Creatine side effects in women: what does the research say?

At a dose of 3 to 10 grams per day, creatine has no clinically relevant side effects in healthy women. That is the conclusion of hundreds of randomized studies, summarized in the ISSN position stand on creatine supplementation (Kreider et al., 2017) and confirmed specifically for women by Smith-Ryan et al. (2021) in a systematic review of creatine across all female life stages, including perimenopause, menopause, and postmenopause.

That doesn't mean there aren't questions. Most concerns come from older studies in male athletes, from myths that were never scientifically confirmed, or from confusion about how creatine works. Below we explain per concern what the research actually shows.

What is creatine, and why do women have less of it?

Creatine is a substance your body produces naturally via your liver, kidneys, and pancreas. You also get it through food (meat and fish). About 95% of your body's creatine is stored in your muscles, the remaining 5% in your brain, where it serves as a rapid energy source in the ATP system of your cells.

Women have 70 to 80% lower endogenous creatine reserves than men (Smith-Ryan et al., 2021). During menopause, production drops further because oestrogen plays a role in creatine synthesis (Brosnan & Brosnan, 2007; Ellison et al., 2025). That's exactly why creatine in women during menopause is now more researched than ever.

What are the possible side effects of creatine in women?

Most women experience no side effects. When they do occur, they are usually mild and temporary: 1 to 2 kilograms of water retention in the muscles during the first week, and rare stomach issues with high doses on an empty stomach. Long-term research up to five years shows no effect on kidneys, liver, or hormones in healthy adults (Kreider et al., 2017).

A recent systematic review by Smith-Ryan et al. explicitly states that there are "no adverse effects of creatine supplementation on the gastrointestinal, renal, hepatic, or cardiovascular systems among women supplementing with creatine" (Smith-Ryan et al., 2021, section 3).

Will creatine make you gain weight?

Yes, during the first week, but it's water in your muscle, not fat. Creatine draws water into your muscle cells, not under your skin. On the scale you typically see 1 to 2 kilograms extra in the first 1 to 2 weeks. That water is intracellular (inside the muscle cell), not subcutaneous (under the skin). You don't feel bloated.

According to Antonio et al. (2021), the weight gain from creatine is "intracellular water retention, not subcutaneous fluid." Smith-Ryan et al. (2021) additionally note that this rapid weight gain "is more prevalent among males than females," because men on average have more muscle mass and therefore retain more water in the muscle.

The effect stabilizes after two to three weeks. In studies of postmenopausal women who combine creatine with strength training, creatine is actually linked to muscle preservation and a more favorable body composition over the longer term (Chilibeck et al., 2023).

Can it cause stomach issues?

Stomach issues are possible but rare with correct use. They almost exclusively occur in three situations:

• High doses (20 grams or more) taken at once
• Creatine powder that doesn't fully dissolve
• Taking it on an empty stomach without fluid

The so-called "loading phase" of 20 grams per day, split across four doses, is the main cause of reported gastrointestinal issues. That loading phase isn't necessary for women in menopause: with 10 grams per day, your creatine reaches saturation in about 2 weeks (Hultman et al., 1996). With a cold-pressed liquid shot, absorption is steadier and stomach issues are rare.

The ISSN position stand (Kreider et al., 2017) concludes that gastrointestinal complaints are "not consistently reported in controlled studies" at the recommended dosage.

Is creatine bad for the kidneys?

No. There is no evidence that creatine damages kidney function in healthy people. This is one of the most persistent myths about creatine, and it's wrong.

Creatine raises the creatinine level in your blood. Creatinine is a breakdown product of creatine that doctors use as a marker for kidney function. Higher creatinine after creatine supplementation looks like "worse kidney values," but it's not a sign of kidney damage: it's simply the result of higher creatine intake (Antonio et al., 2021).

Multiple long-term studies (up to five years) show no effect on kidney function in healthy adults. Poortmans & Francaux (1999) demonstrated that long-term creatine supplementation does not impair kidney function in healthy athletes. The ISSN concludes literally: "There is no scientific evidence that creatine supplementation is harmful to the kidneys in healthy individuals."

Exception: if you have an existing kidney condition or take medication that affects kidney function, always consult your doctor first.

Does creatine damage the liver?

No. Creatine has no demonstrated negative effect on liver function in healthy adults. Smith-Ryan et al. (2021) explicitly confirm this in their systematic review of creatine in women: no adverse effects on the hepatic system were observed.

Liver enzymes (ALT, AST) remain stable during chronic creatine use. The ISSN confirms this across studies that followed up to five years of supplementation. As with the kidneys, the exception applies for existing liver conditions: consult your doctor.

Does creatine cause muscle cramps?

No, the opposite. Research shows creatine users report fewer muscle cramps, not more.

This is a common concern that gets reversed in the science. The ISSN position stand cites research in which creatine users reported "less incidence of cramping, heat illness/dehydration, muscle tightness, muscle strains/pulls, and total injuries." The reason: creatine supports water balance and energy delivery at the cellular level, which works against cramps rather than for them.

If you do get a cramp, it's usually not a result of creatine itself but of insufficient fluid intake or an electrolyte deficit. A shot with both creatine and electrolytes (sodium, potassium, magnesium) addresses both at once.

Does creatine affect female hormones?

No. Creatine works at the cellular energy level (the ATP system), not on the hormonal system. There is no demonstrated effect on oestrogen, progesterone, or other female hormones.

There was once one study (van der Merwe et al., 2009) that suggested a rise in DHT (dihydrotestosterone) in male rugby players after three weeks of high-dose creatine. That finding:

• Has never been replicated in follow-up research
• Concerned only men, not women
• The measured DHT values stayed within the normal physiological range

Antonio et al. (2021) discuss this specifically as one of the biggest misconceptions about creatine. A recent randomized controlled trial from 2025 found no effect on DHT, testosterone, or any hair-related outcome after 12 weeks of creatine supplementation.

Does creatine cause hair loss?

No. There is no research that shows a causal link between creatine and hair loss. This concern is directly derived from the DHT study above, but:

• That study measured DHT, not hair loss
• The rise stayed within the normal range
• There has never been a replication or actual hair loss demonstrated

The 2025 RCT confirms after 12 weeks of creatine supplementation in both men and women: no change in DHT, no hair loss, no hormonal shift. For women in menopause, where hair thinning is a common complaint, there is no scientific evidence that creatine worsens this.

Does creatine affect sleep or mood?

Research suggests positive effects on sleep and mood, not negative ones. A randomized trial from 2025 in perimenopausal and postmenopausal women found that eight weeks of creatine supplementation improved sleep quality and reduced the severity of mood swings.

Smith-Ryan et al. (2021) report in their systematic review that "8 weeks of creatine supplementation reduced depressive symptoms in adolescent and adult women," likely by restoring the energy balance in the brain. There are no studies that link sleep disturbance or mood deterioration to creatine at the recommended dosage.

Are there side effects specific to women in menopause?

No. There are no side effects that occur exclusively in women during menopause. The Smith-Ryan review from 2021, which covered creatine across the full female life cycle, found no increased risk of side effects in perimenopausal, menopausal, or postmenopausal women compared with younger women or men.

On the contrary: specifically during menopause, creatine is linked in randomized studies to muscle and bone mass preservation when combined with strength training. Chilibeck et al. (2023) conducted a two-year RCT in postmenopausal women and demonstrated that creatine plus resistance training maintained femoral neck bone mineral density better than training alone.

When to avoid creatine

• Existing kidney or liver conditions: always consult your doctor
• Medication that affects kidney function (certain blood pressure medications, diuretics): consult your doctor
• During pregnancy or breastfeeding: there is insufficient long-term research
• Existing medical condition: discuss with your GP or specialist first

Creatine monohydrate is a dietary supplement, not medicine. But your doctor knows your personal situation and current medications.

How to minimize side effects

Practical tips aligned with the research:

• Start with 10 grams per day instead of a loading phase. Faster saturation than 3 to 5 grams, without the stomach issues of 20 grams per day.
• Take it with food or fluid, not on an empty stomach.
• Choose a liquid form or cold-pressed shot if you're sensitive to stomach issues from powder.
• Drink enough water during the day (2 to 3 liters).
• Combine with strength training to maximize the effects on muscle and bone mass (Chilibeck et al., 2023).
• Give it time: most effects (and any side effects) stabilize after 2 to 3 weeks.

Summary: what does the science say?

Concern	What the research shows	Source
Weight gain	1 to 2 kg water in the muscle, not fat. Stabilizes after 2 weeks.	Antonio 2021, Smith-Ryan 2021
Stomach issues	Rare with correct use. Avoid 20g loading phase.	ISSN 2017
Kidneys	No damage in healthy people, studied up to 5 years.	Poortmans 1999, ISSN 2017
Liver	No effect on liver enzymes or hepatic function.	Smith-Ryan 2021, ISSN 2017
Muscle cramps	Less frequent in creatine users, not more.	ISSN 2017
Hormones	No effect on oestrogen, progesterone, or female hormones.	Smith-Ryan 2021
Hair loss	No evidence, refuted by 2025 RCT.	2025 RCT
Sleep and mood	Rather positive effects than negative.	2025 RCT, Smith-Ryan 2021
Specific in menopause	No increased risk. Actually beneficial for muscle/bone with training.	Chilibeck 2023

Read more

• Creatine benefits for women: what the research says
• Creatine & Menopause: the complete guide
• Best creatine for women in menopause: the guide
• Best supplements for women in menopause

Sources

• Kreider, R.B. et al. (2017). International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation. Journal of the International Society of Sports Nutrition, 14(18).
• Smith-Ryan, A.E. et al. (2021). Creatine Supplementation in Women's Health: A Lifespan Perspective. Nutrients, 13(3), 877.
• Antonio, J. et al. (2021). Common questions and misconceptions about creatine supplementation. Journal of the International Society of Sports Nutrition, 18(1), 13.
• Chilibeck, P.D. et al. (2023). A 2-year randomized controlled trial on creatine supplementation during exercise for postmenopausal bone health. Medicine & Science in Sports & Exercise, 55(10), 1750-1760.
• Poortmans, J.R. & Francaux, M. (1999). Long-term oral creatine supplementation does not impair renal function in healthy athletes. Medicine and Science in Sports and Exercise, 31(8), 1108-1110.
• Brosnan, J.T. & Brosnan, M.E. (2007). Creatine: endogenous metabolite, dietary, and therapeutic supplement. Annual Review of Nutrition, 27, 241-261.
• Ellison, C. 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.
• van der Merwe, J. et al. (2009). Three weeks of creatine monohydrate supplementation affects DHT to testosterone ratio in college-aged rugby players. Clinical Journal of Sport Medicine, 19(5), 399-404.
• Antonio, J. et al. (2025). Examining the effects of 12 weeks of low and high dose creatine supplementation on biomarkers of hair health and testosterone in resistance-trained individuals. Journal of the International Society of Sports Nutrition.
• Impact of creatine supplementation on menopausal women's body composition, cognition, oestrogen, strength, and sleep (2025).
• Hultman, E. et al. (1996). Muscle creatine loading in men. Journal of Applied Physiology, 81(1), 232-237.
• Dr. Stacy Sims: Why Active Women Need Creatine