35 answers · from the studies · short videos
You’ve been high your whole life.
Cannabis works by borrowing a system your body already runs. Short videos on what THC, CBD and your own cannabinoids actually do, each answered from the research. I'm Justin Hartfield and I welcome you to a little slice of my brain (on weed).
7:25 Start here
Endocannabinoid System Explained: The Cannabinoids You Make
The endocannabinoid system is your own locks and keys: CB1 and CB2 receptors and the cannabinoids you make, anandamide and 2-AG. THC borrows it.
Every answer
The questions people actually ask
35 answers · 304 chapters
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4:14 What THC does What does THC do to your brain?
It's the molecule in cannabis that gets you high, and in your brain it holds a built-in brake, the CB1 lock, on everywhere at once.
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6:56 What THC does What happens when you smoke weed?
THC reaches your brain in seconds and turns on CB1 locks everywhere: your heart speeds up, eyes redden, mouth dries.
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7:08 What THC does How long do edibles last?
Edibles usually last 6 to 8 hours, sometimes up to 12, and take 30 to 90 minutes to kick in. Why they hit harder: your liver makes 11-hydroxy-THC.
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8:24 What THC does How long does THC stay in your system?
After one joint, a urine test usually stops finding THC within one to four days. Someone who smokes every day can stay positive for weeks.
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1:12 What THC does Can you get a contact high?
A contact high showed up only in heavy smoke in a sealed room, small and short; with home-like airflow, non-smokers reported no drug effect.
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4:08 What THC does CBD vs THC: what's the difference?
CBD vs THC: same plant, same atoms. THC turns the CB1 lock in your brain and gets you high; CBD barely touches it, so it doesn't. Here's why.
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4:00 What THC does Is weed a depressant?
Not exactly, and not a stimulant either: THC works on a brain brake that sits on calming and exciting cells, so dose decides.
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5:58 The plant & its compounds Indica vs sativa: what's the difference?
Indica and sativa labels promise a body high or a head high, but DNA and lab tests show the names match a plant's genes and chemistry only loosely.
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5:44 The plant & its compounds THCA vs THC: what's the difference?
THCA is the form the cannabis plant actually makes. It barely fits the CB1 lock that THC turns, so on its own it doesn't get you high.
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6:26 The plant & its compounds What does CBD actually do?
CBD clearly cuts seizures in two rare childhood epilepsies. For anxiety and sleep, the trials are small and the results mixed.
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4:45 The plant & its compounds What are CBN, CBG and CBC?
CBN, CBG and CBC are lesser-known cannabinoids: CBGA is a plant precursor, CBC shares that pathway, and CBN forms as THC ages.
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6:27 The plant & its compounds What are terpenes in weed?
Terpenes are the molecules you smell in cannabis. Only two controlled trials have added one terpene to THC: in one it helped, in the other it didn't.
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6:42 The plant & its compounds What is delta-8, and what is HHC?
Delta-8 and HHC are close copies of THC, mostly made in a lab from hemp CBD, and both turn the same CB1 lock that THC holds open.
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4:02 Too much What is greening out?
Greening out is taking more THC than your body can handle: a racing heart, dizziness and panic. It passes. Here's why it happens and how to come down.
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4:04 Too much Can you overdose on weed?
You can take far too much THC, but nobody has found a dose that stops a healthy adult's breathing, because THC barely touches your brainstem.
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6:06 Too much What is CHS?
Cannabinoid hyperemesis syndrome (CHS) is repeated attacks of severe vomiting after long, heavy cannabis use. It goes away when people stop.
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8:17 Too much Is weed addictive?
Weed is addictive for some: an estimated 1 in 11 who use it become dependent, and about half of regular or dependent users go through withdrawal.
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4:27 Too much Why does weed make you paranoid?
THC works on your brain's fear system, and dose decides: a little can calm you, a bit more can scare you.
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5:43 Too much Can weed cause psychosis?
Cannabis can cause psychosis, though the risk is small in populations of people with no prior signs of mental illness.
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4:08 Too much Does weed kill brain cells?
There's no good evidence that weed kills brain cells in people. Where the idea came from, what THC changes and how it comes back, and what twins show.
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9:49 Too much Does smoking weed cause lung cancer?
The big studies haven't shown that smoking weed causes lung cancer, but they haven't ruled it out for heavy, long-term smokers either.
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4:07 Hunger Why does weed make you hungry?
THC switches on CB1, the lock your body uses to run hunger. In mice, that lock sharpens smell and flips fullness cells.
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10:37 Hunger Does weed make you lose weight?
Not directly: THC makes you eat more, yet people who use it are less often obese. Here's what the science shows.
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4:01 Hunger Why am I always hungry?
Partly your endocannabinoid system: it makes its own cannabinoids from fats like linoleic acid, the omega-6 in seed oils.
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7:25 Your own system What is the endocannabinoid system?
The endocannabinoid system is your own locks and keys: CB1 and CB2 receptors and the cannabinoids you make, anandamide and 2-AG. THC borrows it.
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4:04 Your own system Is runner's high real?
The runner's high is real, and the best explanation is endocannabinoids, cannabinoids your body makes, more than endorphins. Here's how to get one.
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4:01 Your own system How do you get a natural high?
A natural high is your own chemistry: cannabinoids your body makes, plus dopamine. Here's how to get high without weed, from a long run to cold water.
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4:11 Your own system Can your brain make its own painkiller?
The placebo effect is real relief from expecting a treatment to work. Your brain answers with its own painkillers: opioids and cannabinoids.
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4:00 Mind & memory How do you let go of the past?
How to let go of the past: in your brain, letting go means learning a newer lesson that wins out over the old one. Here's the mouse that shows it.
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4:09 Mind & memory Can your brain unlearn a fear?
Fear extinction is how your brain unlearns a fear: it learns a newer lesson, that this is safe now. In mice, that needs the CB1 lock at that moment.
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4:20 Life itself How does the body heal itself?
Inflammation is how your body heals itself: a fight that clears the damage, then a cleanup that switches it off. How both work, stage by stage.
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7:44 Life itself Why do we age?
Damage builds up faster than the body clears it, and the inflammation that heals you stops switching off. That is inflammaging.
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5:59 Life itself What is Bryan Johnson's Don't Die?
Don't Die is Bryan Johnson's rule: measure everything in your body and do whatever it takes not to die. I think it misunderstands what life is.
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8:33 Life itself What is life?
Physics gives a good answer: chemistry that stays organized by running energy through it, and copies itself. Are viruses alive? Is fire?
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5:34 Life itself Is time travel possible?
Forward time travel is real but tiny: atomic clocks have measured it. Backward, nobody has found a way, and the arrow of time says you can't go back.
7 free games
Science you can play.
Put THC in the CB1 lock. Brake a synapse before it overheats. Find the hidden platform in the pool. Free browser games on the endocannabinoid system and what cannabis does in your brain, built on the same studies as every answer here, in English, Spanish and German.
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