Table of Contents

Not a Steroid

Creatine is a natural nitrogenous compound synthesized in the liver and kidneys from three amino acids: glycine, arginine, and methionine. It is not a hormone, does not affect the hormonal axis (testosterone), and is classified as a safe dietary supplement (GRAS) by the FDA and ANVISA, being the most studied ergogenic aid in the history of sports nutrition.

1. Introduction: The "Steroid" Stigma

For decades, creatine was unfairly associated with anabolic steroid use, kidney damage, and harmful water retention ("bloating"). This stigma kept many patients away who could benefit greatly from supplementation, including the elderly, vegetarians, and people with neurodegenerative diseases.

Modern science, however, has completely rehabilitated creatine's image. Today, it is recognized not only as the most effective supplement for gaining strength and lean mass but as a conditionally essential nutrient with potent neuroprotective and metabolic effects.

2. Biochemistry: The ATP-CP System

To understand how creatine works, we need to look at the cell's energy currency: ATP (Adenosine Triphosphate). When ATP releases energy, it loses a phosphate and becomes ADP (Adenosine Diphosphate).

Creatine stored in the muscle (in the form of Phosphocreatine) quickly donates its phosphate group to ADP, "recycling" it back into ATP. This system, called ATP-CP, is the main energy source for explosive and short-duration efforts (like lifting weights or a 100m sprint).

3. Beyond Muscle: Creatine in the Brain

The brain, although representing only 2% of body weight, consumes 20% of the body's energy. Neurons, like muscle cells, depend on ATP to fire electrical signals.

Studies show that creatine supplementation can increase brain phosphocreatine stores by 5-15%. This translates into:

4. Sarcopenia and Healthy Aging

Sarcopenia (loss of muscle mass and strength with age) is a key predictor of frailty, falls, and mortality in the elderly. Creatine emerges as a critical therapeutic intervention for this population.

"The combination of Creatine + Resistance Training in the elderly results in gains in lean mass and functionality significantly superior to training alone, acting directly against dynapenia (loss of strength)."

Furthermore, creatine may have beneficial effects on bone health and glycemic control (GLUT4 translocation), combating osteosarcopenia and type 2 diabetes.

5. Renal Safety: The End of the Myth

The myth that "creatine is bad for the kidneys" originated from a confusion in interpreting tests. Creatine is metabolized into Creatinine, which is excreted by the kidneys and used as a marker of kidney function.

When supplementing, it is natural for blood creatinine levels to rise slightly (as there is more creatine to be broken down), but this does not reflect a drop in glomerular filtration. It is a false positive.

6. Dosage Protocols: Is Loading Necessary?

There are two main protocols, both effective:

  1. Loading Phase (Saturation): 20g per day (divided into 4 doses of 5g) for 5-7 days, followed by maintenance.
    • Advantage: Fills the muscle tank quickly (1 week).
    • Disadvantage: May cause gastric discomfort and acute bloating.
  2. Constant Dose (Recommended): 3g to 5g per day, every day.
    • Advantage: No side effects, higher adherence.
    • Disadvantage: Takes about 3-4 weeks to reach maximum saturation.

Clinical Tip: Creatine works by accumulation (chronic use), not acute effect. Taking it "pre-workout" makes no immediate difference. Ideally, take it at any time, preferably with a carbohydrate source to optimize absorption via insulin.

7. Monohydrate vs. The Rest

The market offers creatine HCL, ethyl ester, liquid, buffered, etc. Science is clear: Creatine Monohydrate is the most studied, safest, cheapest form with the highest bioavailability (almost 100%).

Other forms often cost more and deliver less (or the same) amount of active creatine to the muscle. The "Creapure" seal guarantees purity and absence of contaminants, being the gold standard of quality.

8. Conclusion

Creatine has transcended the gym environment. It is a pleiotropic molecule with benefits ranging from athletic performance to prevention of frailty in the elderly and cognitive optimization. With an impeccable safety profile at therapeutic doses, it deserves its place as one of the pillars of modern evidence-based nutritional supplementation.

Selected Bibliographic References

[1] 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, 18.
[2] Avgerinos, K. I., et al. (2018). Effects of creatine supplementation on cognitive function of healthy individuals: A systematic review of randomized controlled trials. Experimental Gerontology, 108, 166-173.
[3] Gualano, B., et al. (2012). In sickness and in health: the widespread application of creatine supplementation. Amino Acids, 43(2), 519-529.
[4] 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.
[5] 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.
[6] Wallimann, T., et al. (2011). The creatine kinase system and pleiotropic effects of creatine. Amino Acids, 40(5), 1271-1296.