For decades, creatine has been one of the most studied and commonly used supplements in sports nutrition. Most advice is simple: take about 20 grams per day for a few days to “load”, then maintain with 3-5 grams per day. This saturates muscle creatine stores and helps support strength, power, and performance.

But in recent years, researchers have started asking a different question:
What happens when creatine is studied in the brain?

That question has led researchers to take a closer look at higher creatine doses. They are using higher amounts as a research tool to better understand what creatine does in the body and how it might be useful in more ways than just muscle support.

Muscle Saturates Easily. Your Brain Doesn’t — That Changes Everything

The main reason scientists are studying higher creatine doses is simple: the brain is much harder to saturate with creatine than muscles are.

A landmark brain-imaging study gave healthy adults 20 grams of creatine per day for four weeks. The researchers used brain scans to measure how much creatine built up in the brain over time.  

On average, brain creatine levels increased by about 8–9%, but the results were very different from person to person. People with larger body sizes often showed smaller increases, which suggests that body size can affect how much creatine the brain actually absorbs.

This is very different from skeletal muscle. Muscles usually fill with creatine quickly and reliably using standard loading methods. The brain absorbs creatine more slowly and unevenly. That slower, less predictable process is one of the main reasons scientists are now testing higher doses and longer dosing periods in their research.

Why Researchers Pushed Doses So High in the Sleep Deprivation Study

A 2024 study took this idea even further by testing what happens when people take a much larger dose of creatine during extreme stress on the brain.

In the study, participants were kept awake for 21 hours, which is known to strongly strain the brain’s energy systems. After that, they were given a single high dose of creatine monohydrate — 0.35 g per kilogram of body weight, which works out to about 25 grams for a 150lb (70 kg) adult.

The researchers then measured changes in brain energy markers and tested how well participants performed on different thinking tests. 

The graphic below summarizes what they found.
Compared to the placebo group, the people who took creatine performed better on several cognitive tests, including:

• Word Memory Tests (WMT)

• Forward Digit Span (SPAN)

• Language Processing

• Logic 

• Numeric Reasoning

In simple terms, after severe sleep deprivation, one large dose of creatine helped the brain function better.

Just as important is what the study wasn’t trying to do. The researchers were not suggesting that everyone should start taking 25 grams of creatine every day. They used a high dose as a research tool to see whether quickly increasing creatine levels could help the brain during extreme stress.

This explains why high doses are showing up more often in modern creatine studies:
They allow scientists to explore how creatine works in the brain, where absorption is slower and energy demands are especially high.

The Bigger Picture: What Creatine Is Doing in the Brain

A 2023 review paper pulls these threads together by looking at how creatine affects brain health. The authors explained that creatine plays important roles in the brain, including: 

• Helping manage the brain’s energy supply 

• Neurotransmission

• Cellular protection

Evidence suggests supplementation may influence cognitive performance.

One key point matched what the other studies had already shown: the brain absorbs creatine more slowly and less completely than muscles do. Because of this, dosing strategies used for muscle strength do not directly apply when researchers study the brain. 

This difference is the main reason scientists are taking a new interest in higher creatine doses. They are trying to understand how creatine works in parts of the body outside of muscle, especially in the brain, where absorption and storage follow very different rules. 

What Does This All Mean? 

Seeing 20-25 gram doses in research studies does not mean that everyone should start taking that much creatine.

In simple terms, higher doses appear in research because the brain is much harder to study and support than muscle, not because the basic creatine guidelines have suddenly changed.