It’s the most common date rape drug, hospitalizes more people than heart attacks, causes cancer and, in large enough doses, can end in coma and death.
If alcohol were discovered today, it would probably be outlawed, says David Nutt.
The former chief drugs adviser to the British government was fired in 2009 for saying alcohol is more dangerous than LSD, ecstasy and cannabis and that his Labour government bosses were wrong to want to toughen laws around marijuana.
“We minimize the effects of alcohol,” said Nutt, a professor of neuropsychopharmacology at Imperial College London. Cannabis, by contrast, “is an exceptionally safe drug.”
Those who study the effects of drugs generally agree that alcohol is statistically more harmful than pot — for one thing, its hard to overdose and die from cannabis. But the pot vs. booze story is nuanced. Cannabis has been under prohibition for so long (nearly 100 years in Canada) that not enough research has been done on its good and bad effects, and studies from the 70s and 80s used pot that was far less potent than what’s available today.
Another wildcard is what will happen under legalization. When marijuana becomes as freely available as beer and wine, and Canadians can have weed shipped to their door, will harms rise?
Here’s a breakdown of what research says about alcohol and marijuana.
First, some biology:
When we drink, alcohol goes into the stomach, where some of it gets broken down immediately and the rest, about 80 per cent, gets absorbed into the bloodstream and ferried to the liver and up to the brain. There, it interferes with the communication between nerve chemicals. Among other things, alcohol affects brain regions involved in controlling behaviour, emotions and decision-making.
With the first drink, people start experiencing a kind of mild euphoria. They become more talkative, more self-confident, more socially uninhibited. As the level of alcohol increases, it affects the frontal lobe, making it harder for people to control their emotions.
Later, as blood alcohol concentrations level off and start to fall, the effects become more sedating, affecting coordination, speech and mood. Booze also affects the hippocampus, the part of the brain where memories are laid down, which may explain why people can black out from too much drinking.
When you smoke pot, THC (the principle active component of weed) quickly diffuses to the brain, flooding receptors that ordinarily react to natural THC-like chemicals. Blood levels reach a maximum after about 30 minutes, then quickly subside within one to three hours.
Cannabis dampens down neurons involved in motor response and excitation, and time seems to slow down. Rather than euphoria, people tend to experience pleasure, calm, and an altered sense of perception and perceived creativity, said Dr. Peter Selby, director of medical education at the Centre for Addiction and Mental Health. “There isn’t this disinhibition that you will often see with alcohol,” Selby said. With pot, for the most part, “you get people sort of chilling out.” Weed can cause paranoia in people who aren’t tolerant to it, or who are vulnerable to psychosis. “But that’s not the usual effect,” Selby said.
The risk of getting hooked
Surveys show the vast majority (80 per cent) of Canadians drink and many are drinking more than they should (19 per cent, roughly 5.8 million people, reported booze consumption in 2016 that classified them as heavy drinkers). A lot (40 per cent) of drinking happens between Monday and Friday.
According to Statistics Canada, only 14 per cent of Canadians (roughly 4.2 million people) reported using cannabis in the past three months, with 56 per cent of them daily or weekly users. It’s not clear how many people who aren’t currently using pot will pick up the habit when it becomes legal. Estimates range from about half a million to three million.
“Clearly the expectation is that usage is going to increase,” Michael DeVillaer of McMaster University said at a recent conference on legalization hosted at McGill University. For one thing, pot retailers will be local, legal and visible. “You won’t have to worry about being in your favourite dispensary when the police come crashing in.”
Researchers at the National Institute on Drug Abuse in the U.S. reported in 1994 that about 15 per cent of people who have ever tried alcohol eventually fit a diagnosis of dependence, versus nine per cent of pot users. The younger people start using cannabis, and the greater their use, the higher the likelihood of developing a problem.
Effects on the body and brain
Alcohol has been associated with cancers of the larynx, esophagus, breast, colon and liver. The greatest risks come with heavy, long-term use, the American Society of Clinical Oncology reported in January. In 2016, about 77,000 Canadians were hospitalized as a direct result of alcohol, compared to about 75,000 for heart attacks, according to the Canadian Institute for Health Information. Alcohol is also blamed for more than 4,000 premature deaths each year.
In February, a study published in The Lancet Public Health Journal based on more than one million adults diagnosed with dementia in France concluded chronic, heavy drinking is a major preventable risk factor for the brain disease. The same month, a study by American researchers who examined the brain scans of more than 1,000 people found long-term alcohol use was associated with a decrease in grey and white matter volume in adults, and lower grey matter volume in adolescents.
Pot use isn’t associated with changes in brain structure. The University of Colorado Boulder team didn’t see anything that reached statistical significance. The caveat, of course, is that the absence of evidence doesn’t necessarily mean something doesn’t exist, said co-author Kent Hutchison, a professor of behavioural neuroscience. “But clearly (alcohol) seems to have a more profound effect than cannabis,” he said.
Still, weed isn’t benign. One study of more than 1,000 New Zealanders who started using cannabis in their teens, and kept using it for years, showed an average decline in IQ of eight points between age 13 and 38. People who started using marijuana after adolescence, however, didn’t show notable drops in IQ.
Smoking cannabis alone doesn’t appear to increase the risk for cancers of the lung, head or neck, although there’s modest evidence linking it to one type of testicular cancer.
Cannabis is used daily by millions worldwide, but there has never been a reported case of anyone overdosing on weed alone. In 1988, a U.S. Drug Enforcement Administration judge wrote that a pot smoker “would theoretically have to consume nearly 1,500 pounds of marijuana within about fifteen minutes to induce a lethal response.”
In the U.S., an average of six people die of alcohol poisoning each day.
The effect on sex
In a recent study, New York University researchers asked 679 nightclub and dance festival attendees aged 18 to 25 about their thoughts on the sexual effects of alcohol, pot and ecstasy. Alcohol and ecstasy were more strongly associated with feeling more attractive, sexual desire, length of intercourse and “sexual outgoingness.” But booze and ecstasy were also more likely to increase sexual dysfunction in men (pot more so for women). “Post-sex regret” was also most common after alcohol (31 per cent) compared to marijuana (seven per cent).
More alarmingly, studies suggest alcohol is the most commonly used drug in date rape. “The media really love to rack up fears about new drugs,” Nutt said, “In reality, almost all cases of date rape are due to people getting girls very drunk.”
The dark side of booze
Alcohol has been implicated in about half of all violent crimes. It’s not clear why, but recently, researchers gave 50 young men either vodka shots or a placebo and slid them inside an MRI scanner. When they performed a task designed to get them seriously wound up, the intoxicated men showed decreased firing in the prefrontal cortex, the region that co-ordinates emotional control, among other functions.
“We think normally people restrain their aggression through conscious and subconscious processes, and alcohol dissolves that, so they explode,” Nutt said.
However, a 2002 Canadian Senate report concluded that marijuana itself isn’t a cause of violence, delinquency or crime. Overall, the committee found that “for the vast majority of recreational users, cannabis use presents no harmful consequences for physical, psychological or social wellbeing in either the short or the long term.”
Selby, of the centre for addiction, said the problem with booze is that social constraints aren’t sufficient to creat “normative” drinking patterns. Instead, it’s a kind of free for all. “We get bombarded with a lot of advertising, the culture is about drinking to intoxication,” particularly in university, he said.
Nutt said we could see a slight bump in social harms with pot legalization, although he doubts masses of people will suddenly start sparking up spliffs.
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