Creatine is the most popular sports supplement in the world, and also one of the most mythologized. Ask around a gym and you will hear confident claims: it destroys your kidneys, it makes your hair fall out, it causes cramps, it is basically a steroid. Nearly all of this is wrong. Creatine monohydrate is also the most studied sports supplement in existence, with hundreds of trials and decades of real-world use behind it.
So is creatine safe? For healthy people, the evidence says yes, emphatically. The International Society of Sports Nutrition (ISSN) position stand (Kreider et al., 2017, Journal of the International Society of Sports Nutrition) concludes that creatine is safe and effective, and long-term studies show no harm to kidneys or liver. But the myths persist because they contain grains of distorted truth. This article separates them: kidneys, hair loss, long-term use, proper dosing, and who should actually be cautious.
Creatine: Myth vs Fact
Tap any card to flip between the gym folklore and what the article reports the evidence says.
What Creatine Is and How It Works
Creatine is a compound your body makes from amino acids and also gets from meat and fish. It is stored in muscle as phosphocreatine, which rapidly regenerates ATP, the energy currency of intense muscular effort. Supplementing with 3 to 5 grams daily saturates muscle creatine stores over a few weeks, which translates to more strength, more power, and slightly more lean mass when combined with resistance training. It is not a stimulant and not a hormone. It is a fuel-system top-up.
“So is creatine safe? For healthy people, the evidence says yes, emphatically.”
Is Creatine Safe for Your Kidneys?
This is the biggest myth, and it has a traceable origin. Creatine breaks down into creatinine, a waste product that doctors measure in blood tests to estimate kidney function (GFR). Supplementing creatine slightly raises creatinine levels, which can make a lab value look worse without any actual change in kidney function. The marker moved; the kidneys did not.
When researchers measure kidney function properly, with methods that are not confounded by creatinine, creatine shows no harm. The longest-duration safety work comes from Poortmans and colleagues, who studied creatine users for up to five years and found no impairment of renal function. Kreider and colleagues (2003, Molecular and Cellular Biochemistry) followed 98 Division IA college football players for up to 21 months: after a five-day loading phase of 15.75 g/day, the players took about 5 g/day for the rest of the study, and a 54-item panel of blood and urine markers showed no significant differences between creatine users and non-users in any measure of clinical health status, including kidney and liver markers.
The ISSN position stand (Kreider et al., 2017) reviewed this full literature and concluded that creatine supplementation at recommended dosages does not damage kidneys or liver in healthy individuals. This has been tested in athletes, older adults, and clinical populations. The verdict is consistent.
The one legitimate caveat: if you already have kidney disease, the rules change. Anyone with diagnosed renal impairment, or taking medications that stress the kidneys, should talk to their doctor before supplementing. That is not an indictment of creatine; it is standard caution for a compromised organ.
“The marker moved; the kidneys did not.”
Does Creatine Cause Hair Loss?
This myth traces to a single small 2009 study by van der Merwe and colleagues. Twenty college-aged rugby players took 25 g/day of creatine for seven days, followed by 5 g/day for 14 more days, and their serum dihydrotestosterone (DHT), a hormone linked to male pattern baldness, rose by 56% after the seven-day loading phase and stayed about 40% above baseline after the maintenance phase. That is the entire evidence base: 20 men, three weeks, a hormone measurement.
The study has never been replicated, it did not measure hair loss at all, and the DHT increase stayed within normal physiological ranges. In the years since, no randomized trial found that creatine causes hair loss or accelerates balding. And in 2025, a randomized controlled trial published in the Journal of the International Society of Sports Nutrition finally measured what actually matters: 38 resistance-trained men took creatine for 12 weeks, and researchers found no effect on hair density, follicle count, or DHT levels.
The theoretical chain (creatine raises DHT, DHT causes baldness, therefore creatine causes baldness) skips the only step that matters: evidence that it actually happens. It does not exist. If you are genetically prone to hair loss, you will lose hair with or without creatine; if you are not, creatine will not change that. This myth survives on gym folklore, not data.
Is Creatine Safe? The Short Answer
The quick verdict: Creatine monohydrate at 3 to 5 grams daily is one of the most studied supplements ever, with no credible evidence of kidney damage in healthy adults. The hair scare traces to one 2009 study of 20 rugby players that measured a blood hormone, never a hair, and was never replicated. A 2025 trial that measured hair directly found no effect.
2026 Update: The Hair Trial That Actually Measured Hair
This deserves a clean retelling, because nearly every “creatine causes baldness” article on the internet is built on one paper.
The 2009 study: van der Merwe, Brooks, and Myburgh gave 20 college-aged rugby players a creatine loading phase (25 g/day for 7 days) followed by a maintenance phase (5 g/day for 14 days) in a crossover design, and measured blood hormones (Clinical Journal of Sport Medicine, PMID 19164832). Testosterone did not change. DHT rose 56 percent after the loading week and stayed about 40 percent above baseline during maintenance. Every value stayed inside the normal range for healthy men. Nobody counted a follicle. Nothing about hair was measured at all.
What came next: the result was never replicated. And in 2025, a twelve-week randomized, placebo-controlled trial in resistance-trained men measured testosterone, free testosterone, DHT, and hair directly: hair count, density, and participant-reported shedding. It found no significant difference in any hormone or any hair measure between the creatine and placebo groups (Lak et al., Journal of the International Society of Sports Nutrition, 2025, as reported by Blue Headline and Acibadem).
The honest summary: a short-term blood hormone blip in one small, unreplicated study is not a hair loss finding. If you are still nervous, skip the loading phase and take 3 to 5 grams daily. That is the dose used in the long-term safety research, and it is the dose I take.
Long-Term Use: What Decades of Data Show
Creatine has been studied for longer continuous periods than almost any other supplement. The Kreider 2003 trial ran up to 21 months in college football players, Poortmans and colleagues studied users for up to five years, and the ISSN’s 2017 position stand, updated as the literature grows, continues to affirm its safety for long-term use in healthy individuals.
Two related myths deserve burial here. First, cramping and dehydration: early speculation suggested creatine caused cramps, but controlled studies actually find creatine users experience fewer cramps and heat-related issues, likely because better-hydrated muscle cells handle stress better. Second, the idea that you must cycle off creatine periodically has no evidentiary basis; continuous daily use maintains saturation safely.
Beyond muscle, research is exploring creatine for brain health: small trials suggest cognitive benefits under sleep deprivation and mental stress, and there is interest in older adults, where creatine plus resistance training supports muscle and possibly bone. This work is preliminary but intriguing, and it all rests on the same safety foundation.
Related reading: do nootropics work — our evidence review puts creatine’s cognitive data alongside caffeine, L-theanine, and the rest of the nootropics field.
My Own Creatine Line Item: Price Tracking 2021 to 2026
To keep this honest, here is my creatine receipt history. I take Optimum Nutrition Micronized Creatine Powder, 5 g daily. It is part of the daily stack I price-tracked in my supplement stack cost breakdown, 2021 vs 2026. Creatine had the wildest price ride of anything in that stack: it spiked roughly 150 percent during the supply crunch, then crashed back below its 2021 price. Today it is one of the cheapest proven supplements per effective dose on the shelf.
That matters for the safety conversation too. When a supplement is this cheap, the fear-mongering has to be louder to move you off it. Judge it by the decades of data, not the price tag in either direction. For the bigger picture on which supplements earn their money, read my evidence review of whether supplements are a waste of money.
The Creatine Evidence at a Glance
Six headline questions from the article, answered in one line each.
What it is
A compound your body makes from amino acids, stored in muscle as phosphocreatine to recharge ATP during short bursts of effort. Red meat and fish provide some; the article reports vegetarians start lower and respond even better.
Kidneys
Creatinine rises on creatine, which can make a lab value look worse, but trials up to five years and the ISSN position stand find no harm to kidney function in healthy people.
Hair loss
One small 2009 rugby study found higher DHT but never measured hair loss and was never replicated. In 15 plus years, no randomized trial has found creatine causes hair loss.
Long-term use
Studied for longer continuous periods than almost any supplement, including a five year trial, with no adverse effects on kidney, liver, or general health markers.
How to take it
3 to 5 grams of creatine monohydrate daily, the cheap unflavored powder. Optional 20 grams per day for 5 to 7 days loads faster, but daily 3 to 5 grams reaches saturation within a month. No cycling needed; timing barely matters.
Who should be cautious
People with pre-existing kidney disease, teens (talk to a pediatrician), and pregnant or breastfeeding women. Everyone else: it is among the safest, most studied, most effective supplements ever tested.
