Cannabis is one of the most powerful healing plants on the planet. Dozens of studies have made pseudoscientific attempts to indicate that young people who use cannabis tend to experience psychological, social problems and mental decline. However, there is no evidence that marijuana use is directly linked with such problems, according to the results of a study published in The Lancet.
Marijuana was *mostly* legal until 1970 when it became classified as a hard drug. No one thought of it as a dangerous or illicit drug until the 20th century.
"Currently, there is no strong evidence that use of cannabis of itself causes psychological or social problems," such as mental illness or school failure, lead study author Dr. John Macleod of the University of Birmingham in the UK told Reuters Health.
"There is a great deal of evidence that cannabis use is associated with these things, but this association could have several explanations," he said, citing factors such as adversity in early life, which may itself be associated with cannabis use and psychosocial problems.
Macleod and his team reviewed 48 long-term studies, 16 of which provided the highest quality information about the association between illicit drug use reported by people 25 years old or younger and later psychological or social problems. Most of the drug-specific results involved cannabis use.
Cannabis use was not consistently associated with violent or antisocial behavior, or with psychological problems.
In another study, Scientists from King's College, London, found occasional pot use could actually improve concentration levels.
The study, carried in the American Journal of Epidemiology, tested the mental function and memory of nearly 9,000 Britons at age 50 and found that those who had used illegal drugs as recently as in their 40s did just as well, or slightly better, on the tests than peers who had never used drugs.
'Overall, at the population level, the results seem to suggest that past or even current illicit drug use is not necessarily associated with impaired cognitive functioning in early middle age,' said lead researcher Dr Alex Dregan.
Dr Dregan's team used data on 8,992 42-year-olds participating in a UK national health study, who were asked if they had ever used any of 12 illegal drugs. Then, at the age of 50, they took standard tests of memory, attention and other cognitive abilities.
Overall, the study found, there was no evidence that current or past drug users had poorer mental performance. In fact, when current and past users were lumped together, their test scores tended to be higher.
But that advantage was small, the researchers said, and might just reflect another finding - that people who'd ever used drugs generally had a higher education level than non-users.
'In a Western population of occasional drug users, this is what you'd expect to see,' said John Halpern, a psychiatrist at Harvard Medical School.
'In some ways, this is not surprising. The brain is resilient.'
Though some studies have found that drugs like cannabis and cocaine may cloud thinking, memory and attention in the short term, the current findings support the notion that those effects may be temporary, Dr Dregan's team said.
Othher investigators at the University of California at San Diego examined white matter integrity in adolescents with histories of binge drinking and marijuana use. They reported that binge drinkers (defined as boys who consumed five or more drinks in one sitting, or girls who consumed four or more drinks at one time) showed signs of white matter damage in eight regions of the brain.
By contrast, the binge drinkers who also used marijuana experienced less damage in 7 out of the 8 brain regions.
"Binge drinkers who also use marijuana did not show as consistent a divergence from non-users as did the binge drink-only group," authors concluded. "[It is] possible that marijuana may have some neuroprotective properties in mitigating alcohol-related oxidative stress or excitotoxic cell death."
Alarmist claims that experimenting with cannabis will inevitably lead to the use of other illicit drugs persist in the media despite statistical data indicating that the overwhelming majority of those who try pot never go on to use cocaine or heroin.
Moreover, recent research is emerging that indicates that pot may also suppress one's desire to use so-called hard drugs.
In June, Paris researchers writing in the journal Neuropsychopharmacology concluded that the administration of oral THC in animals suppressed sensitivity to opiate dependence.
One of the most important roles cannabinoids play is in the suppression of cancer. The research in this area is being increased every year as many more groups of scientists are discovering the powerful healing properties of cannabis.
Health benefits of marijuana are now well documented. From depression and anxiety relief to reduced blood pressure, pain alleviation and glaucoma treatment. It is not addictive, does not kill brain cells and is not a “gateway” drug -- in fact, when pot is more available, studies show that the use of hard drugs like heroin and cocaine actually decreases.
It's time governments around the world release their restrictions on this plant to all populations so that they may freely use one of mother nature's most healing plants.
Marco Torres is a research specialist, writer and consumer advocate for healthy lifestyles. He holds degrees in Public Health and Environmental Science and is a professional speaker on topics such as disease prevention, environmental toxins and health policy.