The National Institute on Drug Abuse has surveyed and compiled 11 scientific research studies that have demonstrated that heavy marijuana use, defined as smoking marijuana 27 days in the past 30 days, has a significant impact on users' ability to learn, remember what they learned and function in society.
Effects of Heavy Marijuana UseAccording to these researchers, heavy marijuana use can:
- Can contribute to depression, anxiety and personality disorders.
- Compromise the ability to learn and remember information, making it more likely to fall behind the norm on developing intellectual, job and social skills.
- Affect the user's ability to remember and learn for days or even weeks after abstinence from smoking.
Effects on StudentsDaily marijuana use has been shown to:
- Cause users to get lower grades and become less likely to graduate, compared to students who do not smoke.
- Significantly impair skills related to attention, memory and learning even after not smoking for 24 hours.
- Cause problems in sustaining and shifting attention.
- Effect the ability to register, organize and use information, even compared to occasional users of marijuana.
- Impair users' ability to recall words from a list even a week after quitting marijuana use.
Effects on Work PerformanceThese are some of the findings from research of heavy marijuana users in the workplace:
- Workers who smoke marijuana are more likely to experience increased absences, tardiness, accidents, workers' compensation claims, and job turnover.
- Workers who test positive for marijuana use have 55 percent more industrial accidents, 85 percent more injuries, and a 75-percent increase in absenteeism compared to non-smokers.
- Heavy marijuana abusers self-report that their use of the drug had negative effects on their cognitive abilities, career status, social life, and physical and mental health.
The good news for heavy marijuana users is the same research shows that cognitive abilities begin to return after four weeks, even after long-term daily use of the drug.
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