How your menstrual cycle impacts creatine supplementation.
January 21, 2023

Did you know that creatine supplementation can have a different impact on your fluid distribution depending on your menstrual cycle phase?
Creatine is a popular supplement that many athletes use, however, studies show that only 20% of females include this supplement in their regimen because they fear the weight gain that is often associated with the creatine loading phase.
This less common usage in females can be detrimental because creatine supplementation currently only demonstrates positive benefits for the body and mind. No adverse side effects have been reported to our knowledge. Not only does this supplement help to delay fatigue during repeated high intensity exercise, it has also been linked with improved cognition and bone health, especially in female populations.
Though research has shown that individuals tend to show an increase in body weight during creatine loading phases, it’s important to note that much of the research concerning creatine has been conducted on men or mixed sexes in the studies. Thus, there are rarely any trials conducted exclusively on females to demonstrate the same result.
This should raise some questions because we do know that the fluctuating hormones that play a huge role in the menstrual cycle, including estrogen and progesterone, can greatly influence fluid distribution. Past research has shown that during the high hormone luteal phase, there is a greater fluid shift to the extracellular space, which may impair exercise performance.
In a study published just about a month ago in December 2022, scientists decided to explore whether females would demonstrate a similar increase in body weight due to fluid retention from creatine supplementation.
To do so, they recruited 30 moderately active females who were either naturally menstruating and on a regular menstrual cycle or using hormonal contraceptives. They used a double blind, placebo-controlled design that included a menstrual phase crossover. Researchers measured several factors to consider fluid distribution: body mass, total body water, extracellular fluid, and intracellular fluid.
They ultimately found that creatine loading only demonstrated significant increases in the females’ total body water, extracellular fluid, and intracellular fluid during the luteal phase. They also found no significant difference between the naturally menstruating group and the group using hormonal contraceptives.
What does this mean?
Well, it appears that there was no significant increase in body mass during creatine supplementation, so the fear of “gaining weight” from the supplement might just be a myth for females.
This study not only demonstrates that creatine supplementation may impact males and females differently, but it also provides further evidence that more research needs to be conducted on females to learn more about how the menstrual cycle and fluctuating female hormones may influence supplementation recommendations, nutrition recommendations, and more.
To learn more about whether creatine supplementation is right for you and how you can properly start creatine loading, click here book a FREE 15 minute call with one of our practitioners today!
You can also learn more about creatine and other supplements that have been proven to improve performance in our mini-course here.
References:
Moore, S. R., Gordon, A. N., Cabre, H. E., Hackney, A. C., & Smith-Ryan, A. E. (2023). A Randomized Controlled Trial of Changes in Fluid Distribution across Menstrual Phases with Creatine Supplementation. Nutrients, 15(2), 429. https://doi.org/10.3390/nu15020429