Sunday, May 17, 2026 · 9:41 AM
ok dumb question — i've been taking creatine for the gym for like a year. just read an article saying it can also help with thinking?? is that real or supplement bro nonsense
Not dumb at all. The short answer: yes, real — but the dose you're taking is almost certainly not doing anything for your brain.
5g a day fills up your muscles. Your brain is a totally different building with a much harder front door.
Think of your muscles like a Costco — wide-open loading docks, anyone with a card walks right in. Creatine floods in easily.
Your brain is more like a federal building. There's a checkpoint (the blood-brain barrier), and only certain visitors get through certain doors.
Creatine has to use a very specific door — a transporter protein called SLC6A8. And the brain has way fewer of those doors than your muscles do.
ok but if creatine gets through *some* doors, why doesn't taking more eventually do it?
Great question. It actually does — but barely. At 5g/day you maybe nudge brain creatine up 2-3%. At 20g/day for two months you can get to ~11%.
Compare that to your muscles, which jump 20-40%. The ceiling on the brain side is just way lower.
wait so the supplement industry is basically lying when they say 5g helps cognition
Strong word, but yeah — and the EU regulator (EFSA) literally rejected that claim in 2024.
An applicant tried to get "3g/day creatine improves cognitive function" approved. EFSA reviewed 21 studies and said: nope, the evidence only holds at high doses under stress. Claim denied.
😮damn ok. so what does it ACTUALLY do for the brain then
Here's the analogy that makes it click:
Your brain runs on ATP — molecular fuel. Most of the time, the brain has a steady supply, like your phone plugged into the wall.
Creatine is a backup battery. It doesn't add power when you're plugged in — but if the wall power flickers, the backup kicks in instantly.
ohhhh so it only matters when something is going wrong??
Exactly. That's the whole punchline of the field.
If you're a healthy 25-year-old who slept 8 hours and ate breakfast — extra creatine in your brain just sits there. You won't feel sharper.
But when your brain's "wall power" gets cut? That's when the backup battery suddenly matters a lot.
what counts as wall power getting cut
Four big ones:
1. Sleep deprivation — pulling an all-nighter
2. Low oxygen — altitude, sleep apnea, breath-holding
3. Aging — your brain's own creatine factory slows down
4. Disease or injury — Alzheimer's, concussion, TBI
the all-nighter one is wild to me. like you can take creatine and not feel sleep-deprived??
Not "not feel" — more like "your brain still works while you feel tired."
There was a study where people stayed awake 21 hours straight. Half got a giant dose of creatine (~25g at once). Half got placebo.
Within hours the creatine group had restored ATP, normal brain pH, better working memory, faster processing. The placebo group kept declining.
25g AT ONCE. isn't that like a kidney bomb
😅It'll make you run to the bathroom — osmotic diarrhea is the real risk above 10g in one sitting.
But kidneys? No. That myth refuses to die.
Here's why people think it's bad: doctors test kidney function by measuring creatinine in your blood. Creatine naturally breaks down into creatinine.
oh so if you take more creatine
Yep — more creatinine in your blood. Lab result looks alarming. But it's not because your kidneys are damaged — it's because there's just more raw material breaking down.
Analogy: more cars on a highway means more exhaust. Doesn't mean any engine is broken.
Studies running people on 30g/day for FIVE years show zero kidney damage in healthy adults.
🤯ok back to the brain stuff. you mentioned alzheimer's??
This is the most exciting part honestly.
Alzheimer's is partly an energy crisis disease — the neurons are slowly running out of ATP. They're like phones at 5% battery all day.
A trial called CABA gave Alzheimer's patients 20g/day of creatine for 8 weeks. The results were genuinely surprising.
Brain creatine up 11%. Cellular ATP production almost tripled. Working memory scores up 8 points. Executive function up 5. Fluid cognition up 4.4.
In 8 weeks. With a cheap, off-patent supplement.
For context: Alzheimer's drugs that cost billions to develop usually fail to hit their target at all. This pilot trial hit the target hard.
wait so should my grandma be taking creatine
Talk to her doctor first — but this is exactly the conversation that's now happening in geriatrics and neurology circles.
The pilot was small. Larger trials are running. But the signal is strong enough that it's silly to ignore.
why was there so much skepticism about creatine and brains before then
Two reasons. First — the dose problem we talked about. Most studies used 5g and saw nothing.
Second — some big meta-analyses claimed creatine helped memory in healthy young adults. Turned out they had a math error.
Imagine you ask 10 people their favorite color. Then you ask the same 10 people their favorite shade of blue, their favorite shade of red, etc.
You'd be insane to report "I surveyed 70 people!"
That's basically what those meta-analyses did. They counted 7 memory subtests from the same participants as 7 independent results. Inflated the sample size and made the effect look real.
lmaooo
so when someone redid the math correctly?
The "creatine helps healthy young brains" effect vanished. Only older adults kept showing real benefit.
Which lines up perfectly with the backup battery story — older brains have weaker wall power, so the backup matters.
ok so to summarize: if i'm 28 healthy and well-slept, 5g for muscles is fine and probably doesn't help my brain
if i pull all-nighters or get older or get sick, high-dose could matter
❤️Nailed it. You've got the model now.
One more nuance — there's a precursor called GAA (guanidinoacetate) that gets through the brain's front door using different transporters than creatine.
So combining creatine + GAA is like having a VIP pass AND a service entrance — best results come from using both.
why not just take GAA then
Tradeoff. When GAA gets converted to creatine in the brain, the chemistry produces homocysteine as a byproduct — and high homocysteine is bad for your heart.
So pure GAA has a cardiovascular asterisk. Creatine + a small amount of GAA seems to be the sweet spot in current research.
ok last question. if i wanted to actually use creatine for brain stuff, like before a hard week of work or whatever, what would i do
Two protocols based on the evidence:
Acute rescue: a single big dose (~0.2-0.35 g per kg body weight — so 15-25g for most adults) right before a stress event like a red-eye or all-nighter. Split across 30 min with water.
Chronic loading: 10-20g/day split into 4-5g doses through the day, for at least a few weeks. Lets your brain creatine actually rise to the ~10% ceiling.
Standard 5g/day is fine for muscle and won't hurt — just don't expect it to do anything cognitive on its own.
this was super helpful thank u
🙏going to send this to my dad
Anytime. Tell him to talk to his doctor before stacking anything on top of his current meds — kidney disease, blood thinners, and a few other conditions need a closer look.
Read Sun, May 17 · 9:58 AM