Recently, I started thoroughly researching the whole creatine topic because I see it everywhere: gyms, social media, clinics. Basically, everyone talks about it as if it were the ultimate solution for gaining muscle and improving brain function. But I decided to check what science really says about what creatine does in the body.

The interesting thing is that creatine is literally one of the most studied supplements out there. There are hundreds of randomized clinical trials on this. The International Society of Sports Nutrition confirms that it works to improve performance in intense exercises when combined with strength training. But here’s the key point: creatine alone does nothing. You need to be seriously training.

So then, what does creatine actually do in the body? In the first days, especially if you do a loading phase, the increase in volume you see is mainly water inside the muscle cells. It’s an osmotic effect that gives you that feeling of more 'filled' muscles, but it’s not pure muscle gain. In the medium term, if you keep training with intensity, there are real hypertrophy gains, although the magnitude is limited.

A topic that causes anxiety is the 'rebound effect.' According to data, when you stop taking creatine, levels return to normal in 5 to 8 weeks. The first thing that goes is intracellular water, which is why you see a slight weight reduction. But the muscle mass gained through training remains if you keep exercising. The safe dose is 3 to 5 grams daily in healthy people, but always consult an expert.

Now, the cognitive side is where things get more complicated. The brain consumes about 20% of the body's total energy, and creatine is involved in the rapid production of ATP, which is the energy currency of cells. In theory, what creatine does in the body should include brain improvements, right? But in practice, the results are much more modest. In healthy, rested individuals, cognitive benefits are small or almost null. Some effects are seen in situations of energy stress, such as severe sleep deprivation. Improvements in verbal memory and processing speed are observed, but they remain limited.

Regarding neurological diseases, studies on Parkinson’s, Huntington’s, and ALS have not shown significant clinical benefits. In Alzheimer’s, there are preliminary investigations, but we are in the pilot phase. So, the neuroprotective promise remains just that: a promise.

The conclusion is clear. Creatine has solid scientific backing as a performance enhancer in intense exercises when combined with structured training. In the cognitive aspect, the evidence is promising but incomplete. It’s not the miracle supplement sold on social media. It works in specific contexts with clear indications. As always in health, the key is to differentiate what has a reasonable biological basis from what truly demonstrates proven clinical benefit. If you’re at the gym and train hard, it might be worth trying. If you’re looking to improve your memory by taking creatine without doing anything else, better save that money.