I'm going to make a bold claim, and I want you to sit with it for a second before you push back.

Creatine is the single most underrated supplement in existence. Not the most popular. Not the most hyped. The most underrated. Because the thing most people think creatine does — help you lift heavier in the gym — is arguably the least interesting thing about it.

Your brain is burning through creatine right now, as you read this sentence.

And almost nobody is talking about it.

Here is a number that changed how I think about supplementation: your brain is roughly 2 percent of your body weight but chews through 20 percent of your total energy output. Twenty percent. It is, pound for pound, the most energy-hungry organ you own, and every single joule of that energy arrives in the same currency — adenosine triphosphate. ATP.

You know what regenerates ATP?

Creatine. That is its entire job. It donates a phosphate group to spent ADP and recycles it back into usable ATP. We have known this about muscle tissue for decades. What took longer to appreciate is that neurons run on the exact same biochemistry. They need rapid ATP turnover to fire, to maintain membrane potentials, to synthesize neurotransmitters. Creatine phosphate acts as a local energy reservoir your brain taps when demand spikes — during complex problem-solving, during stress, during sleep deprivation.

And unlike your quads, which store plenty of creatine, your brain's reserves are relatively limited. They can become rate-limiting.

Dechent and colleagues showed back in 1999 using magnetic resonance spectroscopy that supplementation raises brain creatine concentrations by 5 to 10 percent. Lyoo's group confirmed it in 2003. Five to ten percent might not sound like much until you remember that this is an organ perpetually running near its energy ceiling. A 5 percent buffer in the brain is not trivial. It is the difference between your prefrontal cortex working and your prefrontal cortex sputtering.

So what happens when you actually give the brain more creatine to work with?

This is where it gets good. And honestly, this is the part that made me start recommending creatine to people who have never stepped inside a gym.

Creatine has over 700 human trials behind it — more than any other sports supplement in history. More than vitamin D. More than fish oil. More than protein powder. Most of those trials focused on muscle and power output. But a growing subset has looked at cognition, and the findings are hard to ignore.

Tom McMorris and his colleagues at the University of Chichester have published some of the most practical work here. In a 2006 study in Psychopharmacology, they took subjects, gave them 5 grams of creatine per day for a week, then kept them awake for 24 straight hours. The creatine group maintained significantly better performance on complex cognitive tasks — reaction time, mood, perceived effort — compared to placebo.

They followed it up in 2007 with a more brutal 36-hour deprivation protocol.

Same results. The creatine group held together. The placebo group fell apart predictably.

The mechanism makes intuitive sense. Sleep deprivation hammers brain ATP reserves. Creatine provides a buffer.

It does not replace sleep — nothing does — but it partially offsets the cognitive cost of not getting enough. Think of it as a UPS for your brain. The power is still flickering, but the battery keeps the system running longer before it crashes.

If you are a shift worker, a new parent, anyone who travels across time zones, or honestly just a person who sometimes has a terrible night and still needs to function the next morning, this data is worth knowing. And it is probably the most immediately practical finding in the entire creatine-cognition literature.

Then there is the vegetarian study, and this is the one that really made me pay attention.

Caroline Rae and her team published this in the Proceedings of the Royal Society B in 2003. They took 45 young adult vegetarians and vegans, gave them 5 grams of creatine per day for six weeks, and tested their working memory and processing speed.

The results were not subtle.

Working memory improved significantly on backward digit span tasks. Processing speed on Raven's Progressive Matrices jumped roughly 15 to 20 percent.

Think about that for a second. A supplement that costs about a dime a day improved processing speed by 15 to 20 percent in six weeks.

Now, why vegetarians specifically? Because they get essentially zero creatine from their diet. Omnivores pick up 1 to 2 grams daily from meat and fish. Vegetarians start from a lower baseline, so supplementation produces a larger relative bump — it is easier to detect the signal.

But this does not mean creatine only works for plant-based eaters. It means that population gave researchers the cleanest window into what creatine does in the brain when you go from not-enough to enough. The effect exists in omnivores too. It is just harder to measure because the starting point is higher. You are topping off a tank that is already half full versus filling one that is nearly empty.

A 2018 meta-analysis by Avgerinos and colleagues in Experimental Gerontology pooled data across six randomized controlled trials and found that creatine supplementation improved short-term memory and reasoning across the board, with the strongest effects in older adults and people under stress.

That pattern — biggest benefits in populations where energy reserves are lowest — keeps showing up. It mirrors the muscle data perfectly.

Speaking of aging.

Eric Rawson has published several studies looking at creatine and cognitive function in older adults. A 2008 trial showed that creatine supplementation improved long-term memory, forward number recall, and spatial memory in adults over 60. His 2011 review with Venezia concluded that the cognitive effects are most robust in aging populations and during metabolic stress.

As the brain ages, it becomes more vulnerable to energy deficits. Mitochondrial function declines. ATP production slows. The margin between having enough energy and not having enough gets thinner every year.

Creatine's role as a buffer becomes proportionally more valuable in exactly this context. This is not speculative hand-waving. This is the same mechanism we see in muscle tissue, playing out in neurons. And it suggests something important: the people who stand to benefit most from creatine supplementation are not twenty-five-year-old athletes. They are your parents. Your grandparents. The people who have never once set foot in a supplement store.

The neuroprotection angle is earlier-stage, but it is where the military started paying attention.

Sullivan and colleagues demonstrated in 2000 that creatine supplementation reduced cortical brain damage by up to 50 percent following traumatic brain injury in animal models. Sakellaris published a human study in 2006 looking at children and adolescents with TBI — the creatine group showed reduced post-traumatic amnesia, shorter ICU stays, and better disability scores. Small study, not blinded, needs replication. But the effect sizes were large, and the Department of Defense has since funded multiple investigations into creatine for TBI prevention and recovery.

When the DoD starts spending money on a supplement, it is worth asking why.

There is also early but intriguing data on depression. In-Kyoon Lyoo published an RCT in the American Journal of Psychiatry in 2012 showing that adding 5 grams of creatine per day to SSRI treatment produced faster and larger improvements in depression scores compared to SSRI plus placebo in women with major depressive disorder. Neuroimaging studies have shown that depressed brains exhibit altered phosphocreatine levels — restoring that energy buffer may support treatment response.

This is not a standalone treatment. Nobody should use it as one. I want to be clear about that.

But as an adjunct to standard therapy, the early signal is genuinely encouraging. And given creatine's safety profile and cost, the barrier to trying it is essentially zero.

So let me tally this up.

Cognitive protection under sleep deprivation. Memory and processing speed improvements. Neuroprotection research that the military is funding. Depression adjunct data. Age-related cognitive decline mitigation.

All from a supplement with over 700 trials and one of the cleanest safety profiles in existence. All from something that costs about as much as a stick of gum per day.

Let me address the safety thing directly, because I still hear people repeat the kidney myth.

It is a myth.

Antonio and colleagues published a 2017 review in the Journal of the International Society of Sports Nutrition examining every clinical trial on creatine and renal function. No adverse effects. None. Including studies lasting up to five years. The International Society of Sports Nutrition's position stand, authored by Kreider and 13 other researchers, explicitly states that creatine monohydrate is safe for healthy populations in both short-term and long-term use.

If you have pre-existing kidney disease, talk to your doctor. If your kidneys are healthy, this is a solved question. Move on.

One thing that does happen: creatine raises serum creatinine levels, which is a marker doctors use to estimate kidney function. This is not because your kidneys are struggling. It is because creatine naturally breaks down into creatinine, and more creatine means more creatinine in your blood.

If your doctor sees an elevated creatinine number and you are supplementing with creatine, just tell them. Context matters. The kidneys are fine.

People also ask about water retention and bloating. Creatine does increase intracellular water — inside the muscle cell. This is actually beneficial and may support protein synthesis. The "puffy" look people complain about usually comes from slamming 20-gram loading doses with inadequate water. At 3 to 5 grams per day with normal hydration, this is a non-issue for the vast majority of people. Drink your water. You should be doing that anyway.

And while I am debunking things — no, creatine is not a steroid. I cannot believe I have to type that sentence in 2026, but here we are.

It is a naturally occurring compound made from three amino acids: arginine, glycine, and methionine. Your liver produces about a gram of it every day. You eat it every time you have a steak or a piece of salmon. It is closer to a B vitamin than it is to testosterone. It is legal in every sport, tested in every context, and permitted by every governing body on the planet.

The fact that this myth persists tells you how deep the branding problem goes. Creatine got lumped in with the sketchy bodybuilding supplements of the 1990s and it never fully escaped that association. The science moved on. The public perception did not.

I was explaining all of this to my wife last week — the brain energy thing, the vegetarian study, the TBI research — and she looked at me and said, "So you're telling me it makes you smarter and it costs a dime?" And honestly, that is a pretty accurate summary. She now takes it too.

On the topic of forms: buy creatine monohydrate. Period.

Every other form — HCl, buffered, ethyl ester — is a marketing story dressed up as science.

Creatine HCl claims better solubility. True, but irrelevant, because monohydrate already absorbs at close to 100 percent. You do not need a more soluble version of something that already dissolves just fine. Buffered creatine, sold as Kre-Alkalyn, was directly compared to monohydrate in a head-to-head trial by Jagim and colleagues in 2012. No advantage. Zero. You are paying three to five times more for a form that does not perform better in any measurable way.

Creatine ethyl ester is even worse — it actually degrades into creatinine in the gut faster than monohydrate, meaning you absorb less of the active compound. You are literally paying more to get less.

Save your money.

Dosing is simple. Three to five grams per day. Every day. You do not need a loading phase — loading saturates muscle stores faster, but brain uptake is slow regardless. MRS imaging suggests it takes four to eight weeks of consistent daily supplementation to meaningfully raise brain creatine levels.

So the protocol is not complicated. It is just patient.

Take your 5 grams, stir it into whatever you are drinking, and do it again tomorrow. And the next day. Give it six to eight weeks before you evaluate whether you notice anything cognitive.

This is not a pre-workout you feel in thirty minutes. It is infrastructure. You are slowly raising the baseline energy capacity of your brain, one scoop at a time. The effects are not dramatic on any given Tuesday. They are cumulative. They show up as slightly sharper thinking under stress, slightly better recall when you are tired, slightly more resilience when life gets demanding. The kind of thing you do not notice until you stop.

Timing does not matter much. Morning, evening, with food, without food — the research shows no meaningful difference. Consistency is the only variable that matters. Pick a time, make it a habit, and forget about it.

I personally use Thorne Creatine because it is NSF Certified for Sport, which means independent third-party testing for purity and banned substance contamination. Creatine is a commodity supplement, which means the market is flooded with cheap options of varying quality. Third-party certification eliminates guesswork. Thorne's version is micronized monohydrate — dissolves clean, no grit, no taste. At roughly ten cents a day, it is the highest-value supplement I take. It's also available on Amazon.

Here is where I will plant my flag.

I think every adult should be taking creatine monohydrate. Not just athletes. Not just gym people. Everyone.

The cognitive benefits alone justify it, even if you never touch a barbell. The safety data is decades deep. The cost is negligible. The mechanism is well understood. And the populations that benefit most — older adults, people under stress, those with poor sleep, vegetarians — are also the populations least likely to be taking it, because they have been told it is a gym supplement.

I take 5 grams every morning in my water. Have for years. It is the one supplement I would keep if I could only keep one, and it is not close. Not because the effect is the most dramatic thing I have ever felt — it is not — but because the risk-to-reward ratio is so absurdly lopsided that not taking it makes no sense.

That framing needs to die. It is outdated, it is inaccurate, and it is keeping people from one of the lowest-risk, highest-reward interventions available.

Creatine is brain fuel that also happens to help your muscles. Five grams a day. Monohydrate. Consistently.

It might be the cheapest cognitive insurance policy you can buy. The fact that it costs less than your morning coffee makes it, quite literally, a no-brainer.

So here is my question: if the cognitive data is this strong, the safety data is this clean, and the cost is this low — why is creatine still sitting in the bodybuilding aisle instead of next to the multivitamins? What would it take to change your mind about it?

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