Despite being among the most extensively studied nutritional supplements in existence (over 500 peer-reviewed studies, consistent safety data across multiple populations, and a well-characterised mechanism of action), creatine is still widely associated only with male bodybuilders, and its evidence base for perimenopausal women remains largely unknown outside specialist sports medicine circles.

What Creatine Does

Creatine is a compound synthesised in the body from the amino acids arginine, glycine, and methionine, primarily in the liver and kidneys. It is also obtained from meat and fish. Around 95% of total body creatine is stored in skeletal muscle as phosphocreatine, with the remaining 5% in the brain and other tissues.

Phosphocreatine's primary role is as a rapid energy buffer. During high-intensity muscular effort, the body regenerates ATP (adenosine triphosphate, the cell's energy currency) from ADP using phosphocreatine. This system provides energy for the first 8 to 10 seconds of maximal effort and supports repeated bouts of high-intensity work by accelerating ATP regeneration between efforts.[1]

Beyond acute energy provision, creatine supports skeletal muscle protein synthesis, may reduce markers of muscle damage and inflammation after exercise, influences brain energy metabolism, and appears to interact with bone metabolism through effects on osteoblast function.[2]

Why Perimenopause Matters Here

Perimenopausal women face concurrent declines in muscle mass, bone density, and cognitive function, all areas with evidence for creatine benefit. They also tend to have lower creatine stores than men at baseline (smaller muscle mass means lower total storage capacity), lower dietary creatine intake (women eat less meat on average), and reduced synthesis efficiency with age.[3]

Several mechanisms make perimenopause a relevant context for supplementation:

Declining estrogen reduces muscle anabolic signalling. Estrogen and testosterone both support muscle protein synthesis. As both decline in perimenopause, the anabolic environment for muscle becomes less favourable. Creatine enhances mTOR signalling pathways for muscle protein synthesis and can partly offset declining hormonal anabolic drive.[4]

Brain energy demand during hormonal fluctuation. Estrogen supports neuronal energy metabolism, and its decline may reduce the efficiency of cerebral energy utilisation. Creatine, stored as phosphocreatine in the brain as well as muscle, supports neuronal ATP regeneration and may buffer energy shortfalls that contribute to brain fog and cognitive fatigue.[5]

Muscle: The Evidence

A systematic review and meta-analysis by Lanhers et al. examining creatine supplementation in women found improvements in upper limb muscle strength compared to placebo, with effects present across age groups including postmenopausal women.[6]

A meta-analysis by Chilibeck et al. (2017) of creatine supplementation during resistance training in older adults found that creatine groups gained significantly more lean mass and showed greater strength gains than resistance training plus placebo groups.[7] The interaction between creatine and resistance training is more pronounced than either alone: creatine amplifies the muscle response to exercise rather than replacing the need for it.

This synergy is mechanistically coherent. Creatine enhances the ability to perform more total work in a training session (more reps, shorter rest to fatigue), and this greater stimulus, combined with creatine's anabolic signalling effects, produces more muscle adaptation.

Bone: The Evidence

Candow et al. (2015) found that creatine supplementation attenuated bone mineral density loss at the hip compared to placebo in older adults doing resistance training. This has a proposed mechanism: creatine may support osteoblast (bone-building cell) energy production, since osteoblasts are energetically demanding cells.[8]

Bone effects from creatine are smaller than from pharmacological interventions for osteoporosis. Creatine is not a substitute for calcium, vitamin D, or bisphosphonates where indicated. As an additive effect on top of resistance training, itself one of the most evidence-based lifestyle interventions for bone, it is clinically relevant.

Brain and Cognitive Function

This is the most rapidly developing area of creatine research. A meta-analysis of randomised trials by Avgerinos et al. published in Experimental Gerontology found that creatine supplementation produced improvements in memory performance, with effects most pronounced in older adults and vegetarians (who have lower baseline creatine from dietary sources).[9]

A review examining creatine and brain health in women found evidence for improved working memory and reduced mental fatigue under sleep deprivation, directly relevant for perimenopausal women with vasomotor-disrupted sleep.[10]

The mechanism: the brain stores phosphocreatine and uses it to buffer energy supply during periods of high demand or reduced oxygen. Cognitive tasks requiring sustained attention and working memory deplete local brain phosphocreatine. Supplementation increases the available pool, reducing the rate of depletion during demanding tasks.

For women experiencing brain fog and cognitive fatigue in perimenopause, the mechanism is plausible. Longer trials in perimenopausal women specifically are underway; the current evidence base is RCT-level for older adults but largely observational for perimenopausal women.

Mood

Smaller studies have found antidepressant effects of creatine supplementation, with a proposed mechanism involving brain energy metabolism and the monoamine neurotransmitter system: creatine may support the ATP-dependent steps in monoamine synthesis and reuptake that are disrupted in depression.[11] A pilot randomised trial by Kondo et al. found that creatine augmented the effects of antidepressant medication in adolescent girls (ages 13–21) with SSRI-resistant major depressive disorder; the study population was not adult women. This is preliminary evidence and should not be interpreted as a treatment for clinical depression, but it adds to the biological plausibility of creatine affecting brain function beyond cognition.

Practical Guidance

Dose. The evidence-based dose for muscle and cognitive outcomes is 3 to 5 g of creatine monohydrate per day. Loading phases (20 g per day for 5 to 7 days) saturate stores more rapidly, but a maintenance dose without loading reaches the same endpoint within 3 to 4 weeks.[12]

Form. Creatine monohydrate is the only form with a substantial evidence base. Marketed alternatives such as creatine HCl, buffered creatine, and creatine ethyl ester lack equivalent research support and are typically more expensive. There is no evidence they are superior.

Timing and food uptake. Creatine taken close to exercise sessions (before or after) may be slightly more effective for muscle outcomes, though the difference is small. Consistency of daily dosing matters more than precise timing.[13] Creatine uptake into muscle is enhanced by insulin, so taking it with a meal containing carbohydrate or protein improves uptake compared to taking it fasted.[14]

Tolerability. Creatine draws water into muscle cells; adequate hydration (30 to 35 ml per kg body weight per day) supports this and prevents the mild gastrointestinal discomfort some people experience at higher doses. Creatine monohydrate has been studied in clinical populations for over three decades with no serious adverse effects at standard doses in healthy adults. The only consistent side effect is mild gastrointestinal discomfort at doses above 10 g in some individuals, which is avoided with standard 3 to 5 g daily doses. Concerns about kidney damage from creatine are not supported by clinical evidence in people with normal kidney function.[15]

When to discuss with your GP. If you are currently taking HRT, SSRIs, or bisphosphonates (all common in this age group), it is worth flagging creatine supplementation at your next appointment, as your GP may want to note it in the context of ongoing monitoring. Women with chronic kidney disease should not take creatine without medical review, since impaired metabolism of creatinine (the breakdown product of creatine) could affect monitoring.

References

[1] Greenhaff, P. L., Bodin, K., Soderlund, K., Hultman, E. (1994). Effect of oral creatine supplementation on skeletal muscle phosphocreatine resynthesis. American Journal of Physiology, 266(5 Pt 1), E725–E730. https://doi.org/10.1152/ajpendo.1994.266.5.E725

[2] Kreider, R. B., Kalman, D. S., Antonio, J., et al. (2017). International Society of Sports Nutrition position stand: Safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition, 14, 18. https://doi.org/10.1186/s12970-017-0173-z

[3] Smith, C. A. M., Salmon, S., Clark, T., Bruce, C., Burd, N. A., Moore, D. R. (2022). Creatine supplementation in women: A review of creatine's effect on lean tissue mass, strength, and performance in females. Nutrients, 14(7), 1434. https://doi.org/10.3390/nu14071434

[4] Deldicque, L., Theisen, D., Francaux, M. (2005). Regulation of mTOR by amino acids and resistance exercise in skeletal muscle. European Journal of Applied Physiology, 94(1–2), 1–10. https://doi.org/10.1007/s00421-004-1255-6

[5] Dolan, E., Gualano, B., Rawson, E. S. (2019). Beyond muscle: The effects of creatine supplementation on brain creatine, cognitive processing, and traumatic brain injury. European Journal of Sport Science, 19(1), 1–14. https://doi.org/10.1080/17461391.2018.1500644

[6] Lanhers, C., Pereira, B., Naughton, G., Trousselard, M., Lesage, F. X., Dutheil, F. (2017). Creatine supplementation and upper limb strength performance: A systematic review and meta-analysis. Sports Medicine, 47(1), 163–173. https://doi.org/10.1007/s40279-016-0571-4

[7] Chilibeck, P. D., Kaviani, M., Candow, D. G., Zello, G. A. (2017). Effect of creatine supplementation during resistance training on lean tissue mass and muscular strength in older adults: A meta-analysis. Open Access Journal of Sports Medicine, 8, 213–226. https://doi.org/10.2147/OAJSM.S123529

[8] Candow, D. G., Vogt, E., Johannsmeyer, S., Forbes, S. C., Farthing, J. P. (2015). Strategic creatine supplementation and resistance training in healthy older adults. Applied Physiology, Nutrition, and Metabolism, 40(7), 689–694. https://doi.org/10.1139/apnm-2014-0498

[9] Avgerinos, K. I., Spyrou, N., Bougioukas, K. I., Kapogiannis, D. (2018). Effects of creatine supplementation on cognitive function of healthy individuals: A systematic review of randomized controlled trials. Experimental Gerontology, 108, 166–173. https://doi.org/10.1016/j.exger.2018.04.013

[10] Rawson, E. S., Venezia, A. C. (2011). Use of creatine in the elderly and evidence for effects on cognitive function in young and old. Amino Acids, 40(5), 1349–1362. https://doi.org/10.1007/s00726-011-0855-9

[11] Kondo, D. G., Sung, Y. H., Hellem, T. L., et al. (2011). Open-label adjunctive creatine for female adolescents with SSRI-resistant major depressive disorder: A 31-phosphorus magnetic resonance spectroscopy study. Journal of Affective Disorders, 135(1–3), 354–361. https://doi.org/10.1016/j.jad.2011.06.004

[12] Hultman, E., Soderlund, K., Timmons, J. A., Cederblad, G., Greenhaff, P. L. (1996). Muscle creatine loading in men. Journal of Applied Physiology, 81(1), 232–237. https://doi.org/10.1152/jappl.1996.81.1.232

[13] Antonio, J., Ciccone, V. (2013). The effects of pre versus post workout supplementation of creatine monohydrate on body composition and strength. Journal of the International Society of Sports Nutrition, 10, 36. https://doi.org/10.1186/1550-2783-10-36

[14] Green, A. L., Hultman, E., Macdonald, I. A., Sewell, D. A., Greenhaff, P. L. (1996). Carbohydrate ingestion augments skeletal muscle creatine accumulation during creatine supplementation in humans. American Journal of Physiology, 271(5 Pt 1), E821–E826. https://doi.org/10.1152/ajpendo.1996.271.5.E821

[15] Gualano, B., Roschel, H., Lancha, A. H., Brightbill, C. E., Rawson, E. S. (2012). In sickness and in health: The widespread application of creatine supplementation. Amino Acids, 43(2), 519–529. https://doi.org/10.1007/s00726-011-1132-7