Does Creatine Cause Water Retention?

Why Creatine Is So Widely Used

Creatine is one of the most researched supplements in sports nutrition and is widely used to support strength, power, and muscle performance.

One of the main ways creatine works is by helping muscles produce more adenosine triphosphate (ATP), the primary energy source used during short bursts of high-intensity exercise such as weightlifting or sprinting.

By supporting ATP production, creatine can help athletes perform more repetitions, lift heavier weights, and train at higher intensity, which may contribute to greater strength and muscle development over time.

Given an important factor in muscle growth is progressive overload (adding more weight to the bar) you're putting yourself into a position for success!

And when research examines the role of creatine on muscle growth directly, it comes up favourably; those who take creatine can double the amount of muscle growth compared to those who don't.

There's also strong research to say creatine won't just benefit your physical performance but enhance brain function and memory, too.

Despite its strong research support, creatine is often surrounded by myths — one of the most common being that it causes unwanted water retention.

Creatine and Water Retention

The idea that creatine causes water retention comes largely from early research examining high-dose creatine supplementation.

One early study from the 1980s found that taking around 20 grams of creatine per day for several days increased total body water. However, this dose reflects a short-term loading phase, not the typical daily maintenance intake of 3–5 grams per day. 

Creatine is an osmotically active compound, meaning it draws water into muscle cells as creatine is stored. This can lead to a small increase in intracellular water, which is the water stored inside muscle cells.

To understand this better:

When creatine increases intracellular water within muscle cells, this can sometimes be interpreted as “water retention,” particularly during the first few days of supplementation.

What About Long-Term Water Retention?

Research examining longer-term creatine supplementation generally shows no meaningful increase in total body water relative to muscle mass.

For example, one study using a typical creatine protocol - around 20 g per day for 7 days followed by 5 g per day for four weeks - reported no significant changes in total body water, extracellular water, or intracellular water.

Other studies using maintenance doses of around 0.03 g per kilogram of body weight per day for several weeks also found no increase in total body water.

Some research has reported small increases in total body water during creatine supplementation. However, these changes typically occur alongside increases in lean muscle mass, meaning the additional water is largely stored within muscle tissue rather than as unwanted fluid retention.

This type of intracellular water increase is not considered harmful and may actually support muscle function and protein synthesis.

So, Does Creatine Cause Water Retention?

Current research suggests that creatine supplementation does not lead to problematic long-term water retention.

While short-term increases in water inside muscle cells can occur during the early stages of supplementation, studies generally show no significant long-term increase in total body water relative to muscle mass.

Much of the water associated with creatine is stored inside muscle cells (intracellular water), which is part of the normal process of increasing muscle energy stores and supporting training performance.

Overall, the evidence indicates that creatine remains a safe and effective supplement for supporting strength, muscle growth, and high-intensity training, with minimal concern about long-term water retention when used at recommended doses.