr. Robert Kloner, cardiologist and chief scientific officer at the Huntington Medical Research Institutes in Pasadena, California.
“Vaping may be safer than smoking because you don’t inhale the tar or carbon monoxide associated with smoking,” he said.
Ultimately, it depends more on the dose taken.
“If you take a hit once a week at a party, it’s not going to make much of a difference to your heart,” Grinspoon said. “But if you smoke a vape pen 30 times a day, that’s obviously bad for your heart.”
Is food safe?
Little is known about cannabis edibles such as gummies, chocolate, candies, brownies or drinks, Page said. While the number of children poisoned by accidentally consuming marijuana edibles has skyrocketed, there is “very limited data” about what they do to the body, Page said.
It’s plausible that edibles are less risky because no smoke is inhaled. “If you can use a tincture or an edible, you won’t get any of the inhaled combustion products that are particularly harmful to your heart and can lead to hardened arteries,” Grinspoon said.
Here too, it depends on the dose.
“If you take half a gummy bear or 2.5 milligrams and fall asleep, it’s very unlikely that you have coronary heart disease,” Grinspoon said.
Who is at risk?
People with coronary heart disease, hardening of the arteries or a family history of heart disease should be careful.
“If they had a heart attack six weeks ago, I wouldn’t start cannabis,” Grinspoon said. “I would be very, very cautious unless there was incredibly compelling evidence,” he added, referring to patients using it for medical purposes.
When arterial disease causes the heart to beat faster and require more oxygen because THC activates the fight-or-flight response, this can cause problems.
“You get kind of a double whammy,” he said. “This can lead to a heart attack.”
Even young people who may not know whether they have high cholesterol or high blood pressure – conditions that put them at higher risk of heart disease – need to be careful.
“They think they are invincible and [then] They consume a cannabis product and boom, they might host an event,” Page said.
