There has always been so much controversy about the harms of marijuana use. However, it is hard to argue with the facts and a recent study indicated that when kids frequently use marijuana before the age of 18 it may cause irreversible harm to their intelligence, attention and memory. In fact, according to researchers at Duke University, people in their middle age that began using marijuana in their teens had a declining IQ score of about 8 points and that deficit was irreversible.
The study out of Duke also concluded that when people waited to smoke marijuana until adulthood they did not show a cognitive decline. The reason is that their brains were already fully developed. This research is fully supported by the published journal from Proceedings of the National Academy of Sciences. The claim is that heavy marijuana use damages the brain.
Marijuana Lowers IQ Scores
This long term study included more than 1,037 children born in 1972 or 1973 in Dunedin, New Zealand from birth to age 38. 5% of those in the study were dependent on marijuana or used it at least one time per week before they were 18. At the age of 38, every individual in the study was assessed on their memory, processing speed, reasoning and visual processing. Those who used marijuana often scored much lower on the tests.
Some have indicated that they are not too worried about a meager 8 points but when the scale only goes to 100 for an average, this drops a person from the 50th percentile to the 29th percentile and that is significant, especially when IQ has so much to do with the quality of life that an individual has or will have. Generally, those with higher IQs are better educated which results in an overall better life.
Those closest to the contributors, who regularly used marijuana as teens, claimed that they noticed a cognitive decline in these individuals. These deficits included memory impairment, attention problems, trouble focusing, and forgetfulness. The lead researcher of this study, Madeline Meier said that marijuana is not a harmless drug, especially where teens are concerned. If you know a child or teen that often smokes marijuana, educate them on the effects that it has on their brain and get them help today.