The long-term risks of cannabis use

People who smoke cannabis regularly are more likely to suffer from gum and oral health problems than non-smokers. Their short-term memory may also be affected. An analysis of two long-term studies.

Dr. Madeline H. Meier of the University of Arizona and her team of researchers based their study on 1,037 New Zealanders born between 1972 and 1973. Cannabis use was tracked starting at age 18, and the researchers observed physical health issues once the participants reached age 38. The participants self-reported their cannabis use, which could cast doubt on the accuracy of their reports—particularly regarding the use of other drugs.

Of the 1,037 participants, 484 used tobacco daily, and 675 of them had used cannabis (more than 50% of New Zealanders have used cannabis at some point). The findings reveal surprising and concrete results after 20 years of research: cannabis smokers brush their teeth less often and are more prone to alcohol dependence. This is how periodontal disease develops. Periodontal disease affects the gums and teeth; caused by poor oral hygiene, it typically develops in one’s thirties. Aside from oral health issues, no other medical conditions have been linked to cannabis.

«After 20 years of studying cannabis use, we have not found any physical problems attributable to cannabis,» concludes the »study.

Read more: Side effects of cannabis

Random Access Memory

The American Medical Association has also published a study suggesting that smoking every day could have damage to short-term memory. Professor Reto Auer of the University of Lausanne leads a team of researchers studying data from 3,400 Americans over 25 years. During those 25 years, the test subjects undergo a series of cognitive tests.

«In February, another study showed that after 5 years of regular smoking, verbal and lexical memory abilities were lower than those of nonsmokers or occasional smokers.»

This conclusion is linked to other factors that affect the cognitive system: education, age, the use of other drugs, and depression. Dr. Auer also coined a new unit of measurement: ’marijuana-years.« If you smoke every day, one »marijuana-year« will pass; if you smoke once a week, it will take you 7 years to reach one »marijuana-year.«.

The more a guinea pig smokes, the worse its performance on cognitive tests.

Read more: The health effects of cannabis

How a cognitive test is conducted: Two groups of 10; each person is given 15 words, and 25 minutes later, the test subject must recall the words with as many similarities as possible.

Non-smoking patients recall 9 out of 15 words In general, people with at least 5 «marijuana years» come out on top. 8.5 out of 15.

The results aren't all that concerning at this stage, but the gap widens among older patients. At age 45, those who smoke ganja recall 2.5 fewer words than non-smokers. Of the 3,385 participants in the study, only 8 % (311) had more than 5 «marijuana years.».

On the other hand, concentration, reaction speed, and logical problem-solving do not seem to not affected through daily cannabis use.

Conclusions: If you smoke more than just occasionally, the U.S. Public Health Service recommends that you exercise your working memory and brush your teeth thoroughly!

Caillart Théo