Marijuana, now most often called cannabis, use is growing. In recent years, almost 20% of the U.S. population have used cannabis, with 4% using it daily or almost daily. What is the impact on the health of regular users?
Advocates describe better sleep, less pain, and less anxiety. Unfortunately, these benefits come at a price.
Multiple studies have examined the association of regular cannabis use with symptoms and illness.
I can get the good news out of the way quickly. Regular users are less likely to report nasal congestion than non-users, unlike tobacco users who report more nasal and sinus issues.
Unfortunately, on the key major illness side, the news is not good. Regular cannabis users have more heart attacks and strokes than non-users, with even higher risk among those who use it daily or near-daily.
Regular cannabis smokers also have dramatically more (3-4 times) head and neck cancers than non-users. The highest risk was for laryngeal cancer, but higher rates of mouth and tongue cancer are also seen.
Middle-aged and older adults are increasingly using cannabis-based therapies (CBT) for symptoms, and this population suffers from many CBT-related side effects, including dry mouth, dizziness, balance problems, drowsiness, and confusion.
Motor vehicle accident rates rose an average of 15% in states after recreational cannabis use was legalized, and the best evidence we have suggests that regular cannabis use is associated with a roughly 50% greater chance of having an accident and a 30% increase in fatal accidents.
Finally, there is the concern about cannabis’ effects on the developing brain. Cannabis use by mothers during pregnancy has been linked to problems with attention, memory, problem-solving skills, and behavior in their children.
Using cannabis before age 18 may affect how the brain builds connections for functions like attention, memory, and learning.
So, no, cannabis is not harmless. If you use it, do so with the knowledge that you may pay a price beyond the cost of the drug.
Edward Hoffer MD is Associate Professor of Medicine, part-time, at Harvard.
What Does The Doctor Say?
By Dr. Edward Hoffer