Relatively few sports supplements have an abundance of nearly undeniable research supporting their effectiveness. Many fall into the vague category of “probably works for most people most of the time.” Creatine is one of the rare standouts.
The International Society of Sports Nutrition (ISSN) concluded creatine is the most effective performance supplement available for supporting high intensity exercise and muscle mass. (1)(2) The American College of Sports Medicine (ACSM) has published a similar stance. (3)
Despite favorable position stances in the scientific community, decades of research, and more than 500 peer-reviewed publications, creatine supplementation is still misunderstood. (4) This misunderstanding is largely limited to the uninitiated public, which is a shame because a wide variety of people (even non-lifters) might benefit from creatine supplementation. (5)
If you are unfamiliar with creatine, or if you could use a science-based refresher, it’s best to start with the basics. No, creatine is not a steroid. And, no, it won’t melt your kidneys. In fact, creatine monohydrate, the most common form of supplemental creatine, is generally recognized as safe (G.R.A.S) — an official designation which can only be applied to foods and products which have undergone stringent examination and critical review. (1)(6)(7)
Creatine’s potential benefits extend beyond athletic competition and the gym. Check out the benefits, potential side effects, and common dosing protocols below.
Editor’s Note: The content on Breaking Muscle is meant to be informative in nature, but it should not be taken as medical advice. When starting a new training regimen, diet plan, and/or supplement protocol, it is always a good idea to consult with a trusted medical professional. We are not a medical resource. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. They are not substitutes for individualized consulting with a qualified medical professional.
Creatine supplementation has been studied among individuals young and old, athletes and non-athletes, healthy and injured. Creatine exerts effects on the musculoskeletal system, nervous system (e.g. brain), and endocrine system (e.g. hormones).
Some of these effects are immediate — better lifts, higher work capacity, and cognitive benefits. Others take a bit longer to register — increased muscularity, better recovery between workouts, and potentially increased performance during injury rehabilitation. Find a summary of some of the most exciting benefits of creatine below.
In training studies, creatine supplementation is consistently shown to improve strength. (1) For example, in just six weeks, lifters taking creatine showed greater improvements in chest press and leg press strength compared to those taking a placebo. (8) Strength improvements have been documented with creatine supplementation across the lifespan — from young to very old. (5)(9)
Without getting too deep into biochemistry, creatine supports energy production via the phosphagen system — this is the system that supplies energy for brief high-intensity efforts such as short sprints, jumps, and heavy, low repetition lifts. Creatine is found in foods like meat and seafood, and our bodies are able to synthesize it from other amino acids. However, supplemental creatine appears to be necessary to “top off” or saturate our muscles with creatine.
Recharged Repeated Efforts
Anyone who has ever sprinted 50-meter repeats or hit high-effort cluster sets knows the phosphagen system takes time to replenish before you’re ready to go again. Creatine supplementation may reduce the time needed to restore energy for the next high intensity set.
The mass action from having extra creatine available drives more rapid re-synthesis of phosphocreatine, the active form of creatine used for quick energy. In addition to benefiting training performance, this potential effect of creatine supplementation may have performance implications in sports like basketball, hockey, football, and volleyball. (1)
More Muscle Mass
Because creatine promotes the ability to move more weight and higher performance across repeated efforts, it should come as no surprise that it ultimately supports gains in muscle mass and improvement in body composition.
Once again, this effect is seen among individuals ranging from young to very old. (1)(9) Bodybuilders, athletes, folks who want to look better at the beach, aging adults wishing to remain independent, and more may benefit from the muscle-building effects of creatine.
Increased Training Tolerance
Creatine supplementation is known to help improve recovery from a single session of hard exercise. (10)(11) Perhaps surprisingly, some studies show increases in exercise-induced muscle damage following consistent use of creatine. (10)
Researchers attribute this to the other beneficial effects of creatine supplementation — More strength, more muscle, and more high-intensity sets and reps following consistent supplementation intuitively lead to the potential for more muscle damage during workouts. (10)
Altogether, creatine appears to be a great tool for recovery from isolated bouts of exercise, particularly the sort of workouts that involve high-load eccentric (“lengthening”) muscle contractions or novel exercises.
Are you a lifter training for a local 5k, half marathon, or triathlon? Or, maybe you’re a trail runner or cyclist dedicated to building some extra strength? Athletes who train for aerobic- and strength performance in the same workouts may struggle to maintain their strength as aerobic training ramps up. Creatine might help. A study on strength-trained men taking either creatine monohydrate or placebo were put through running workouts prior to leg resistance training.
Only individuals taking creatine were able to maintain their leg press strength-endurance (i.e. repetitions to failure at 80%), while the men taking the placebo showed reduced leg press performance. (12) Concurrent training for aerobic and strength- or physique goals is never going to be easy, but supplemental creatine might play a supporting role.
Ramped Up Recovery Following Injury
Injured individuals tend to drop or dial back their supplement regimes, often planning to resume once healthy again. But there’s a strong case for creatine supplementation during times of injury. (13) Due to the aforementioned antioxidant-like effect of creatine, its well-established benefits to muscle mass and strength, and other potential effects, supplemental creatine may have promise for those rehabilitating injuries.
Immediately following injury, affected body parts may be rested or even immobilized. Studies assessing the effects of creatine supplementation among individuals experiencing immobilization show protective effects on muscle protein composition and accelerated recovery of strength and size during their return to exercise. (14)(15)
It should be noted, current evidence for creatine during post-surgical rehabilitation is currently not as strong as the evidence for use during true immobilization. (16) While creatine may not be a panacea, banged up athletes, wrecked weekend warriors, and the clinicians who manage their care should consider the potential role of creatine supplementation post-injury.
Free Radicals Scavenged and Scrubbed Out
Free radicals are highly reactive chemicals related to cell damage, aging, and number of disease processes. For better or worse, free radicals are produced during normal metabolism. Fortunately, creatine acts to scavenge and scrub out a type of free radical called reactive oxygen species (ROS). (1)
While more research is needed to substantiate the potential role of creatine in systemic health, cellular aging, and disease, the antioxidant-like role of creatine points to applications for general health and wellness.
Boosted Brain Power
Just as creatine supplementation increases creatine concentrations in muscle, it also increases levels in brain tissue. (5) Just as muscle runs on creatine-based substrate, so to does the brain. Research is mounting in support of a creatine’s potential role as a nootropic, or brain-booster.
Vegetarians on a six-week “maintenance dose” of creatine monohydrate (five grams per day) performed better on tests of working memory and intelligence than they did on a placebo supplement. (17)
Now, one could argue that since a common source of dietary creatine is meat, the vegetarian subjects were simply correcting a deficiency, but the demonstrated link between creatine and brain power remains relevant.
In two separate studies on sleep-deprived youngsters and rested elderly individuals, McMorris and colleagues reported positive effects of creatine supplementation on working memory and long-term recall. (18)(19) In both studies, “loading doses” of creatine monohydrate were used — 20 grams per day for seven and 14 days, respectively.
Since update of creatine in brain tissue may be less efficient than skeletal muscle, more research needed to establish dosing parameters that best elicit creatine’s cognitive effects.
Numerous studies have failed to show clinically-relevant side effects of creatine monohydrate supplementation across a wide variety of populations (athletes, children, adults, older adults) and using a wide range of doses (three to 30 grams per day). (1)(20)
Aside from the benefits discussed above, one potentially relevant side effect is increased body mass, which can occur early due to increased water content in the body.
Early Water Retention
The most commonly reported side effect of creatine is water retention. Studies have reported early increases in body mass during the initial days of creatine supplementation too rapid to be attributed to muscle gain. (4) Instead, these increases appear to be primarily driven by increases in intracellular water, or water found within the cells which plays a key role in cellular health and performance. (21)
In the first three days or so of creatine supplementation (loading dose), it is common to see gains of two to four pounds of water weight. (21) Fortunately, there is probably no reason to worry about medium- or long-term bloating when supplementing with creatine. Intracellular water levels are shown to normalize after weeks to months of use. (4)
Creatine monohydrate mixes reasonably well with liquid, particularly if you purchase “micronized” powder, which is milled or sifted to smaller particles. Creatine supplementation need not be complicated — standard practices and considerations are provided below.
The most common supplementation protocols involve three to five grams creatine monohydrate per day, or 0.1 gram per kilogram bodyweight. (4)(22) Gradually, creatine levels in muscle cells will increase above baseline and individuals will likely begin to realize the benefits discussed above.
This dosing protocol is referred to as a “maintenance dose,” because once muscle tissues reach creatine saturation, ongoing supplementation at this dose is likely to maintain high or maximum levels. Although about one-third of studies on creatine supplementation involve only a maintenance dose, just as many incorporate a loading dose to “jumpstart” the benefits.
Consider a Loading Dose
With typical creatine doses (i.e. three to five grams per day), it may take weeks before muscles are saturated. Therefore, a “loading dose” is often recommended to accelerate this process. (1)(22) The most common creatine monohydrate loading protocol involves 20 grams per day for five to seven days. (1)(22)
The daily 20-gram loading dose is typically divided into four equal servings throughout the day (five grams each). The loading dose is typically followed by a maintenance dose of three to five grams per day (or 0.1 gram per kilogram bodyweight).
Take with Food
Although creatine taken without other foods has been shown to effectively increase total muscle creatine levels, taking either with carbohydrates or with carbohydrates and protein appear to improve retention. (23)(24) Shoot for about 95 grams of carbohydrate or 45 to 48 grams each carbohydrate and protein. (25)
Common carbohydrate sources used in creatine studies are dextrose and glucose. Although studies commonly use powdered dextrose or glucose, these carbs are found in starchy foods and non-fruit sugars (i.e. corn flour, pastas, rice). A convenient protein source may be a post-workout protein powder.
Consistent Use vs. Cycling
Little scholarly evidence currently informs whether creatine should be cycled (e.g. eight to 12 weeks “on,” followed by four to six weeks “off”) or taken consistently at a maintenance dose. Mechanistically, there does not seem to be a strong rationale behind cycling creatine — Again, creatine is not a steroid, so there is not a risk of “resistance” as a result of prolonged use.
Long-term studies illustrate the safety of consistent creatine supplementation for as long as five years of consistent use. (1) Moreover, since excess creatine is ultimately excreted in the urine (similar to vitamin C), the risk of “overdose” appears low. (25)
Should one decide to “cycle off” creatine, they are still likely to experience benefits for weeks, even months following your last dose.
These commonly claimed downsides of creatine are not found in the “Side Effects” section, because none have been substantiated by high-quality studies (i.e. randomized and placebo-matched trials).
The claim to hair loss comes from a 2009 creatine study among rugby players who showed an increase in dihydrotestosterone, a hormone occasionally linked to hair loss. (4)(26) To be clear, none of the rugby players were reported to lose hair or go bald, and follow-up studies assessing the effects of creatine on testosterone and related hormones are equivocal. (4)
The kidney damage claim appears to stem largely from anecdote and confusion. Creatinine is commonly used as a marker of kidney damage when found in high concentrations in the urine. While it is true that some excess creatine may be discarded in the form of creatinine in the urine, it does not necessarily indicate the kidneys are being damaged or overloaded. (4)
Despite creatine being used in some trials as a treatment for the sequelae of kidney disease, Kim and colleagues conservatively recommended individuals at increased risk of kidney issues (e.g. diabetics, those with hypertension, pre-existing kidney dysfunction) avoid creatine supplementation. (1)(20) As always, check with your doctor.
Busy lifters commonly prepare their food and supplements in advance. Whether you’re facing a busy day or setting yourself up for a successful week, pre-mixing creatine into your meal replacement drink, pre-workout supplement, or post-workout protein shake may be a convenient method of sticking to your supplementation schedule.
But you wouldn’t want to sacrifice the efficacy of the supplement for convenience. Fortunately, the U.S. Food and Drug Administration (FDA) has measured the stability of creatine monohydrate powder under various conditions. Minimal degradation occurs when creatine is mixed and stored in neutral pH liquids. (6). Milk-based drinks are included in this category.
As the pH of the liquid is lowered, stability of creatine decreases, with losses of 12% reported following 72-hours storage at 4.5 pH. (6) If you wish to pre-mix your creatine in liquid in a non-neutral pH beverage such as fruit juice or a fruit smoothie, refrigeration likely slows degradation. (6)
Take note: some manufacturers add creatine monohydrate to energy drinks. However, since creatine is known to degrade in low pH solutions, you may wish to avoid creatine/energy drink combos, as the low pH (e.g. pH 2.5- 4.0) paired with long durations non-refrigerated storage has likely reduced the potency of the creatine supplement. Therefore, creatine in acidic shelf-stable energy drinks or pre-workout concoctions appears to be more gimmick than gains.
Creatine and caffeine are among the most studied (and most supported) performance-enhancing supplements. Naturally, it follows that many might wish to combine the two. A recent systematic review reported mixed results of co-supplementation protocols of creatine and caffeine. (27) Two studies showed blunted benefits and one study showed synergistic effects of concurrent supplementation. (27)
Now, when creatine and caffeine are co-ingested — taken together or in a close timeframe of one another — anecdotal and scholarly evidence suggests the very real possibility of gastrointestinal distress. (28)
Altogether, logical recommendations for those wishing to combine creatine and caffeine are to: 1 — separate consumption throughout the day, and 2 — limit caffeine consumption to moderate or low intake during the initial “loading phase” of creatine supplementation.
Another study looked at creatine in combination with beta-alanine regarding cycling performance and reported no apparent synergistic effects. (29) More research is needed on the potential effects of combining creatine with other common sports supplements.
At times, supply chain disruptions have occasionally made it difficult to maintain consistency with creatine monohydrate supplementation. Next time you run out and your favorite retailer is sold out, don’t panic. You likely have four to six weeks before your supplemented and fully-saturated creatine levels in your muscle return to baseline. (1)(30)
Even after muscle creatine concentrations return to baseline, you are likely to enjoy a prolonged twilight period where gains made during supplementation persist.
Creatine monohydrate is far and away the most studied form of creatine. Although other forms often claim superiority in their advertising materials for “better retention” or “increased uptake,” these claims are unsubstantiated by the current body of research (or patently false). (1)
Not only do other forms of creatine tend to be similar or inferior to monohydrate in effectiveness, they also tend to be more expensive. At the time of this writing, only creatine monohydrate has achieved the FDA status of “generally recognized as safe” (G.R.A.S). (7) Until convincing data on other formulations is presented, stick with tried-and-true monohydrate.
G.R.A.S. for Mass (with a Disclaimer)
Few, if any, supplements are as well-studied as creatine monohydrate. The scientific research is virtually overwhelming, but if you’re still searching for an anecdote, I’ve taken a creatine monohydrate maintenance dose for over 10 years with minimal interruptions. My wife, my mother, and, occasionally, even my dog supplement with creatine monohydrate — it’s unlikely many lifters would be comfortable giving other sports supplements to any one of those three case studies, let alone all three.
But this article should not be considered an endorsement or nutritional advice — it is simply a brief review of relevant literature. Consult your physician, sports dietician, or veterinarian for individualized advice.
- Kreider, R. B., 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(1), 18.
- Kerksick, C. M., et al. (2018). ISSN exercise & sports nutrition review update: research & recommendations. Journal of the International Society of Sports Nutrition, 15(1), 38.
- Thomas, D. T., et al. (2016). Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: nutrition and athletic performance. Journal of the Academy of Nutrition and Dietetics, 116(3), 501-528.
- Antonio, J., et al. (2021). Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show?. Journal of the International Society of Sports Nutrition, 18(1), 13.
- 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, 1349-1362.
- U.S. Food & Drug Administration. GRAS Notices. Available online: https://www.fda.gov/media/143525/download (Accessed April 17, 2023).
- Kreider, R. B.,et al. (2022). Bioavailability, efficacy, safety, and regulatory status of creatine and related compounds: A critical review. Nutrients, 14(5), 1035.
- Mills, S., et al. (2020). Effects of creatine supplementation during resistance training sessions in physically active young adults. Nutrients, 12(6), 1880.
- Devries, M. C., & Phillips, S. M. (2014). Creatine supplementation during resistance training in older adults—a meta-analysis. Medicine & Science in Sports & Exercise, 46(6), 1194-1203.
- Doma, K., et al. (2022). The paradoxical effect of creatine monohydrate on muscle damage markers: A systematic review and meta-analysis. Sports Medicine, 52(7), 1623-1645.
- Cooke, M. B., et al. (2009). Creatine supplementation enhances muscle force recovery after eccentrically-induced muscle damage in healthy individuals. Journal of the International Society of Sports Nutrition, 6(1), 13.
- de Salles Painelli, V., et al. (2014). Creatine supplementation prevents acute strength loss induced by concurrent exercise. European Journal of Applied Physiology, 114(8), 1749-1755.
- Tack, C. (2016). Dietary supplementation during musculoskeletal injury: Protein and creatine. Strength & Conditioning Journal, 38(1), 22-26.
- Elosegui, S., et al. (2022). Interaction between caffeine and creatine when used as concurrent ergogenic supplements: a systematic review. International Journal of Sport Nutrition and Exercise Metabolism, 32(4), 285-295.
- Hespel, P., et al. (2001). Oral creatine supplementation facilitates the rehabilitation of disuse atrophy and alters the expression of muscle myogenic factors in humans. The Journal of Physiology, 536(2), 625-633.
- Mistry, D., Lee, P., & Gee, T. (2022). Systematic review for protein and creatine supplements in peri-operative period in elective musculoskeletal surgery-knee and hip replacement. Journal of Arthritis, 11(1), 6-10.
- Rae, C., et al. (2003). Oral creatine monohydrate supplementation improves brain performance: a double–blind, placebo–controlled, cross–over trial. Proceedings of the Royal Society of London. Series B: Biological Sciences, 270(1529), 2147-2150.
- McMorris, T., et al. (2007). Creatine supplementation, sleep deprivation, cortisol, melatonin and behavior. Physiology & Behavior, 90(1), 21-28.
- McMorris, T., et al. (2007). Creatine supplementation and cognitive performance in elderly individuals. Aging, Neuropsychology, and Cognition, 14(5), 517-528.
- Kim, H. J., et al. (2011). Studies on the safety of creatine supplementation. Amino acids, 40, 1409-1418.
- Ziegenfuss, T. N., et al. (1998). Acute fluid volume changes in men during three days of creatine supplementation. Journal of Exercise Physiology, 1(3), 1-9.
- de Guingand, D. L., et al. (2020). Risk of adverse outcomes in females taking oral creatine monohydrate: A systematic review and meta-analysis. Nutrients, 12(6), 1780.
- Greenwood, M., et al. (2003). Differences in creatine retention among three nutritional formulations of oral creatine supplements. Journal of Exercise Physiology Online, 6(2), 37-43.
- Preen, D., et al. (2003). Creatine supplementation: a comparison of loading and maintenance protocols on creatine uptake by human skeletal muscle. International journal of sport nutrition and exercise metabolism, 13(1), 97-111.
- Naderi, A., et al. (2016). Timing, optimal dose and intake duration of dietary supplements with evidence-based use in sports nutrition. Journal of Exercise Nutrition & Biochemistry, 20(4), 1.
- Van der Merwe, J., et al. (2009). Three weeks of creatine monohydrate supplementation affects dihydrotestosterone to testosterone ratio in college-aged rugby players. Clinical Journal of Sport Medicine, 19(5), 399-404.
- Elosegui, S., et al. (2022). Interaction between caffeine and creatine when used as concurrent ergogenic supplements: a systematic review. International Journal of Sport Nutrition and Exercise Metabolism, 32(4), 285-295.
- Trexler, E. T., & Smith-Ryan, A. E. (2015). Creatine and caffeine: considerations for concurrent supplementation. International Journal of Sport Nutrition and Exercise Metabolism, 25(6), 607-623.
- Stout, J. R. (2006). Effects of twenty-eight days of beta-alanine and creatine monohydrate supplementation on the physical working capacity at neuromuscular fatigue threshold. The Journal of Strength & Conditioning Research, 20(4), 928-931.
- Preen, D., et al. (2003). Creatine supplementation: a comparison of loading and maintenance protocols on creatine uptake by human skeletal muscle. International Journal of Sport Nutrition and Exercise Metabolism, 13(1), 97-111.
Featured Image: Enfoca y dispara / Shutterstock