Weed Warnings

Ask the DOC

The enthusiasm by advocates of the legalization of marijuana is diverting attention from the drug’s many adverse health effects. Multiple clinical studies have demonstrated that chronic marijuana use is associated with long-term damaging effects on cognition. Many studies have additionally shown that when compared to non-users, regular use of marijuana diminishes the brain’s executive functions, attention, learning, memory, and motor skills. In addition, these altered brain functions may persist long after cessation of marijuana use. Even more concerning is emerging data suggesting that when marijuana use begins prior to completion of brain maturation (which usually occurs at about age 21), changes in brain function and structure may occur and persist. As one can imagine, these findings may have major medical and social implications.

Marijuana use starts early in many Americans and is the most commonly used illicit drug in Americans 12 years of age and older. In 2019, seven percent of eighth graders, 15 percent of tenth graders, and 21 percent of twelfth graders have reported use of the drug, and these numbers are most likely underestimated. Lifetime marijuana use in 2016 averaged 15 percent for ages 12-17, 52 percent for ages 18-25, 46 percent for ages 26-65, and 22 percent for age 65 and older. Few Americans believe that cannabis, or marijuana, is harmful to one’s health, and legalization of its use has increased the public’s interest in its possible benefits. However, regular use of marijuana is associated with a range of behavioral abnormalities. Adolescents who use it are much more likely to become addicted than those who start at a later age. Regular use is associated with declines in short-term memory and cognitive function leading to poor school or work performance, mood disorders, and psychosis. In addition, it impairs the ability to operate machinery like motor vehicles and this effect, like alcohol, is dose-dependent. Car accidents occur two to seven times more frequently while using marijuana, a fact often cited by those who oppose legalization.

Recent studies have shown that there is evidence of permanent neurological changes associated with marijuana use that begins prior to age 21. Evidence of neuropsychological dysfunction has been seen with its use, and these changes were permanent in those who started using the drug prior to age 21, even if they stopped using it. The probable explanation for these permanent deleterious effects can be found in the biology of brain development. Studies using diagnostic brain imaging has shown abnormal brain anatomy in those who began use before age 21. These studies have used standard street cannabis, which contains about 10 percent THC (tetrahydrocannabinol). Marijuana has over 120 psychoactive compounds termed cannabinoids, including THC. Some synthetic cannabis products contain much higher amounts of THC, for example concentrated cannabis extracts which may contain up to 80 percent. Imagine how magnified the ill effects of the drug would be if the person used a compound eight times stronger than street marijuana.

As our liberal elected representatives seem hell bent on legalization, they would be wise not to legalize its sale to those under age 21, lest they create a generation of poorly functioning and dysfunctional individuals.

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