In a very short time, creatine has gone from being seen as "something for bodybuilders" to becoming one of the trendiest supplements among strength trainers, seniors, women in perimenopause, and even professionals with high mental demands. It's increasingly discussed in doctors' offices, pharmacies, social media, and the news media, which has sparked both interest and questions.
Much of its popularity stems from the fact that it's one of the most studied supplements in the fields of sports and health . However, the media hype has also fueled myths and unfounded uses. Experts in nutrition, medicine, and pharmacy from Spain and across Europe remind us that creatine can be useful in many contexts, but only if you fully understand how it works, who it's suitable for, and how to take it.
What is creatine and what function does it have in the body?
Creatine is an organic compound made up of amino acids that the body produces in organs such as the liver, kidneys, and pancreas, and that we also obtain through food. It is stored primarily in skeletal muscle in the form of phosphocreatine , a kind of "emergency battery" that helps regenerate ATP (adenosine triphosphate) , the main energy currency of our cells.
This quick energy reserve is key during short bursts of intense effort , such as weightlifting, sprinting, or high-intensity interval training. In those seconds when the body is going all out, creatine helps muscles continue to contract powerfully before fatigue sets in, which is why it's so beneficial for improving performance and repetition capacity.
A smaller fraction of creatine is also found in other tissues, such as the brain and heart . There, it plays a similar role: facilitating the rapid availability of energy to cells when demand increases, which is relevant in contexts of high cognitive demands, stress, or lack of sleep.
Naturally, our reserves are limited and are depleted with exertion . The body replenishes them through diet and internal synthesis, but this process isn't immediate. That's why creatine supplements have gained popularity: they allow for sustained muscle protein stores.
Which form of creatine is most effective
There are many forms of creatine available on the market, but experts agree that creatine monohydrate is the most scientifically supported . The International Society of Sports Nutrition has already stated in a position paper that this is the most studied, effective, and safe option when used at the recommended doses.
Among monohydrates, variants like micronized creatine have become popular . It's essentially the same compound but with smaller particles. This characteristic facilitates its dissolution and, in some people, may improve digestive tolerance, although no drastic differences in results have been observed compared to the standard form.
Other forms also exist (creatine HCl, creatine citrate, and various salts), which are often marketed with ambitious claims. However, the available evidence continues to favor creatine monohydrate as the gold standard: it is the form with the most long-term studies on both performance and safety.
Besides the chemical form, product quality matters . As sports nutritionists warn, initial impurities act as starting points for chemical reactions that promote degradation when exposed to heat or light. In practice, this means that cheap, poorly purified creatine may be less stable than creatine with more stringent quality controls, although it is not necessarily toxic.
Capsules, powder, gummies… which format to choose?
Creatine is sold in many forms: powder to mix with water or other beverages , dosed capsules, single-dose sachets, and even sugar-flavored gummies . In terms of effectiveness, the determining factor is the amount of creatine monohydrate ingested consistently, not so much the specific form.
Unflavored powder remains the most common and versatile option because it dissolves in water, milk, juice, or protein shakes, allowing for easy dosage adjustment. Capsules can be practical for those who are sensitive to taste or don't want to weigh grams, as each one usually provides a fixed amount, but they tend to slightly increase the cost of the treatment.
In the case of fortified gummies , their appeal usually lies more in their palatability than in their cost or creatine density. Some include other ingredients such as taurine or B vitamins to boost energy levels, although it's advisable to carefully check the labeling to avoid confusing a functional candy with an actual creatine supplement.
For people with very specific diets (for example, vegans or those following kosher or halal guidelines ), there are already creatine supplements on the market certified as suitable for these profiles. In Europe, many are produced under strict pharmaceutical standards, with purity levels exceeding 99,9%, according to the manufacturers themselves.
What are the benefits of creatine on athletic performance?
In the realm of exercise, creatine is probably the most scientifically supported supplement . Studies show that it helps improve the ability to perform anaerobic work , that is, intense efforts of short to medium duration, typical of strength, speed, or intermittent sports.
When muscle creatine stores are more replenished, the availability of phosphocreatine increases, which promotes rapid ATP resynthesis during contractions. This translates into being able to perform a few extra repetitions, lift heavier weights, or maintain intensity for more sets—something especially relevant for elite athletes, where a few hundredths of a second or a few extra kilograms can make all the difference.
Sustained supplementation has also been linked to improved recovery after exercise , reduced muscle damage, and less post-workout soreness, which in turn facilitates more frequent and consistent training. Furthermore, creatine may contribute to reducing the risk of certain injuries and improving the body's ability to adapt to strength and power training.
In the general population that trains at the gym, creatine is primarily used to increase lean muscle mass , improve strength, and feel more energetic during workouts. It is not a substitute for a well-planned training program, but it does act as an additional ergogenic aid that, combined with a good program, can enhance results.
Beyond sport: creatine, health and brain
In recent years, scientific interest has also shifted towards the potential health benefits of creatine beyond physical performance . Various studies point to its potential in contexts such as aging, neurodegenerative diseases, and situations of high cognitive demand , although many of these are still in their early stages.
Position papers and recent reviews indicate that creatine may have clinical utility in conditions such as muscular dystrophy, Parkinson's disease, diabetes, osteoarthritis, fibromyalgia, cerebral or cardiac ischemia, depression in adolescents, or complications during pregnancy . The key word is "potential": the evidence is promising but not conclusive, so further studies with specific protocols are needed.
Where the body of evidence is growing strongest is in the field of neurodegenerative diseases and cognitive deficits . By improving neuronal energy metabolism, creatine could help protect against certain types of damage, or at least support brain function in contexts of stress, sleep deprivation, or age-related decline.
Nutrition and science experts in Spain suggest that people who need to maintain a high level of attention or concentration for extended periods could benefit from well-planned supplementation. Its role in recovery after traumatic brain injuries , where a true "energy crisis" occurs at the neuronal level, is also being studied .
Creatine in women, older people, and sedentary lifestyles
A striking aspect of recent literature is the emphasis on groups traditionally overlooked in supplementation studies: women aged 40-45 and over, older adults, and individuals with low levels of physical activity . In fact, hundreds of academic articles have already been published focusing on the effects of creatine in women from middle age onward.
Several healthcare professionals point out that creatine reserves in women tend to be somewhat lower , so an external supplement could offer a greater margin of improvement. In Spain, pharmacists and nutritionists indicate that creatine can be particularly beneficial during stages such as perimenopause and menopause , both for its impact on muscle mass and for its potential effects on brain fog.
The improvement of mental clarity, focus, and mood is something that numerous studies are beginning to explore, and which doctors and social media communicators are also reporting in their clinical experience. In older adults, creatine is being studied as a support for maintaining functional independence, strength, and cognitive reserve , helping to prevent or delay sarcopenia (age-related muscle loss).
In sedentary or inactive individuals, specialists indicate that creatine can help preserve muscle mass and maintain functional muscle, which has a positive impact on metabolic health, bone density, and cardiovascular protection. This doesn't mean it replaces exercise, but it can serve as a bridge during periods of reduced activity (peak workloads, recovery processes, or transition periods before resuming training).
Common myths: Does it cause weight gain, water retention, or kidney damage?
Numerous myths surround creatine, many of them deeply ingrained. One of the most common, especially among women, is the idea that it causes weight gain or water retention . What actually happens is an increase in intracellular hydration : more water enters the muscle, which is actually desirable because it improves muscle function and can contribute to firmer-looking skin.
In healthy individuals, available evidence has not shown that creatine causes kidney or liver damage, cramps, dehydration, or hair loss . Some studies have observed a slight increase in blood creatinine levels with creatine supplementation, but this is a physiological change resulting from increased creatine availability, not an impairment of kidney function itself.
Another recurring concern is whether “creatine damages the kidneys .” Scientific reviews indicate that, at typical doses (3-5 g daily) and in individuals without known kidney disease, no significant adverse effects have been observed. Even so, healthcare professionals emphasize the need to use the supplement responsibly , maintaining adequate hydration and undergoing regular medical checkups when appropriate.
The situation is different for those who already have chronic kidney disease, proteinuria, poorly controlled hypertension, or other impaired kidney function . In these cases, the general recommendation is to avoid creatine or use it only under strict medical supervision , as any unnecessary overload can be problematic.
Who should not take creatine (or should exercise extreme caution)
Although creatine has a very favorable safety profile in the general population , it is not a supplement for everyone or in every circumstance. Before starting, experts recommend always consulting a healthcare professional about your individual situation.
In general, its use without supervision is not recommended in people with diagnosed kidney disease , as well as in those with a history of kidney problems, persistent proteinuria, or treatments that may interfere with kidney function. It is also prudent to consult a doctor in cases of liver disease, even though available data do not indicate a direct toxic effect on the liver of healthy individuals.
Pharmacists and nutritionists also point out that pregnant women, breastfeeding mothers, children, and adolescents should not take creatine on their own. The lack of robust studies in these groups means that, as a precaution, its use is recommended unless specifically indicated and under specialized supervision.
In any case, both in Spain and in other European countries, the recommendation is the same: “taking creatine is not mandatory to be healthy .” The foundation of good health remains a balanced diet, adequate rest, and regular exercise. Creatine, when it makes sense, complements this foundation, it doesn't replace it.
Dosage, timing of intake, and consistency
One of the points most emphasized in scientific publications is that creatine doesn't work as a one-off stimulant , nor is it something that makes sense to take only on days of intense training. Its effect occurs through accumulation in the muscle , gradually saturating phosphocreatine stores.
Therefore, the recommendation repeated in consultations, pharmacies, and professional networks is simple: the important thing is to take it every day , integrating it into your routine so that it's easy to remember. Focusing more on daily consistency than on the exact minute of intake usually makes a bigger difference in the long run.
In healthy adults, the most common dosage is between 3 and 5 grams per day . Some people choose to do a short "loading" phase (for example, about 20 g daily divided into several doses for a few days) to saturate their stores more quickly, and then switch to a maintenance dose. Others skip the loading phase and maintain a low dose from the beginning; the end result is similar, although saturation takes a little longer to reach its maximum.
Regarding the ideal timing, there are nuances: taking creatine before training could promote muscle pump and nutrient delivery to the muscles during the session, while taking it afterward would take advantage of improved insulin sensitivity, facilitating its absorption. The difference isn't dramatic, so many professionals advise simply taking it with a meal or during the workout itself, whichever is more convenient.
Common mistakes that reduce its effectiveness
Although creatine powder is a very stable product when dry and properly sealed , certain everyday habits can contribute to its degradation once dissolved. Sports nutritionists in Spain point out that these mistakes are not usually dangerous, but they do make the supplement less effective than it could be.
One of the most common mistakes is preparing the shake hours in advance and leaving it in the shaker until it's time to drink it. The longer the creatine remains in solution, the greater the chance that it will degrade slightly into compounds like creatinine or hydantoin. It doesn't pose a serious risk, but some of the product is being wasted.
Another common mistake is mixing creatine with coffee or other very hot drinks and letting the mixture sit. Above about 60 degrees Celsius (140 degrees Fahrenheit), heat promotes its breakdown. Those who prefer to take it with coffee can do so, but it's best to opt for lukewarm or cold coffee and drink it immediately after preparing it, without leaving it sitting on the table for half an hour.
Leaving the shaker in the sun, inside the car, or in your gym locker for hours with the creatine already dissolved doesn't help either. The combination of light, heat, and time is precisely what you want to keep the supplement stable, especially if it's not high-purity creatine.
Experts summarize the correct approach in a series of simple recommendations: store the container in a cool, dry place , tightly sealed; mix the portion just before taking it ; do not expose the preparation unnecessarily to heat; and choose products of proven quality instead of focusing solely on the price.
What science says about safety and medium-term effects
Creatine is currently one of the most researched supplements in humans in the field of sports and nutrition. Years of trials and follow-up studies have confirmed both its effectiveness in certain contexts and its safety when used in recommended amounts.
International scientific reviews and positions from specialized societies agree that creatine monohydrate is safe in healthy individuals, even with prolonged use, provided that dosages are respected and adequate hydration is maintained . No direct link has been found between its responsible use and an increased risk of kidney, liver, or cardiovascular disease.
However, the authors of these studies themselves point out that this does not mean creatine is necessary for everyone , nor that any combination with other substances or medications is without risk. Therefore, they emphasize the importance of consulting with healthcare professionals —doctors, nutritionists, pharmacists—before incorporating it into your routine, especially if you are taking medication chronically or have pre-existing conditions.
Meanwhile, the rise in popularity of this supplement has brought with it a phenomenon that worries some experts: many people are consuming creatine without a clear understanding of its purpose , influenced by simplistic messages or recommendations on forums and social media. Hence the emphasis on informed, contextualized use, tailored to each individual's specific goals.
With the volume of studies published each year and the growing interest in its role beyond the gym, creatine has established itself as a useful and versatile tool, provided it is used judiciously: choosing well-studied forms such as monohydrate, carefully controlling the dosage, avoiding mistakes that promote its degradation, and above all, consulting with professionals before incorporating it into your routine, especially in Europe, where health and pharmaceutical advice is accessible and can make the difference between a well-utilized supplement and just another bottle in the cupboard.