Study examines cannabis and IQ

One of the main arguments of opponents of legal marijuana is that underage use is increasing and that it is harmful to children. Everyone agrees, but the same applies to nicotine and alcohol, i.e. age limits. Although the argument that the number of minors is increasing has been debunked, there are still concerns about the impact of a still-developing brain. No one in the industry is advocating that a 10 year old smoke, just as no one is advocating serving a 10 year old a whiskey sour. But is someone who starts using at the age of 24 affected? Well, a study looks at cannabis and IQ.

A large study in New Zealand found that persistent marijuana use disorder, with frequent use starting in adolescence, was associated with a loss of an average of 6 or up to 8 IQ points measured in middle adulthood.43 Those who used marijuana heavily as teenagers and When used as adults, the lost IQ points could not be restored. People who began heavy marijuana use in adulthood did not lose IQ points.

An earlier study in 2001 published in the journal Archives of General Psychiatry found that “the former marijuana smokers did not exhibit cognitive impairment,” as did a study published four years later in the journal Neurotoxicology and Teratology.

A study conducted in 2001 and published in the journal Archives of General Psychiatry found that “the former marijuana smokers had no cognitive impairment,” as did a study published four years later in the journal Neurotoxicology and Teratology.

At the other end of the spectrum are studies that suggest the opposite. Usually like that Studies focus primarily on the long-term outcomes of those who began using marijuana earlier in life and compare statistically significant changes in cognitive function between those who use cannabis and those who do not.

The New Zealand study followed 1,037 New Zealanders aged 3 to 45 to determine the effects of marijuana on brain function. The study, published in the American Journal of Psychiatry, found that those who used cannabis early, long-term and regularly did experience cognitive impairment.

In addition to a 5.5 point decline in users’ IQ from childhood to midlife, the results confirmed some deficits in learning and processing speed compared to those who are not marijuana users.

RELATED: Science Says Medical Marijuana Improves Quality of Life

An important note, as with alcohol, is that long-term cannabis users also developed memory and attention problems, the study found. And like alcohol and nicotine, using marijuana at an early age can have long-term negative effects. More research needs to be done regarding adult use.