WASHINGTON, D.C. — The Marijuana Policy Project is challenging U.S. Drug Czar Gil Kerlikowske to explain the self-contradicting statement he included in an invitation to the first-ever White House Drug Policy Reform Conference, which will be held Monday from 9 a.m.–2 p.m. It can be viewed online at http://www.whitehouse.gov/live

The email invitation distributed Friday by the Office of National Drug Control Policy included a graphic with the following quote from Kerlikowske: “Drug policy reform should be rooted in NEUROSCIENCE—NOT POLITICAL SCIENCE.”

“Every objective study on marijuana has concluded that it poses far less harm to the brain than alcohol,” said Mason Tvert, director of communications for the Marijuana Policy Project and coauthor of the book Marijuana Is Safer: So why are we driving people to drink? “The ONDCP has long championed laws that steer adults toward using alcohol and away from making the safer choice to use marijuana. If the drug czar is truly committed to prioritizing neuroscience over political science, he should support efforts to make marijuana a legal alternative to alcohol for adults.”

According to the National Institute on Alcohol Abuse and Alcoholism, “[H]eavy drinking may have extensive and far–reaching effects on the brain, ranging from simple ‘slips’ in memory to permanent and debilitating conditions that require lifetime custodial care.” It specifically notes that those who drink heavily over a long period of time “may have brain deficits that persist well after he or she achieves sobriety.” http://pubs.niaaa.nih.gov/publications/aa63/aa63.htm

Meanwhile, there is significant evidence demonstrating that even frequent long-term marijuana use does not pose significant or permanent damage to the brain.

A 2009 study by researchers at San Diego State University and the University of California, San Diego specifically concluded that marijuana does not pose as much harm as alcohol. In the journal Clinical EEG and Neuroscience, they reported:

“Abnormalities have been seen in brain structure volume, white matter quality, and activation to cognitive tasks, even in youth with as little as 1–2 years of heavy drinking and consumption levels of 20 drinks per month, especially if >4–5 drinks are consumed on a single occasion. Heavy marijuana users show some subtle anomalies too, but generally not the same degree of divergence from demographically similar non-using adolescents.” http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2827693/

Researchers at Harvard University reported in the American Journal on Addictions in 2005:

“When compared to control subjects, [marijuana] smokers displayed no significant adjusted differences in volumes of gray matter, white matter, cerebrospinal fluid, or left and right hippocampus. … These findings are consistent with recent literature suggesting that cannabis use is not associated with structural changes within the brain as a whole or the hippocampus in particular.” http://www.ncbi.nlm.nih.gov/pubmed/15804878

A 2004 study published in the journal Psychological Medicine reported “an absence of marked long-term residual effects of marijuana use on cognitive abilities.” In a 2012 article in the journal Clinical and Experimental Psychopharmacology, researchers at the University of Central Florida reported that chronic use may be associated with “small but significant” effects on neurocognitive skills for limited periods of time following use, but there is “no evidence of lasting effects on cognitive performance” after users abstained for at least 25 days.

A growing number of studies indicate that marijuana actually has neuroprotective properties, meaning it protects brain cells from harm. For example, a study published in the journal Neurotoxicology and Teratology in 2009 found that binge drinkers who used marijuana suffered significantly less damage to the white matter in their brains. http://www.sciencedirect.com/science/article/pii/S0892036209001457

Researchers have also concluded that alcohol poses more risk of addiction than marijuana. According to a 1999 report by the National Academy of Sciences Institute of Medicine, “[A]lthough [some] marijuana users develop dependence, they appear to be less likely to do so than users of other drugs (including alcohol and nicotine), and marijuana dependence appears to be less severe than dependence on other drugs.” http://www.nap.edu/openbook.php?record_id=6376

“Nobody is suggesting it is okay for teens to use any intoxicating substance,” Tvert said. “We are simply asking why adults who are of legal age to use alcohol should be punished for using a less harmful product.

“If we’re going to talk about teens, we should be discussing alternatives to the current system of prohibition, which has utterly failed to prevent teen use,” Tvert said. “There is a growing sentiment that regulating and actually controlling marijuana would be a more effective approach.”