Should women with PMOS take creatine? A dietitian's evidence-based review

If you've searched for creatine and PMOS recently, there's a good chance you've come away feeling more confused than when you started.

Social media is full of claims that creatine can improve everything from hormone health and fertility to brain fog, energy and body composition. Some people even suggest that every woman should be taking it, regardless of her health or fitness goals.

As a dietitian specialising in PMOS, it's one of the questions I've been asked most often over the past few months. And I completely understand why. Unlike many supplements that become popular online, creatine isn't a passing trend. It's one of the most extensively researched sports nutrition supplements available, with decades of research supporting its role in improving muscle strength and exercise performance (Smith-Ryan et al., 2021).

However, that's quite different from saying that every woman with PMOS should take it.

One of the things I often say to clients is that supplements should always have a job to do. Before deciding whether something is worth taking, I want to understand why we're considering it in the first place. Are we trying to support strength training? Improve recovery from exercise? Restore ovulation? Reduce fatigue? Those are all very different goals, and they don't all have the same evidence behind them.

That's particularly important when it comes to PMOS. Living with PMOS often means being exposed to a constant stream of advice about supplements that promise to "balance your hormones", improve fertility or reverse the condition altogether. It can be difficult to know what to believe, especially when the information sounds convincing.

My aim in this article isn't to persuade you to take creatine or to avoid it. Instead, I'd like to take you through what the research actually tells us, where the gaps in the evidence still exist, and how I interpret that evidence when advising clients in clinic.

So, should women with PMOS take creatine?

If you're looking for a quick answer, it's this:

Not routinely.

That doesn't mean creatine isn't beneficial. In fact, for some women it may be a very sensible supplement to consider. The important point is that the reason for taking it should match the evidence.

At the moment, creatine has a strong evidence base for improving muscle strength and supporting gains in lean muscle mass when combined with resistance training (Santos et al., 2021; Naddafha et al., 2026). Research exploring its effects on cognition, mood and sleep is also growing, although the findings are still emerging (Smith-Ryan et al., 2025).

What we don't currently have is good-quality evidence showing that creatine improves the core features of PMOS, such as irregular menstrual cycles, ovulation, insulin resistance or fertility.

That distinction is important.

A lack of evidence doesn't necessarily mean creatine doesn't help. It simply means we don't yet have the research needed to recommend it confidently for those outcomes.

As clinicians, we have to be careful not to confuse biological plausibility with clinical evidence. A supplement can make perfect sense in theory, but until it's been properly tested in the population we're interested in, we can't assume it will produce meaningful clinical benefits.

Why has creatine become so popular?

To understand why creatine has attracted so much attention, it helps to know a little about what it actually does.

Creatine is a naturally occurring compound synthesised from three amino acids: arginine, glycine and methionine. Around 95% of the body's creatine is stored in skeletal muscle, where it helps regenerate adenosine triphosphate (ATP), the body's immediate source of energy during short bursts of high-intensity exercise (Smith-Ryan et al., 2021).

Your body produces around one gram of creatine each day, primarily in the liver, kidneys and pancreas, and you obtain additional creatine through foods such as red meat and fish. For many people, these normal stores are perfectly adequate for day-to-day life. Supplementation simply increases the amount of creatine available within muscle, allowing some people to perform slightly more work during resistance training before fatigue develops.

Although that might not sound particularly exciting, those small improvements can accumulate over time. Completing one or two extra repetitions or lifting slightly heavier weights may eventually translate into greater improvements in muscle strength and lean muscle mass.

Historically, this is why creatine became popular within sport.

More recently, researchers have become interested in whether its effects extend beyond exercise performance. Because creatine is also found in the brain and other tissues with high energy requirements, scientists have started exploring whether supplementation could influence cognition, mood, sleep and aspects of women's health across the lifespan (Smith-Ryan et al., 2025).

It's an interesting area of research, and one that I'm following closely. However, it's also where many of the claims on social media have become disconnected from the available evidence.

Just because creatine has shown promise in one population doesn't automatically mean the same benefits will be seen in women with PMOS.

Whenever I read a new study, one of the first questions I ask myself is: "Who was actually studied?"

One of the things I pay close attention to when reading research is who the participants were. A study in healthy young men doesn't necessarily tell us what will happen in women with PMOS, just as a study in postmenopausal women can't automatically be applied to women in their twenties.

That's why, throughout the rest of this article, I'd like to look at the evidence for each of the questions I hear most often in clinic, rather than treating creatine as though it's one intervention with one simple answer.

Because the reality is much more nuanced than that.

What does the research actually tell us?

Can creatine help you build muscle?

This is where the evidence is strongest, and it's also one of the reasons creatine has remained popular for so many years.

When creatine is combined with resistance training, it consistently improves muscle strength and, over time, can contribute to modest increases in lean muscle mass (Santos et al., 2021; Naddafha et al., 2026). These improvements don't happen because creatine builds muscle on its own. Rather, it allows many people to train a little harder by improving the availability of energy during repeated, high-intensity efforts. Over weeks and months, those small improvements in training can accumulate into meaningful improvements in strength.

This distinction is important because it's easy to think of creatine as something that "works" independently. In reality, creatine enhances the adaptations that occur in response to resistance training. Without that training stimulus, the benefits are likely to be much smaller.

Although much of the early research focused on men, more recent reviews suggest women can also benefit from creatine supplementation, particularly when it is combined with a structured resistance training programme (Smith-Ryan et al., 2021).

For women with PMOS, this may be particularly relevant. Resistance training is already encouraged as part of lifestyle management because of its positive effects on metabolic health, muscle strength and insulin sensitivity. If creatine helps you get more out of that training, it could have indirect benefits. However, it's important not to confuse those indirect benefits with evidence that creatine is treating PMOS itself.

So, what does this mean if you have PMOS?

If you're already strength training consistently and your goal is to improve your performance or become stronger, creatine is one of the few supplements I'd genuinely consider discussing. If, however, you're hoping that taking creatine alone will improve your symptoms without making other lifestyle changes, the evidence simply doesn't support that.

Can creatine help with weight loss?

This is probably one of the biggest misconceptions surrounding creatine.

Despite what you may have read online, creatine is not a weight-loss supplement.

Studies haven't shown that creatine supplementation leads to meaningful reductions in body weight or body fat when taken on its own (Smith-Ryan et al., 2021).

So why do some people say it helps with body composition?

The answer lies in the difference between weight and body composition.

If creatine allows you to train more effectively and build slightly more lean muscle over time, your body composition may improve, even if the number on the scales changes very little. Muscle is metabolically active tissue and plays an important role in overall metabolic health, but these changes happen gradually and alongside consistent resistance training.

It's also worth mentioning that some people experience a small increase in body weight during the first few weeks of supplementation. This is usually due to increased water being stored within muscle cells rather than an increase in body fat (Kreider et al., 2025).

I appreciate that this can feel unsettling, particularly if you've spent years feeling frustrated by your weight. Many women with PMOS have a difficult relationship with the scales, and seeing your weight increase, even temporarily, can feel discouraging.

This is one of the reasons I encourage clients to think about progress more broadly. Improvements in strength, energy, confidence in the gym and how you feel in your body are often much more meaningful than a small fluctuation in weight.

So, what does this mean if you have PMOS?

If your main reason for taking creatine is to lose weight, I'd be cautious about your expectations. There are many benefits to resistance training, but creatine itself shouldn't be thought of as a fat-loss supplement.

Can creatine improve insulin resistance?

Insulin resistance is one of the key drivers of PMOS for many women, although not everyone with PMOS experiences it. Because of this, it's understandable that researchers have started exploring whether creatine might have a role in improving glucose metabolism.

Some studies outside of PMOS suggest that creatine, particularly when combined with exercise, may enhance glucose uptake into muscle cells (Gualano et al., 2021). From a scientific perspective, this is certainly interesting. However, biological plausibility isn't the same as clinical evidence.

At the moment, we don't have robust clinical trials demonstrating that creatine supplementation improves insulin resistance in women with PMOS. That means we can't assume that the mechanisms observed in laboratory studies or other populations will translate into meaningful improvements in symptoms.

This is a good example of why it's important to look beyond headlines. It's entirely possible for a supplement to have a plausible mechanism while still failing to produce clinically significant benefits when properly tested.

So, what does this mean if you have PMOS?

If improving insulin resistance is one of your priorities, I'd focus first on the interventions with the strongest evidence. A balanced diet, regular physical activity, resistance training, adequate sleep and addressing any underlying nutrient deficiencies remain the cornerstones of managing insulin resistance in PMOS. Creatine may eventually have a role, but the evidence isn't strong enough for me to recommend it specifically for this purpose.

Can creatine help regulate periods or improve ovulation?

This is probably the question I've been asked most often since creatine started gaining popularity on social media.

The honest answer is that, based on the evidence we have today, we simply don't know.

At the moment, there are no randomised controlled trials demonstrating that creatine supplementation improves menstrual regularity or restores ovulation in women with PMOS (Smith-Ryan et al., 2025).

Some of the confusion stems from an observational study published in 2024, which found that women with a higher dietary intake of creatine were less likely to report irregular menstrual cycles and certain reproductive health conditions (Ostojic et al., 2024).

It's an interesting finding, but it's important to interpret it carefully.

Observational studies can identify associations, but they cannot tell us whether one factor caused another. Women who consumed more dietary creatine may also have differed in many other ways, including their overall diet quality, physical activity levels or intake of other nutrients. We simply can't conclude from this study that creatine itself improved menstrual health.

To answer that question properly, we'd need intervention studies comparing creatine supplementation with a placebo in women with PMOS while measuring outcomes such as ovulation and menstrual regularity.

Those studies haven't been carried out yet.

So, what does this mean if you have PMOS?

If your goal is to restore regular periods or ovulation, I wouldn't recommend taking creatine specifically for that reason. At the moment, I'd much rather focus on interventions that have been shown to improve ovulation and menstrual function in women with PMOS.

Can creatine improve fertility, fatigue or brain fog?

These are all areas where research is evolving, and they're perhaps some of the most exciting areas for future study.

Creatine is found not only in muscle but also in the brain and other tissues with high energy demands. Researchers are exploring whether supplementation may support aspects of cognition, mood and resilience to sleep deprivation, with some early studies showing encouraging results (Smith-Ryan et al., 2025).

However, it's important to keep these findings in context.

Most of this research has been carried out in healthy adults, older adults or specific clinical populations - not in women with PMOS. At the moment, we don't have evidence that creatine supplementation improves fatigue or brain fog specifically in women with PMOS.

Although creatine has attracted interest in reproductive medicine, particularly in relation to pregnancy and foetal development, there is currently no clinical evidence demonstrating improved fertility outcomes in women with PMOS.

When I see women in clinic struggling with fatigue or brain fog, I rarely assume there's a single cause. Poor sleep, low iron stores, vitamin D deficiency, inadequate energy intake, insulin resistance, thyroid disorders and psychological stress can all contribute. Understanding what's driving those symptoms is usually much more helpful than reaching for another supplement.

So, what does this mean if you have PMOS?

The research into creatine and women's health is genuinely exciting, and I expect we'll learn much more over the next decade. At the moment, though, I'd be cautious about taking creatine solely to improve fertility, fatigue or brain fog, because the evidence simply isn't there yet.

Is creatine safe?

One of the reasons creatine has remained popular for so many years is because it has one of the strongest safety profiles of any sports nutrition supplement.

In healthy adults, creatine monohydrate has been studied extensively and is considered safe when taken at the recommended dose (Kreider et al., 2025). Despite this, there are still a number of myths that continue to circulate online, particularly around kidney health and dehydration.

Current evidence doesn't support these concerns in healthy individuals. However, that doesn't mean creatine is appropriate for everyone. If you have pre-existing kidney disease, are pregnant or breastfeeding, or have another medical condition, it's sensible to discuss supplementation with your GP or healthcare professional before taking it.

The other point I'd make is that "safe" doesn't automatically mean "necessary".

A supplement can have an excellent safety profile and still not be the right choice for you.

Which form of creatine should you choose?

If you've started looking online, you've probably realised there are countless different forms of creatine available. Creatine hydrochloride, buffered creatine, creatine gummies, creatine blends... the list goes on.

It can quickly become overwhelming.

The reassuring news is that you don't need to overcomplicate it.

The overwhelming majority of research has been carried out using creatine monohydrate, and at the moment there's no convincing evidence that the more expensive formulations provide additional benefits (Kreider et al., 2025).

If you decide creatine is appropriate for you, I'd keep it simple.

How much should you take?

For most healthy adults, a daily dose of 3-5 g of creatine monohydrate is enough to increase muscle creatine stores over time (Kreider et al., 2025).

You may have heard about something called a loading phase, where people take around 20 g a day for five to seven days before reducing to a maintenance dose.

Whilst this does increase muscle creatine stores more quickly, it's not essential. Taking 3-5 g consistently each day achieves the same outcome; it simply takes a little longer.

For most of the women I work with, I don't think there's any real advantage to loading. Consistency is much more important.

So, who might benefit from taking creatine?

After reviewing the evidence, I think there are some women who could genuinely benefit from creatine supplementation.

For example, if you're resistance training regularly and your goal is to improve strength, increase lean muscle mass or enhance your training performance, creatine is one of the few supplements with a robust evidence base to support its use.

Equally, if you follow a vegetarian or vegan diet, you may have lower creatine stores because dietary creatine is found primarily in meat and fish. Some research suggests this may mean vegetarians and vegans experience greater improvements following supplementation, although individual responses vary (Smith-Ryan et al., 2021).

On the other hand, if you're hoping creatine will regulate your periods, improve ovulation, reduce androgen levels or improve fertility, I don't think the evidence is strong enough to recommend it specifically for those reasons.

That doesn't mean future research won't change my opinion.

It simply means I don't think it's fair to promise benefits that haven't yet been demonstrated in clinical studies.

How I approach this in clinic

One of the first questions I ask a client when we start talking about supplements is: "What are you hoping this supplement will help you achieve?"

It's a simple question, but it often changes the whole conversation.

Many women with PMOS come to clinic having spent hundreds of pounds on supplements because they felt they had to try everything. By the time we meet, they've often accumulated a cupboard full of powders, capsules and tablets, without ever feeling completely sure why they're taking them.

I don't think that's surprising.

The supplement industry is incredibly good at selling hope, particularly to women who are frustrated, exhausted and desperate to feel better. When you're told that a supplement might improve your hormones, fertility, energy or weight, it's only natural to want to believe it.

My job isn't to dismiss supplements.

Far from it.

Some supplements have a really important role in PMOS management when they're used for the right reasons and in the right person.

My job is to help you work out which ones are genuinely worth your time and money.

When it comes to creatine, I think it's one of the most promising supplements we have for supporting strength training. The evidence is strong, it's relatively inexpensive and it has an excellent safety profile.

Where I'd be more cautious is when creatine is promoted as a treatment for PMOS itself.

At the moment, the research simply hasn't caught up with those claims.

Could that change in the future? Absolutely.

Research into women's health has accelerated dramatically over the last few years, and I'm hopeful we'll continue to see more high-quality studies specifically involving women with PMOS.

Until then, I'd rather be honest about what we know, what we don't know, and where the uncertainties still exist.

I appreciate that this isn't always the most exciting message.

It's much easier to promise that one supplement will transform your hormones.

But in my experience, sustainable improvements in PMOS rarely come from finding one "magic" supplement.

They come from understanding your body, identifying what's driving your symptoms, and building a realistic plan that you can actually maintain.

Supplements can absolutely be part of that plan.

They just shouldn't have to carry all of the responsibility.

Key take-home messages

If you've skimmed the article and are looking for the headlines, here's what I'd like you to remember.

• Creatine is one of the most extensively researched sports nutrition supplements available and has consistently been shown to improve muscle strength when combined with resistance training.

• At the moment, we don't have good-quality evidence that creatine improves the core features of PMOS, including irregular periods, ovulation or fertility.

• If your goal is to improve your performance in the gym, creatine may be a sensible option.

• If your goal is to restore your menstrual cycle or improve fertility, I'd focus first on interventions with a much stronger evidence base.

• Before taking any supplement, ask yourself what problem you're hoping it will solve. The answer to that question should always guide the decision.

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I hope this article has helped you feel a little more confident navigating the conflicting advice surrounding creatine.

If you're still unsure whether creatine is appropriate for you, or you'd like personalised support with managing your PMOS, I'd love to help. Every recommendation I make in clinic is tailored to the individual sitting in front of me, because no two women with PMOS are exactly the same.

References:

Aguiar, A. J., Cruz, B., Brooks, S., et al. (2024). Creatine improves total sleep duration following resistance training days versus non-resistance training days among naturally menstruating females. Nutrients, 16.

Ellery, S. J., Walker, D. W., & Dickinson, H. (2016). Creatine for women: A review of the relationship between creatine and the reproductive cycle and female-specific benefits of creatine therapy. Amino Acids, 48(8), 1807–1817. https://doi.org/10.1007/s00726-016-2232-7

Kreider, R. B., Antonio, J., Candow, D. G., et al. (2025). International Society of Sports Nutrition (ISSN) position stand: Safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition.

Naddafha, S., Antonio, J., Kreider, R. B., & Stout, J. R. (2026). Creatine monohydrate for lean mass, strength, and bone density in postmenopausal women: A systematic review and meta-analysis. Journal of the International Society of Sports Nutrition, 23(1), 2668435. https://doi.org/10.1080/15502783.2026.2668435

Ostojic, S. M., Stea, T. H., Ellery, S. J., & Smith-Ryan, A. E. (2024). Association between dietary intake of creatine and female reproductive health: Evidence from NHANES 2017–2020. Food Science & Nutrition, 12, 4893–4898.

Santos, E. E. P., de Araújo, R. C., Candow, D. G., et al. (2021). Efficacy of creatine supplementation combined with resistance training on muscle strength and muscle mass in older females: A systematic review and meta-analysis. Nutrients, 13(11), 3757. https://doi.org/10.3390/nu13113757

Smith-Ryan, A. E., Cabre, H. E., Eckerson, J. M., & Candow, D. G. (2021). Creatine supplementation in women's health: A lifespan perspective. Nutrients, 13(3), 877. https://doi.org/10.3390/nu13030877

Smith-Ryan, A. E., DelBiondo, G. M., Brown, A. F., et al. (2025). Creatine in women's health: Bridging the gap from menstruation through pregnancy to menopause. Journal of the International Society of Sports Nutrition.