Marijuana: Age at First Use Has Impact
A new report from SAMHSA's Office of Applied Studies
(OAS), Age at First Use of Marijuana and Past Year
Serious Mental Illness, found that among persons
age 18 or older, those who first used marijuana before
age 12 were twice as likely to have serious mental illness
in the past year as those who first used marijuana at
age 18 or older.
"Kids today are using marijuana at younger ages,
putting them at greater risk for future health and mental
health problems," said Mr. Curie. "We have
found that younger persons who start smoking marijuana
are at greater risk of developing an addiction and serious
mental illness later in life."
Marijuana is the most widely used illicit drug, and
it is usually the first drug used by persons who use
The report, from SAMHSA's National Survey on Drug Use
and Health (NSDUH), cites recent research pointing to
an association between early marijuana use and a heightened
risk of developing schizophrenia or other psychological
Data from NSDUH show that among persons age 18 or older
who reported lifetime marijuana use, 55 percent reported
first using marijuana before age 18.
In addition, males age 18 or older were more than twice
as likely as females to report that they first used marijuana
before age 12.
In 2002 and 2003, 42.9 percent of persons age 18 or
older (an estimated 90.8 million persons) had used marijuana
at least once in their lifetime. Among adults age 18
or older, lifetime marijuana use varied by gender48.4
percent of males reported lifetime use, while 37.9 percent
of females reported lifetime use.
All of the findings presented in this report are annual
averages based on the combined data from the 2002 and
NSDUH asked persons age 12 or older to report on their
use of marijuana, including their age at first use. For
persons age 18 or older, NSDUH also asked questions to
assess serious mental illness during the 12 months prior
to the survey.
For a copy of the OAS report, Age at First Use of
Marijuana and Past Year Serious Mental Illness,
contact SAMHSA's National Clearinghouse for Alcohol and
Drug Information at P.O. Box 2345, Rockville, MD 20847-2345.
Telephone: 1 (800) 729-6686 (English and Spanish) or
1 (800) 487-4889 (TDD). Online, the report is available
on the SAMHSA Web site at www.oas.samhsa.gov/2k5/MJageSMI/
Back to Top
Back to Graphic Version