Seriously? I thought this was pretty commonly accepted, even among pro-drug people. Anyway,
a recent study indicates that it does indeed induce paranoia, and it's not "incredibly rare", either:
So, there's a bit more to it than "60s anti-drug fantasies". AFAIK, no studies have linked
aggression to cannabis, though. It seems to be the polar opposite to alcohol, at least in that regard.
[sidetrack]You've cited such a bad study I have to address it briefly even though it is a sidetrack in this thread.
Here is one claim in that news report (not the study itself, BTW):
For instance, our study of the population of England found that the belief that people are deliberately trying to harm you is three times as common among cannabis users as it is among non-users.
They admit there was no cause and effect established. But the finding itself was rather incredible so I looked up the source.
Here's the study they cite in their introduction:
Concomitants of paranoia in the general population.
RESULTS:
The prevalence of paranoid thinking in the previous year ranged from 18.6% reporting that people were against them, to 1.8% reporting potential plots to cause them serious harm. At all levels, paranoia was associated with youth, lower intellectual functioning, being single, poverty, poor physical health, poor social functioning, less perceived social support, stress at work, less social cohesion, less calmness, less happiness, suicidal ideation, a great range of other psychiatric symptoms (including anxiety, worry, phobias, post-traumatic stress and insomnia), cannabis use, problem drinking and increased use of treatment and services.
If 18% of the population believe someone is against them, how do you know that is paranoia as opposed to a fact someone is actually against those 18%? I would suggest it's even higher than that. A lot of people actually are against other people.
And nowhere in that abstract does it say the study found this claimed finding:
For instance, our study of the population of England found that the belief that people are deliberately trying to harm you is three times as common among cannabis users as it is among non-users. The belief that people are trying to cause you serious injury or harm is five times as common among cannabis users.
So are they lying? Did they run their own study on the data? Why is such an important finding not in the abstract of the study they are citing as uncovering that finding?
As for the "largest study to date":
We recruited 121 volunteers, all of whom had taken cannabis at least once before, and all of whom reported having experienced paranoid thoughts in the previous month (which is typical of half the population).
121 subjects is barely more than a pilot study.
And they started with people who already reported paranoia. They claim that's a random sample because half the population reports such paranoia? Since when is 18% half the population? And it wasn't even established that was paranoia as opposed to a simple fact?
More importantly, they did not establish that their 121 subjects were the same as the claimed 50% of the population. It's a long way from an increase in paranoia in a random population sample. Instead they specifically selected the test subjects.
They injected THC. Gawd knows what different effect that resulted in.
Half of those given THC experienced paranoia, compared with 30% of the placebo group: that is, one in five had an increase in paranoia that was directly attributable to the THC.
OMG. Talk about bad research red flags, that summary is full of them.
But forget the news report, we've already seen they misrepresented the study in their study's introduction. Let's look at the actual study:
How Cannabis Causes Paranoia: Using the Intravenous Administration of ∆9-Tetrahydrocannabinol (THC) to Identify Key Cognitive Mechanisms Leading to Paranoia
Paranoia is associated with use of the most commonly taken illicit drug, cannabis.
Say what? That's a claim they started with, before they even did the study.
A total of 121 individuals with paranoid ideation were randomized
OK, stop right there. They are testing to see if IV THC increases paranoia in patients with established paranoia.
How does that apply to everyone else? In the news summary they claimed half the population met this criteria. Sure doesn't sound like it.
In this largest study of intravenous THC, it was definitively demonstrated that the drug triggers paranoid thoughts in vulnerable individuals.
Gee, I guess paranoid schizophrenics shouldn't smoke pot.
Of course they claim they excluded people with mental illness diagnosis so what did they mean by already paranoid subjects:
There were 121 participants. The inclusion criteria were: aged between 21 and 50, had taken cannabis at least once before, and reported a paranoid thought in the past month as assessed by the Paranoid Thoughts Scale Part B.21 ...
Screening criteria:
did not report persecutory ideation (n = 739), had a history of mental illness (n = 281),
So they asked people if they wanted to be in a pot study and excluded people who self reported mental illness. Would you admit you had a mental illness if you wanted to be in the study?
They then only included people who reported persecutory ideation. You can read how they determined that. Were they going for people who had paranoid ideation but either were not yet diagnosed, weren't sick enough to be called ill, or were mentally ill as long as they denied it to the researchers?
That's only the more minor problems.
Here's the major one. They had three groups, one got placebo, one got the THC, and one got the THC plus educational material on the effects of THC.
The cognitive awareness condition, given before THC administration, involved a simple 5-minute educational module, explaining the range of effects that the drug can cause (THC was considered synonymous with cannabis for this procedure).
Now look at
the results.
The group that actually showed increased paranoia was the group they told might experience paranoia.
This study has so many problems.
I'm sorry but millions of people use marijuana on a regular basis. I can assure you these studies that purport to find all these problems are usually baloney.
If you are getting your ideas about marijuana from these news accounts you need to keep one thing in mind. There are some of the most blatantly anti-marijuana biased studies on this subject. It's on the same level as studies from the 50s that found mothers made their kids autistic. [/sidetrack]