CHICAGO — New analysis suggests legalizing leisure marijuana for U.S. adults in some states could have barely lowered teenagers’ odds of utilizing pot.

One cause could also be that it’s tougher and costlier for teenagers to purchase marijuana from licensed dispensaries than from sellers, stated lead creator Mark Anderson, a well being economist at Montana State College.

The researchers analyzed nationwide youth well being and conduct surveys from 1993 by means of 2017 that included questions on marijuana use. Responses from 1.four million highschool college students have been included.

Thirty-three states have handed medical marijuana legal guidelines and 11 have legalized leisure use — usually for ages 21 and up, many through the research years. The researchers checked out total adjustments nationwide, however not at particular person states.

There was no change linked with medical marijuana laws however odds of teenybopper use declined nearly 10% after leisure marijuana legal guidelines have been enacted.

The research was revealed Monday in JAMA Pediatrics.

Earlier analysis has discovered no impact on teen use from medical marijuana legal guidelines, and conflicting outcomes from leisure marijuana legal guidelines. The brand new outcomes echo a research exhibiting a decline in teen use after gross sales of leisure pot started in 2014 in Washington state.

The outcomes “ought to assist to quell some considerations that use amongst teenagers will really go up. This is a vital piece when weighing the prices and advantages of legalization,” Anderson stated.

About 20% of U.S. highschool college students use marijuana, unchanged since 2015 after an earlier decline, based on the 2017 model of the surveys used within the research. Charges ranged from 13% of ninth graders to 26% of highschool seniors, based on the survey knowledge from the federal Facilities for Illness Management and Prevention.

“Repeated marijuana use throughout adolescence could result in long-lasting adjustments in mind operate,” authors of the brand new research wrote. Within the short-term, it may well trigger impaired reminiscence and a spotlight issues lasting weeks. Frequent use beginning within the early teenagers could decrease IQ scores; some youngsters could also be extra susceptible to pots’ results due to genetics or different components.

The Related Press Well being and Science Division receives help from the Howard Hughes Medical Institute’s Division of Science Training. The AP is solely chargeable for all content material.