Creatine Isn't Just for Gym Bros Anymore

For decades, creatine had exactly one demographic: guys in tank tops scooping powder into a shaker bottle. Now it turns up in menopause podcasts, longevity newsletters, gummy form at the checkout counter, and conversations between people who have never touched a barbell. Your mother-in-law might be taking it.

Some of that shift is genuine science catching up. Creatine is one of the most heavily studied compounds in all of nutrition, and the research has expanded well past athletic performance into aging, brain energy, and plant-based diets. Some of it is marketing filling in the gaps with confidence the evidence has not earned.

So here is the honest version. What creatine actually is, how much you already get from food, what the research genuinely supports, what it does not, and how to tell whether any of it applies to you.

What Creatine Actually Is

Creatine is not a drug, a hormone, or a steroid. It is a compound your body makes on its own and also eats — a naturally occurring part of human metabolism that happens to be sold in a tub.

Its job is energy timing. Muscle cells run on ATP, but they only hold a few seconds' worth at a time. Creatine is stored in muscle mostly as phosphocreatine, which acts as a rapid-recharge buffer: when ATP is spent during a hard effort, phosphocreatine donates a phosphate group and regenerates it almost instantly. That is why creatine matters most for short, intense, repeated efforts — a heavy set, a sprint, a flight of stairs taken quickly — rather than for endurance.

Your liver and kidneys synthesize creatine from the amino acids arginine and glycine. According to the International Society of Sports Nutrition's position stand on creatine, the body needs to replenish roughly 1 to 3 grams per day to hold normal stores steady, and about half of that daily need is met by food. The rest you make yourself.

Muscle has a ceiling. The position stand puts the total creatine pool at around 120 mmol per kilogram of dry muscle for a 70-kilogram person, with an upper storage limit of about 160 mmol/kg in most people. That ceiling is the single most useful fact in this whole topic: you cannot keep pouring creatine in and get more effect. Once the tank is full, the excess is simply excreted. This is also why the difference between a $15 tub and a $60 tub is mostly packaging.

How Much You Already Get From Food

Creatine in the diet comes almost entirely from muscle tissue — meat and fish. The ISSN position stand gives a useful benchmark: a pound of uncooked beef or salmon supplies roughly 1 to 2 grams of creatine.

Two things follow from that. First, if you eat meat or fish most days, you are already getting a meaningful share of your daily creatine turnover from dinner, and your muscle stores are probably sitting reasonably close to their natural set point. Second, dairy and eggs contribute very little, and plants contribute essentially none — which is where the picture changes sharply for some people.

The Strongest Evidence: Muscle, Strength, and Training

This is the part that has held up for thirty years. When creatine supplementation is paired with resistance training, people tend to gain slightly more lean mass and strength than they would from training alone. The ISSN describes creatine monohydrate as the most effective nutritional supplement currently available to athletes for increasing high-intensity exercise capacity and lean body mass during training. That is a strong claim, from a body of literature large enough to support it.

But two honest caveats belong right next to it.

The first is that the effect is a multiplier on training, not a substitute for it. Creatine without resistance training does very little for muscle.

The second is that not every well-run trial finds an added benefit. A 2025 randomized trial in Nutrients followed 63 adults (34 women, 29 men, mean age 31) through a 7-day creatine wash-in followed by 12 weeks of resistance training, using 5 grams a day. During the wash-in phase — before any training started — the creatine group gained 0.51 kg more lean body mass than controls, an effect the authors attributed largely to fluid rather than tissue. Then both groups gained about 2 kg of lean mass over the training block, with no difference between them (p = 0.71). The authors suggested a higher maintenance dose might be needed to see a training effect. It is worth noting the study had no placebo group, which limits how far the result can be pushed. But it is a useful corrective to the idea that creatine reliably stacks muscle on top of a good program in young, healthy people.

The Aging Case: Where It Gets More Interesting

The argument that has pulled creatine out of the gym is not really about performance. It is about still being able to get out of a chair unassisted at 80.

Age-related muscle loss is the real target, and here the pooled evidence is encouraging. A meta-analysis by Chilibeck and colleagues combined 22 randomized controlled trials covering 721 older adults (mean ages across studies ranged from 57 to 70). Participants who supplemented with creatine while resistance training gained 1.37 kg more lean tissue mass than those training on placebo (95% CI 0.97 to 1.76 kg, p < 0.00001), with modest but significant advantages in chest press strength (SMD 0.35, p = 0.0002) and leg press strength (SMD 0.24, p = 0.01).

A more recent and more conservative 2025 systematic review in the European Review of Aging and Physical Activity, restricted to 8 trials and 482 participants aged 50 and over, found smaller effects: a significant benefit for lean tissue mass (SMD 0.27, p = 0.03) and a borderline one for lower-limb strength (SMD 0.29, p = 0.05), with upper-limb strength not reaching significance. The authors graded the certainty of the evidence as moderate, flagged high dropout rates across the included trials, and noted the effects looked strongest in interventions of 32 weeks or less.

Put those together and you get a fair summary: for older adults who are already strength training, creatine appears to add a small but genuine amount of lean tissue and strength. The training is doing most of the work. If you are not lifting anything, the supplement is largely beside the point — which is also the honest conclusion of our post on protein at every meal after 60.

The Brain Claims: Real Signal, Overstated Story

Your brain is metabolically expensive and uses the same phosphocreatine buffering system your muscles do, so the theory behind cognitive benefits is not fanciful. The evidence, though, is genuinely mixed — and much weaker than the current wave of "creatine for your brain" content implies.

A 2024 systematic review and meta-analysis pooled 16 randomized controlled trials with 492 adults aged roughly 21 to 76, using doses from 3 to 20 grams a day for periods ranging from one week to 18 months. It found a significant improvement in memory (SMD 0.31, 95% CI 0.18 to 0.44, p < 0.00001) and faster completion times on attention and processing-speed tasks. But accuracy scores on those same attention and processing-speed measures did not improve, and neither executive function (p = 0.12) nor overall cognitive function (p = 0.22) reached significance. The authors flagged small samples, inconsistent testing methods, and thin evidence in older adults. (A later corrigendum clarified some translated wording without changing any of the numbers.)

Regulators looking at the same literature have been less impressed. In November 2024, the European Food Safety Authority evaluated a proposed health claim that "daily creatine supplementation can contribute to improved cognitive function" at 3 grams a day for healthy adults. After assessing 23 human intervention studies, the panel concluded that "a cause-and-effect relationship has not been established between the consumption of creatine and an improvement in cognitive function in one or more of its domains." Notably, the panel observed that effects seen at very high short-term doses did not carry over to the 3-gram daily dose actually being proposed.

That last detail explains the one place where the brain evidence looks genuinely strong: extreme conditions, extreme doses. A 2024 crossover trial in Scientific Reports gave 15 young adults a single dose of 0.35 g/kg of creatine — roughly 25 grams for a 70-kilogram person — during 21 hours of sleep deprivation. Compared with placebo, creatine improved word memory by about 10%, sped up processing on language, logic, and numeric tasks by 16 to 29%, improved reaction speed on a vigilance test, and reduced self-reported fatigue by around 8%. Effects appeared 3.5 hours after dosing, peaked at roughly 4 hours, and were still present 9 hours later.

That is a striking result. It is also 15 people, one night, and a dose five times the normal daily amount. It supports the idea that creatine helps a brain running on an energy deficit. It does not support the idea that 5 grams in your morning coffee will make you sharper on an ordinary Tuesday. If your cognition problem is that you slept five hours, the intervention with the best evidence is still sleep — and, secondarily, managing what a short night does to your appetite the following day.

Vegetarians: The Group With the Most Room to Move

If creatine comes almost exclusively from meat and fish, people who eat neither are running on their own synthesis alone. The research bears that out.

The ISSN position stand reports that vegetarians tend to have lower intramuscular creatine stores — around 90 to 110 mmol/kg of dry muscle, against a typical 120 — and may therefore see larger gains from supplementation. A systematic review comparing vegetarians and omnivores across nine studies found vegetarians had lower total creatine in the vastus lateralis by 10 to 15%, with larger differences in plasma (about 50% lower), serum (35 to 39%), and red blood cells (27 to 50%).

Supplementation in vegetarians raised total creatine, creatine, and phosphocreatine in muscle, plasma, and red blood cells — sometimes to levels above omnivores — and was associated with increases in lean tissue mass, type II fiber area, muscular strength, endurance, and measures of memory. Two caveats: studies were mixed on whether vegetarians actually outperformed omnivores on exercise tests, and brain creatine concentrations showed no significant baseline difference between the two groups.

Still, if there is one group for whom the food-versus-supplement calculation is genuinely different, it is long-term vegetarians and vegans — the same population that has to be deliberate about B12 and iron absorption. Same principle: some nutrients are concentrated in animal foods, and a plant-based diet needs a plan for them rather than a hope.

What About Women?

Creatine marketed to women has exploded, usually built on one statistic. A 2021 review in Nutrients on creatine across the female lifespan notes that women have 70 to 80% lower endogenous creatine stores than men, and consume significantly less dietary creatine.

What almost never gets quoted is the sentence two lines later. The same review adds that women have roughly 10% higher resting intramuscular creatine concentrations than men, "which could theoretically lower their responsiveness to supplementation and require higher dosages compared to males." In other words, the dramatic 70-to-80% figure is largely about the total body pool — which tracks total muscle mass — not about muscle being creatine-starved. Per unit of muscle, women are, if anything, slightly better stocked.

That does not make creatine useless for women. The same review concludes that supplementation appears effective for strength and exercise performance in pre-menopausal women, and that post-menopausal women may see benefits in muscle size and function at higher doses (around 0.3 g/kg/day), with favorable effects on bone when combined with resistance training. It just means the "women are 80% deficient" pitch is a misread of the paper it cites, and you can safely discount any brand leaning on it.

The Practical Questions

Loading, or not?

The classic protocol is about 5 grams four times a day (roughly 0.3 g/kg) for 5 to 7 days, then 3 to 5 grams daily to maintain. But the ISSN's follow-up paper on common creatine misconceptions is blunt: "Accumulating evidence indicates that you do not have to 'load' creatine. Lower, daily dosages of creatine supplementation (i.e. 3-5 g/day) are effective for increasing intramuscular creatine stores." Loading fills the tank in a week instead of three or four. That is the whole difference.

Which form?

Creatine monohydrate. It is the form used in the overwhelming majority of the research cited above, it is the cheapest, and no alternative form has convincingly outperformed it. Gummies, buffered versions, and liquid formulas are mostly a price increase.

The water weight

This is real, and it is the most common actual side effect. The ISSN reports that creatine loading produces short-term fluid retention of roughly 0.5 to 1.0 liter, proportional to the acute weight gain people notice. The misconceptions paper adds that creatine does not increase fat mass, and that longer-term studies do not show altered total body water. If the number on the scale matters to you psychologically, know that a two-pound jump in the first week is fluid moving into muscle.

Kidneys

This is the most persistent myth in the category, and it stems from a measurement quirk. Creatine spontaneously converts to creatinine — the very marker labs use to estimate kidney function. So taking creatine can nudge your serum creatinine up without anything being wrong with your kidneys.

A 2025 systematic review and meta-analysis on creatine and kidney function found exactly that pattern: a small but statistically significant rise in serum creatinine (mean difference 0.07 µmol/L, p = 0.03) with no significant change in glomerular filtration rate. The authors concluded the increase was "likely due to metabolic turnover rather than renal impairment," with kidney function preserved. The ISSN position stand reaches the same conclusion — no compelling evidence that creatine harms renal function in healthy or clinical populations. The practical takeaway: mention creatine before a blood panel so a mildly elevated creatinine does not trigger an unnecessary workup. And if you have existing kidney disease, that is a conversation with your doctor, not a blog post.

Hair loss and cramping

The hair-loss fear traces back to one study of 16 college-aged male rugby players, which found an increase in serum DHT — a hormone associated with pattern baldness — but never measured hair loss itself. As the misconceptions paper notes, that finding has not been replicated, and intense resistance exercise on its own can raise the same androgenic hormones. The paper states that current evidence does not indicate creatine increases total testosterone, free testosterone, or DHT, or causes hair loss. The same paper concludes that experimental and clinical research does not validate the notion that creatine causes dehydration or muscle cramping.

Food First: Know What Your Week Actually Delivers

Here is the part that gets skipped in every creatine thread. Before deciding whether to add a supplement, it helps enormously to know what you are already eating.

If you have salmon twice a week, beef a couple of times, and chicken most other nights, you are close to the top of what diet can contribute, your muscle stores are likely near their natural range, and the marginal case for supplementing comes down mostly to whether you are training hard or trying to hold onto muscle in your sixties. If you eat meat once a week and lean on beans and eggs, the calculation is different. If you are fully plant-based, it is different again.

Most people genuinely do not know which of those describes them, because "I eat pretty healthy" is not data. That is the mundane, unglamorous problem Eat Well Planner is built to solve: your saved recipes and logged meals turn into an actual picture of a week. You can see how often meat and fish really appear, what your protein intake looks like day to day, and where the gaps sit — while the nutrition score and "good source of" highlights tell you what a given meal is genuinely delivering rather than what the recipe title implies. If it turns out fish shows up twice a month rather than twice a week, that is a fixable meal-planning problem, and fixing it is worth more than any powder.

Supplements make far more sense as a decision layered on top of a known baseline. They make much less sense as a hedge against not knowing.

What Is Genuinely Overhyped

Three things, specifically.

The brain claims, at normal doses. The memory finding in the meta-analysis is real, but overall cognition did not move, and EFSA reviewed 23 trials before declining to accept the claim. The impressive sleep-deprivation result used roughly 25 grams in one sitting, under extreme conditions, in 15 people. Treat "creatine for focus" as an open question, not an established benefit.

The women's-deficiency framing. The 70-to-80% figure describes total body stores, and the same review notes women have slightly higher creatine concentration per unit of muscle. Any product built on that stat is misrepresenting its own source.

The idea that more is better. Muscle saturates at roughly 160 mmol/kg of dry mass. Past that, you are paying for expensive urine.

So Who Should Actually Consider It?

Based on where the evidence is strongest rather than where the marketing is loudest:

• People doing resistance training — the best-supported use by a wide margin, though the size of the added benefit varies and the training matters far more than the supplement.
• Older adults who strength train — the meta-analyses support a small extra gain in lean tissue and strength. If you are not training yet, start there instead.
• Vegetarians and vegans — the group with genuinely lower baseline stores and the most measurable response to supplementation.
• Post-menopausal women who lift — with the caveat that the useful doses in that literature sit on the higher end.

And who probably does not need it: someone eating meat or fish most days, not strength training, hoping a scoop of powder will do something for energy or focus. For that person the evidence is thin, and the same money spent on getting fish onto the plate twice a week — or getting to bed an hour earlier — has better data behind it.

Creatine is a reasonable, cheap, unusually well-studied supplement with a real but bounded set of benefits. That is a less exciting story than the one being sold, and it is also the accurate one. Start with what is on your plate this week, then decide whether there is a gap worth filling.