It's just recently been legalized in Germany, and for very good reasons.

Compared to legal drugs like alcohol, which will cause 1 in 20 deaths just this year, cannabis is pretty mild.

So to justify harsh prosecution and punishment, its negative effects have been wildly overstated.

Naturally, there was a lot of pushback, and here something went wrong.

If you've followed the discourse over the last few years, you might have got the impression that weed has almost only upsides and few, if any, negative side effects.

We ourselves contributed to that narrative.

What made this worse is that criminalization made it very hard for scientists to study cannabis, especially its long-term effects.

They faced bureaucratic and legal hurdles, and studies often had to rely on small sample sizes.

In the last few years, this finally started to change, so it's time to bring new evidence to the discussion.

And, well, it's not pretty.

While weed is still much less harmful than alcohol, it does have a dark side.

It is more addictive than we thought, and can have significant negative effects if you use it long-term.

It seems that, uh, what are you doing?

Before you tell us how dumb we are, please watch the video.

To be crystal clear, we think prohibition doesn't work and cannabis should be legal, but this also means that we need to treat it as what it is, a drug, with unique upsides and downsides.

So let's take an honest look at some of the latest research together.

Weed is getting stronger and stronger.

Cannabis' magic juice is tetrahydrocannabinol, THC.

It docks on your cannabinoid receptors, which affects various brain functions.

THC activates some regions and calms down others, creating a fun cocktail of sensations.

The more THC, the more intense the high.

And people seem to be into higher highs, or at least this is what the market is providing.

In the US, Canada, and in Europe, the concentration of THC in legal and illegal cannabis products has more than doubled in the last few decades.

While ever more potent strains are bred, products like edibles or concentrates with more than 60% THC have become increasingly common, while the share of products with less than 15% THC has declined.

Unfortunately, just about every problem weed creates gets worse at higher THC doses.

At the same time, more and more people use weed.

In the US, more people consumed cannabis daily than alcohol for the first time in 2022.

In Canada, 26% of people 16 and older use it, up from 22% in 2018.

It's not possible to say if legalization is the reason for this, though, since studies are pretty inconsistent and vary massively between different users.

In some, consumption went up, in others it stayed stable, and the trend to use more weed began in the early 90s and sped up in the 2000s, way earlier than legalization.

So today, more people consume more weed than ever before in the last century, and it's the strongest it's ever been.

What are we seeing as a result of this?

Let's start with something that used to get you laughed out of the room, addiction.

Weed addiction and withdrawal symptoms.

A big narrative about weed is that it's not addictive, or at least not that big of a deal.

And for most people, this is true.

Studies clearly show that the majority handle it well.

For 8 out of 10 using weed, it's just a casual high and not problematic at all.

About 2 in 10 users develop a cannabis use disorder, or CUD.

CUD has 11 different symptoms, from the inability to stop when you've had enough, to using it when you know it will have negative consequences, to tolerance and withdrawal.

They can all basically be reduced to, you're doing it too often, even if it's bad for you, and it's less fun than it could be.

There are three major risk factors here.

The amount of THC, how often you consume, and your age when you start using cannabis.

The more THC, the more often, and the younger you are when you start, the higher your risk.

If you smoke too much weed too often, it will have negative impacts on your life.

So if this is you, toning it down a bit will make a big difference. 1 in 10 users develops a serious addiction.

They usually consume daily, and their life is significantly impaired or held back because they spend a lot of their time either using or recovering from cannabis use.

Since their brain is building a tolerance, they need increasingly high doses or stronger weed, often both.

Studies found a variety of negative effects.

Heavy users can experience bad moods, feel irritable, restless, paranoid, anxious, and even depressive.

In a sad twist of irony, for many addicts it feels like they need weed to fight these symptoms.

Maybe it did actually help at first, while in reality it makes those symptoms stronger and more persistent.

Studies also found that loneliness and frequent cannabis use go hand in hand.

If you feel lonely, you're more likely to use weed, and if you use weed, you may experience more loneliness.

It's not always easy to say which came first, but they seem to reinforce each other.

So on the one hand, cannabis makes loneliness feel much less bad.

On the other hand, it can also make you feel more socially awkward than you actually are, and withdraw from friends.

This can lead to a downward spiral that ends in self-isolation and chronic loneliness.

Another thing many people who consume a lot experience is a mental numbness that makes boredom feel okay because it impacts the reward system of your brain.

Not great, but good enough.

You can spend your day's killing time binging mildly interesting stuff.

Being numb rather than having fun.

Boredom is a signal to your mind to get creative or learn something new, but this is suppressed.

This also makes quitting so much harder because your daily routines suddenly seem boring and unexciting, making it very tempting to go back.

If you find yourself using constantly, this can also stunt your development as a person.

The numbness dulls bad feelings, making it easy not to deal with them.

But in life, you can only get over bad feelings if you actually feel them, and you have to process them to grow.

Lastly, let's talk about physical withdrawal symptoms.

The more you consume, the worse they'll be for you, especially if you use daily.

Withdrawal can cause headaches and sweating or chills, decreased appetite, in severe cases even fever, nausea and abdominal pain.

You might have trouble falling asleep, and if you do, you might have disturbing and vivid dreams.

The withdrawal can put you in a depressive mood where life feels daft and pointless.

You can feel restless, angry, anxious or nervous.

You may feel unable to do anything at all.

After a few days, these symptoms will begin to subside, and after a few weeks, they'll be gone entirely.

The exact time depends on how much and how long you've been consuming cannabis.

Now, let's get to the worst part.

Weed may damage your brain.

This section was not fun to research, because there's fierce debate among researchers how bad weed is for your brain, and whether it has irreversible long-term consequences or not.

There's no consensus yet, and it's hard to say anything definitive.

Having said that, THC directly interferes with critical brain chemistry.

There is some evidence that it may alter its structure.

If it does, this may go away again if you quit after a few years, or not.

We don't know yet.

The consequences vary a lot between individuals, but especially for heavy users, they have a variety of potentially unfunny downsides.

The most common one is that your memory gets significantly worse.

Sustained heavy use may reduce your ability to learn, your reasoning, perception, attention span, decision making, language abilities, and impulse control.

Most negative effects seem to go away, or at least weaken over time after you quit.

But again, we simply don't know enough and need more research.

Where the evidence is much clearer is that consuming a lot of weed is really bad for teenagers on multiple levels.

If you start using heavily early, you have many more years to build up potentially negative side effects.

Teens who use a lot are much more likely to become addicted to weed.

This may just be correlation and weed may not be the underlying cause, but heavy weed users are more likely to perform poorly in school and less likely to finish their education.

They are on average less satisfied with their life and what they've achieved.

This may simply be because if your memory and motivation are stunted, you have fewer interesting experiences and forget the ones you do have.

And there is strong evidence that teen users are way more likely to develop mental health issues like psychosis, schizophrenia, depression, or anxiety later in life.

Once again, the younger you start, the higher the risk.

And it also seems to rise massively with high THC doses, making highly potent cannabis products even more dangerous for teens.

Okay, let's wrap this up.

We've only focused on the negative sides in this video.

That was the whole point.

As we said before, for most people, weed in moderation is totally fine and definitely way less harmful than alcohol.

You do you, we're not your parents.

The upside of moderation is also that when you do it, your experience will be more intense and special.

But for teens, weed, especially using it regularly or a lot of it, is a bad idea with potentially life-changing consequences.

We know that criminalization did nothing to make this better.

We now have a new chance under legalization.

It begins with being open and honest about the state of science and acknowledging that weed is one drug among many others.

Certainly not the worst one by a long shot, but also problematic for at least 1 to 3 out of 10 people using it.

If you really have to try cannabis, there is a time and place, and that's in your 20s.

If you're younger, the science is clear, don't do it.

At least, not yet.

You'll have plenty of time to experiment later.

Let's do a different experiment now.

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