Creatine: The Most Underrated Supplement for Women, Athletes, and Your Brain

The Supplement Everyone Thinks They Know

Ask most people what creatine is for and they'll say the same thing: big guys at the gym trying to get bigger. It's been lumped in with protein powders and pre-workouts — a bro supplement, a bulking tool, something that doesn't apply to you if you're a woman, a runner, a cyclist, or someone who just wants to feel sharp and energetic.

That reputation is decades out of date.

Creatine monohydrate is one of the most extensively researched supplements in human nutrition. There are over 500 peer-reviewed studies on its effects, and the evidence base has expanded far beyond the weight room. Cognitive performance. Mood and depression. Neuroprotection. Bone density. Hormonal health in women. The research is compelling, consistent, and largely ignored in mainstream health conversations.

At PeakLAB, creatine is one of the supplements I recommend most frequently — and not just to athletes. Here's why.

What Creatine Actually Does in Your Body

Creatine is a naturally occurring compound made primarily in the liver and kidneys from the amino acids arginine, glycine, and methionine. About 95% of the body's creatine is stored in skeletal muscle, with the remaining 5% distributed in the brain, heart, and other tissues.

Its primary role is in the phosphocreatine energy system — the fastest pathway your body has for regenerating ATP (adenosine triphosphate), the molecule that powers virtually every cellular process. When you need rapid, high-intensity energy — lifting a heavy weight, sprinting, climbing a steep trail — your body draws on phosphocreatine stores to rapidly resynthesize ATP. The more creatine you have available, the more fuel you have for those high-demand moments, and the faster you recover between efforts.

Supplementing with creatine monohydrate increases the total creatine and phosphocreatine content in your muscles by approximately 20–40%, depending on your baseline levels. This is the mechanism behind its well-established benefits for strength, power output, and high-intensity exercise performance.

But the brain also runs on ATP — and it turns out the brain benefits from creatine in ways that are only now being fully appreciated.

The Athletic Case: What the Evidence Actually Shows

Let's start with what creatine is best known for, because the evidence here is exceptionally strong. A 2017 meta-analysis published in the Journal of Strength and Conditioning Research examined 22 randomized controlled trials and found that creatine supplementation combined with resistance training produced significantly greater gains in muscle strength and lean mass compared to training alone. The effect size was consistent across age groups, training experience levels, and both sexes.

The performance benefits are not limited to pure strength sports. Creatine improves performance in any activity that involves repeated high-intensity efforts with short recovery periods — interval training, team sports, CrossFit, cycling sprints, and heavy lifting all fall into this category. It also accelerates recovery between sessions by reducing exercise-induced muscle damage and inflammation, meaning you can train harder and more frequently without the same degree of breakdown.

For endurance athletes, the picture is more nuanced. Creatine does not meaningfully improve sustained aerobic output (VO2 max, marathon pace), but it does improve performance in the high-intensity surges that occur within endurance events — the final kick, the climb, the sprint to the finish. For masters athletes in particular, who experience accelerated muscle loss with age, the muscle-preserving effects of creatine are clinically significant independent of performance goals.

The Cognitive Case: Your Brain Runs on Creatine Too

This is where the conversation gets genuinely exciting — and where most people are surprised.

The brain is one of the most metabolically demanding organs in the body, consuming roughly 20% of your total energy despite representing only 2% of your body weight. It relies heavily on the phosphocreatine system to maintain ATP levels during periods of high cognitive demand. When brain creatine stores are depleted — by sleep deprivation, mental fatigue, stress, or simply the natural decline that comes with aging — cognitive performance suffers measurably.

Supplemental creatine increases brain creatine concentrations, and the cognitive effects are well-documented. A 2022 meta-analysis in Nutrients reviewed 15 randomized controlled trials and found that creatine supplementation significantly improved memory and intelligence/reasoning in healthy adults, with the largest effects seen in older adults and in individuals under conditions of metabolic stress (sleep deprivation, oxygen restriction, intense cognitive load).

The specific domains most consistently improved include working memory (the ability to hold and manipulate information in real time), processing speed, and executive function — the higher-order cognitive skills involved in planning, decision-making, and mental flexibility. These are exactly the cognitive capacities that tend to decline first with aging and stress.

There is also emerging evidence that creatine may have a role in mood regulation and depression. A 2021 study in Bipolar Disorders found that creatine supplementation augmented the effects of antidepressant therapy in women with treatment-resistant depression. The proposed mechanism involves creatine's role in maintaining energy availability in brain regions involved in mood regulation, particularly the prefrontal cortex. While this research is still developing, it adds another dimension to creatine's potential beyond physical performance.

The Women's Health Case: Why This Matters More Than You Think

Here is the most underappreciated story in the creatine literature: women may benefit from creatine supplementation more than men, and yet women are dramatically underrepresented in the research and dramatically under-informed about this supplement.

The reason women may benefit more comes down to baseline biology. Women naturally have lower resting creatine stores than men — approximately 70–80% of male levels — due to differences in muscle mass and dietary intake (creatine is found primarily in red meat and fish, and women on average consume less of both). This means women are starting from a lower baseline and have more room to benefit from supplementation.

The hormonal dimension adds another layer. Estrogen and progesterone both influence creatine transport and metabolism. During the luteal phase of the menstrual cycle (the two weeks before menstruation), when progesterone is elevated and many women experience fatigue, brain fog, and mood changes, creatine stores are naturally lower. Supplementation during this phase may help buffer some of these symptoms by maintaining brain energy availability.

The perimenopause and menopause transition is where the evidence becomes particularly compelling. As estrogen declines, women experience accelerated muscle loss (sarcopenia), reduced bone density, increased cognitive symptoms, and mood disruption. Creatine addresses several of these simultaneously. A 2021 review in Nutrients specifically examining creatine in women found benefits for muscle mass and strength, bone density (particularly when combined with resistance training), cognitive function, and mood — all domains directly relevant to the menopausal transition.

For women who are not yet in perimenopause, creatine still offers meaningful benefits for body composition, athletic performance, cognitive sharpness, and long-term neuroprotection. The idea that creatine is a male supplement is not just outdated — it is actively doing women a disservice.

Common Questions and Misconceptions

Will creatine make me bulky?

This is the most common concern I hear from women, and it deserves a direct answer: no. Creatine does not cause the kind of muscle hypertrophy associated with anabolic steroids or extremely high-volume resistance training. What it does cause in the first week or two of supplementation is an increase in intramuscular water retention — your muscles store more water alongside the creatine, which can add 1–3 pounds on the scale. This is not fat, it is not permanent, and it is actually associated with improved muscle function and recovery. For most women, the visible effect is muscles that look slightly fuller and more defined, not bigger.

Is creatine safe for long-term use?

Yes. Creatine monohydrate has one of the strongest long-term safety profiles of any supplement. Studies following subjects for up to five years of continuous use have found no adverse effects on kidney function, liver function, or any other organ system in healthy individuals. The concern about kidney damage is a persistent myth that has been thoroughly refuted in the research literature. The one caveat: individuals with pre-existing kidney disease should discuss creatine use with their physician before starting.

Do I need to load creatine?

Loading protocols (20g/day for 5–7 days) do saturate muscle creatine stores faster, but they are not necessary. A standard maintenance dose of 3–5g per day will reach the same saturation point within 3–4 weeks and is better tolerated by most people. I generally recommend starting with 3–5g daily and skipping the loading phase entirely.

When should I take it?

Timing matters less than consistency. The research suggests a slight advantage to taking creatine close to your workout (either pre or post), but the most important thing is simply taking it every day. It accumulates in your tissues over time — missing a day occasionally is not a problem, but inconsistent use will blunt the benefits.

What to Look for in a Creatine Supplement

Not all creatine supplements are created equal. The form matters, the quality of manufacturing matters, and the absence of unnecessary additives matters.

Creatine monohydrate is the gold standard. It is the most studied form by a significant margin, the most bioavailable, and the least expensive. Other forms — creatine HCl, buffered creatine, creatine ethyl ester — are marketed as superior but have not demonstrated meaningful advantages over monohydrate in head-to-head trials. Save your money and stick with monohydrate.

Third-party testing is non-negotiable. Supplement manufacturing in the United States is not regulated by the FDA to the same standard as pharmaceuticals, which means the label may not accurately reflect what's in the product. Look for supplements that carry NSF Certified for Sport, Informed Sport, or USP certification — these indicate independent verification of purity and label accuracy.

Micronized creatine (creatine monohydrate that has been processed into smaller particles) dissolves more easily in water and is generally better tolerated by people who experience GI discomfort with standard creatine monohydrate.

The product I recommend to my patients — and use myself — is available through my Fullscript dispensary. It meets all of these criteria: pharmaceutical-grade creatine monohydrate, third-party tested, micronized for easy mixing, and free of unnecessary fillers and artificial additives.

The Bottom Line

Creatine monohydrate is not a niche supplement for competitive bodybuilders. It is one of the most evidence-backed, broadly applicable, and underutilized tools in the performance and longevity medicine toolkit — particularly for women, older adults, and anyone who values cognitive sharpness alongside physical health.

The evidence supports its use for building and maintaining muscle, improving high-intensity athletic performance, sharpening memory and executive function, supporting mood, and protecting the brain against age-related decline. It is safe, inexpensive, and well-tolerated by the vast majority of people.

If you are a woman who has been told creatine is not for you — or if you have simply never considered it because you don't think of yourself as an athlete — I would encourage you to reconsider. Your muscles and your brain will thank you.

As always, if you have questions about whether creatine is appropriate for your specific situation, or if you want to discuss a comprehensive supplement and performance protocol, I'd love to connect. A discovery call is the best place to start.