Creatine has officially gone from “gym bro supplement” to one of the most widely researched and beneficial supplements for women’s health.

And, it’s about time.

For years, creatine was mostly associated with bodybuilders and athletes trying to gain muscle. Remember those massive creatine containers you’d see stacked behind the check-in desk at your gym in the 90’s? Or is that just me? 😂

Over the last few years, researchers and practitioners have started paying much closer attention to how creatine supports women specifically — including our hormones, metabolism, cognition, mood, energy, and even reproductive health.

In fact, a few years ago when I had Stacy Sims on the podcast and asked which supplement she’d recommend over almost any other for women, she immediately said creatine.

That definitely got my attention.

But there’s also a newer conversation emerging around creatine and endometriosis that deserves a much more nuanced discussion than what’s currently happening online.

Because while creatine appears to be incredibly beneficial for many women, some of the latest research suggests there may be reasons for caution in women with endometriosis.

So let’s unpack all of it.

What Is Creatine?

Creatine is a naturally occurring compound made from amino acids that’s stored primarily in your muscles and brain.

Your body produces some creatine on its own, and you also get it from foods like:

• red meat
• fish
• eggs

Its main job is helping your body produce ATP (adenosine triphosphate), which is essentially the body’s cellular energy currency.

In simple terms: creatine helps your cells make and use energy more efficiently.

And while we often think about muscles needing energy, so do:

• your brain
• your ovaries
• your nervous system
• your heart
• your metabolism

Which is exactly why creatine has become such an interesting topic in women’s health.

Why Creatine Matters for Women’s Hormonal Health

1. Your ovaries rely heavily on cellular energy

Ovulation is an extremely energy-intensive process.

Your ovarian mitochondria need massive amounts of ATP to support:

• egg maturation
• ovulation
• sex hormone production (estrogen, progesterone and testosterone)
• overall reproductive function

Creatine helps support mitochondrial energy production, which may be one reason so many women notice improvements in ovulation and sex hormone production when taking it regularly.

2. It may support blood sugar regulation

Creatine appears to help improve how glucose moves into cells, which can support insulin sensitivity and more stable blood sugar.

For women, this can translate into:

• fewer cravings
• more stable energy
• less PMS-related hunger
• fewer blood sugar crashes
• improved mood stability

And since blood sugar dysregulation can impact cortisol, ovulation, and sex hormone production, this matters more than most people realize.

3. It supports brain function and mood

One of the most fascinating areas of creatine research is its impact on the brain.

Studies suggest creatine may help support:

• cognitive function
• memory
• mental clarity
• mood
• energy levels

And because women experience fluctuating hormonal shifts across the menstrual cycle, pregnancy, postpartum, and perimenopause, having additional support for brain energy metabolism can be incredibly valuable.

4. It may help during the luteal phase

Many women feel more fatigued, depleted, or emotionally vulnerable during the second half of their cycle.

That’s not “all in your head.”

The luteal phase increases metabolic demands, and if your cells are already struggling to produce adequate energy, you’ll often feel it through:

• fatigue
• mood changes
• cravings
• poor recovery
• brain fog

Creatine may help buffer some of that increased energetic demand.

5. It supports muscle and metabolic health

This is one of the reasons creatine is becoming especially popular in perimenopause and menopause conversations.

As estrogen declines, women become more vulnerable to:

• muscle loss
• insulin resistance
• reduced recovery
• decreased metabolic flexibility

Creatine, especially when combined with strength training and adequate protein intake, may help support lean muscle mass, strength, and metabolic health as women age.

So Why Is Everyone Suddenly Talking About Creatine & Endometriosis?

Here’s where things get really interesting.

Over the last couple of years, emerging research has raised important questions about the relationship between creatine metabolism and endometriosis.

And to be clear, this research is still early, mostly mechanistic, and far from conclusive.

But I do think it’s important that women with endometriosis at least understand what researchers are seeing so they can make informed decisions.

Because this isn’t a black-and-white conversation.

What the Research Currently Shows

1. Endometriosis tissue appears to produce excess creatine

Researchers have found that endometriosis lesions and surrounding peritoneal fluid appear to generate significantly higher levels of endogenous creatine production compared to healthy tissue. Some researchers are even exploring creatine metabolism as a possible diagnostic biomarker for endometriosis.

Importantly, this refers to creatine the body is making internally – not necessarily supplemental creatine. We still do not know whether dietary creatine supplementation directly influences this process in humans.

2. Creatine may help endometriosis cells resist cell death

One newer study found that creatine may suppress a process called ferroptosis in endometriosis cells. Ferroptosis is a type of iron-dependent programmed cell death that may help the body clear abnormal tissue.

Researchers found that creatine appeared to help endometriosis cells survive when they otherwise may have died off.

Again, this was mechanistic research – not human clinical data – but it raises important questions.

3. Mouse studies showed increased lesion growth

In mouse models, supplemental creatine appeared to increase:

• lesion size
• lesion weight
• lesion number

Researchers proposed that creatine may influence immune signaling and macrophage behavior within the endometriosis environment.

But mice are not humans, and animal data does not automatically translate into clinical outcomes for women.

Still, it’s worth paying attention to.

4. Human studies are still extremely limited

At this point, we do not have human clinical trials evaluating whether creatine supplementation worsens:

• endometriosis symptoms
• pain
• fertility outcomes
• lesion progression

However, one recent study did find that higher serum creatinine levels (a breakdown product of creatine metabolism) were associated with increased endometriosis risk.

Again, this reflects association – not causation – and it still doesn’t prove that supplemental creatine is harmful in women with endometriosis.

But it does suggest there may be a meaningful connection between creatine metabolism and the disease process itself.

So Should Women With Endometriosis Avoid Creatine?

At this stage, I don’t think we have enough evidence to make sweeping recommendations either way. And I think this is where nuance matters.

Because on one hand, creatine has incredibly well-established benefits for:

• brain health
• energy
• muscle health
• cognition
• mood
• blood sugar regulation
• metabolic resilience

But on the other hand, the emerging endometriosis research is interesting enough that I personally think women with endometriosis should proceed thoughtfully and pay close attention to how they respond.

My general thoughts would be:

• work with a knowledgeable practitioner
• start with lower doses
• monitor symptoms carefully
• pay attention to pain, bloating, inflammation, and flare patterns
• reassess regularly

And perhaps most importantly, don’t ignore your own lived experience.

Some women with endometriosis report feeling significantly better on creatine. Others feel like it worsens symptoms or contributes to flares.

Right now, we genuinely do not know why.

My Take

I still believe creatine is one of the most promising and beneficial supplements for many women.

The research supporting its role in cognitive health, muscle strength and recovery, metabolism, energy production and aging is very impressive.

But I also believe women deserve nuanced conversations versus the oversimplified, mostly black-and-white wellness trends we tend to see too much of online!

Honest, evolving discussions about what the research is showing and how to make informed decisions for your own body is where its at.

And this is one of those conversations.

Potential Side Effects of Creatine (And What’s Actually Normal)

While creatine is generally considered very safe and well-researched, some women do notice temporary side effects when they first start taking it.

The most common ones are:

• bloating
• water retention
• digestive discomfort
• feeling “puffy”
• mild weight gain on the scale

And honestly, this is often the reason women stop taking creatine before they ever experience the benefits.

But here’s what’s important to understand:

Creatine naturally pulls water into your muscles

This is actually part of how creatine works.

Creatine increases intracellular water retention, meaning it helps draw water into muscle cells where it supports energy production and muscle function.

This is not necessarily the same thing as generalized inflammation or hormonal bloating.

That said, some women are definitely more sensitive to fluid shifts than others, especially women who:

• already struggle with PMS-related bloating
• have high estrogen symptoms
• have gut issues
• are very sensitive to supplements
• have endometriosis
• start with doses that are too high

Starting low is often the best approach

Many creatine protocols online recommend “loading phases” of 20g daily for several days.

Personally, I don’t think most women need to do this.

In fact, I often think slower is better.

Starting with:

• 1–2g daily
• then gradually increasing to 3–5g daily

can help reduce the likelihood of bloating or digestive discomfort.

In many cases, the bloating improves over time

For a lot of women, the initial water retention settles after a couple of weeks as the body adjusts.

But not always.

And this is where I think paying attention to your individual response matters.

If you consistently feel:

• more inflamed
• significantly bloated
• uncomfortable
• puffy
• or like your symptoms are worsening

that’s important information.

Especially if you have endometriosis or underlying inflammatory issues.

How to Use Creatine

If you decide to experiment with creatine, here are a few general guidelines:

• Creatine monohydrate is the most studied form. Consider using a high quality creatine monohydrate.
• Most women do well with 3–5g daily
• Consistency matters more than loading phases
• Staying hydrated is important
• Pairing creatine with adequate protein and strength training tends to work best

Personally, I like and use Thorne Research Creatine because it’s a highly researched, micronized creatine monohydrate powder that mixes easily and is tasteless. There are, however, lots of other high quality brands available, so make sure to do your research and find one that is third-party tested.

And as always, if you have endometriosis or any complex health condition, I strongly encourage discussing supplementation with your healthcare provider before starting.

References

• “Creatine Promotes Endometriosis by Inducing Ferroptosis Resistance via Suppression of PrP” – PubMed Study
• “Creatine promotes endometriosis progression by inducing M2 polarization of peritoneal macrophages” – PubMed Study
• “Serum creatinine as a risk factor for endometriosis” – PubMed Study