Creatine: performance or marketing?

More and more often, during consultations and programs dedicated to metabolic health, sports, and longevity, I find myself talking about creatine. A supplement still surrounded by many clichés, but which scientific research is currently observing with much broader interest than in the past.

In recent years, creatine has left the gyms and entered conversations about longevity, metabolic health, muscle recovery, and performance.

There are those who still consider it a “bodybuilder” supplement.
Those who demonize it.
And those who take it without really knowing what it does.

Yet today, creatine is one of the most thoroughly studied supplements in scientific literature, with a role that goes far beyond aesthetics or increasing muscle mass.

Indeed, more and more studies are linking it to themes such as:

• strength and physical performance
• muscle recovery
• energy metabolism
• active aging
• metabolic health
• prevention of frailty

So: does creatine really work?
And above all: for whom can it be useful?

Creatine is a substance naturally present in our body and involved in the rapid production of cellular energy.

It is synthesized primarily by the liver, kidneys, and pancreas from amino acids such as arginine, glycine, and methionine, while a portion comes from our diet, especially from meat and fish.

Muscle contains large amounts of it because it uses it during short and intense efforts. But its role is not just about sports performance.

Today we know that creatine is involved in processes related to:

• cellular energy
• recovery
• effort adaptation
• muscle function
• energy metabolism

And this is precisely why scientific research is also observing creatine in the context of longevity and healthy aging.

Today, studies are also observing creatine for its possible role in brain energy metabolism. Some evidence, in fact, suggests potential interest in contexts of intense cognitive demand, metabolic stress, sleep deprivation, and aging, although many applications are still under study.

It is also important to remember that creatine is not a doping substance, but a compound naturally present in our body and in food.

More and more teenagers are taking creatine.

But the main point is not the supplement itself.
It is the metabolic and behavioral context in which it is used.

Because many young people today:

• sleep little
• recover poorly
• follow unbalanced diets
• overtrain or train without a plan
• seek quick results
• live under chronic stress

Under these conditions, no supplement can compensate for fragile physiological foundations.

Studies suggest that in young athletes who are well-trained and professionally guided, creatine can support:

• explosive activities
• workout quality
• muscle recovery
• strength production

But always within an integrated approach that includes:

• proper nutrition
• correct protein intake
• hydration
• sleep
• structured training

For minors, professional supervision remains essential.

One of the most interesting topics today concerns menopausal women.

With the drop in estrogen, the muscle also changes:

• strength decreases
• recovery worsens
• risk of muscle loss increases
• body composition changes
• insulin sensitivity worsens

And this is where strength training, proper nutrition, and in some cases creatine can become interesting prevention tools.

Not to “become muscular”. But to preserve:

• energy
• metabolic function
• quality of life
• bone health

As we age, preserving muscle mass effectively means preserving metabolism, independence, and quality of life. This is also why creatine is being studied more and more often today in the context of sarcopenia and aging.

Dietary creatine is found mainly in meat and fish.

For this reason, vegetarians and vegans often tend to have lower muscle stores compared to omnivores.

Some studies suggest that in these individuals, supplementation may show more evident effects on muscle energy availability and physical performance.

Naturally, in this case too, it is important to evaluate the general context:

• diet quality
• protein intake
• physical activity level
• overall nutritional status

For years we have talked about muscle almost exclusively in aesthetic terms.

Today, however, longevity medicine shows us that muscle is central to:

• glycemic metabolism
• insulin sensitivity
• hormonal balance
• prevention of frailty
• bone health
• autonomy over time
• aging quality

This is why talking about creatine today also means talking about prevention, cellular energy, and metabolic health.

Creatine is not a “foreign” substance to our body.
We already consume it naturally through certain foods, especially meat and fish, as well as producing a portion on our own.

For this reason, not everyone necessarily needs to supplement it.

In sedentary individuals with a good diet, the amounts present in the body can often be sufficient for normal daily needs.

However, the situation can change in specific situations, such as:

• intense and regular workouts
• high muscle demand
• vegetarian or vegan diets
• menopause and muscle aging
• specific performance or recovery goals

In these cases, supplementation can become a useful tool to evaluate together with a professional, always within a broader strategy that includes nutrition, training, sleep, and recovery.

The real difference is not made by the supplement.
It is made by daily habits.

A muscle-friendly strategy could include:

• breakfast with high-quality proteins
• regular physical activity
• strength training at least twice a week
• proper post-workout recovery
• adequate intake of leucine and essential amino acids
• quality sleep
• adequate hydration
• balanced protein distribution across main meals

Among the foods naturally rich in leucine we find, for example:

• eggs
• Greek yogurt
• Parmesan cheese
• fish
• whey protein

In this context, if necessary, creatine can represent an additional support, not a magic solution.

The most widely shared guidelines today primarily suggest:

• creatine monohydrate
• daily intake
• about 3–5 g per day in most healthy adults

The International Society of Sports Nutrition defines creatine monohydrate as one of the most studied supplements with the best safety profile available today in sports nutrition, when used correctly in healthy individuals.

According to available scientific evidence, no clinically relevant adverse effects emerge in healthy subjects taking creatine at recommended doses.

In the presence of pathologies, pharmacological therapies, or specific clinical conditions, it remains important to consult a healthcare professional.

This is probably the question I receive most often.

For years, creatine has been associated with the idea of possible “renal stress”.
Today, however, the scientific evidence is much clearer.

In healthy subjects, at the recommended dosages, creatine monohydrate has not shown significant adverse effects on kidney function in the majority of available studies.

Pay attention, however, to an important aspect: creatine can temporarily increase creatinine in the blood, but this does not necessarily mean kidney damage.

Creatinine is, in fact, a metabolite derived also from the metabolism of creatine itself. For this reason, in those who take creatine, some tests may appear altered without there being a real worsening of kidney function.

Not exactly.

Safety depends on:

• health status
• dosages
• product quality
• hydration
• any pre-existing conditions

Caution is important, especially in the presence of:

• kidney failure
• chronic kidney diseases
• nephropathies
• uncontrolled hypertension
• complicated diabetes
• use of potentially nephrotoxic drugs

In these cases, supplementation should always be evaluated with a doctor or specialist.

At the most common dosages (3-5 g/day), creatine is generally well tolerated.

The most frequent side effects are:

• mild initial water retention
• increase in body weight related to intracellular water
• abdominal bloating in some individuals
• gastrointestinal issues, especially with high doses or improper intake

Intestinal issues tend to appear mainly:

• with excessively high doses
• with aggressive loading phases
• if taken without adequate hydration
• with poor quality products

The guidelines of the International Society of Sports Nutrition consider creatine one of the most studied supplements with the best safety profile in healthy individuals, even in the long term.

Many myths stem from:

• old isolated case reports
• improper uses
• excessive dosages
• combinations with other substances
• incorrect interpretations of blood tests

Creatine should not be seen as a supplement “to take on your own”.

It must always be included in a context that involves:

• proper nutrition
• correct physical exercise
• recovery
• hydration
• personalized clinical evaluation

Because even the most studied supplement in the world cannot replace a well-built metabolic strategy.

Creatine is not a magic formula.
And it does not replace lifestyle, training, or nutrition.

But today, scientific research shows us that, in some contexts, it can represent an interesting tool to support:

• performance
• strength
• recovery
• muscle metabolism
• active aging

Perhaps today the real question is no longer whether creatine is only for bodybuilders.
But how much muscle (and cellular energy) influences our health over time.

Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017;14:18. Published 2017 Jun 13.
https://pmc.ncbi.nlm.nih.gov/articles/PMC5469049/

Li N. Creatine supplementation and exercise in aging: a narrative review of the muscle-brain axis and its impact on cognitive and physical health. Front Nutr. 2026;12:1687719. Published 2026 Jan 12.
https://pmc.ncbi.nlm.nih.gov/articles/PMC12832544/

Jagim AR, Kerksick CM. Creatine Supplementation in Children and Adolescents. Nutrients.
2021;13(2):664. Published 2021 Feb 18.
https://pmc.ncbi.nlm.nih.gov/articles/PMC7922146/

Smith-Ryan AE, DelBiondo GM, Brown AF, Kleiner SM, Tran NT, Ellery SJ. Creatine in women’s health: bridging the gap from menstruation through pregnancy to menopause. J Int Soc Sports Nutr. 2025;22(1):2502094.
https://pmc.ncbi.nlm.nih.gov/articles/PMC12086928/