Creatine: What It Is and Who Can Benefit from it?

What is creatine?  

Creatine is a naturally occurring compound that's made by the liver and kidneys from three amino acids. It's also found in food, mainly meat and fish, and can be taken as a supplement, which is a manufactured version of the compound. 

Although it’s made from amino acids, creatine isn’t a protein. Instead, think of it as a quick source of energy for your muscles. 

What does it do in the body?  

Creatine is used by tissues that need a lot of energy. Around 95% is stored in your muscles, with the remaining amount stored in the brain and heart. 

Your cells make energy by breaking down glucose into a molecule called ATP (adenosine triphosphate). ATP is often described as a cell's “energy currency” because it stores and releases energy for the cell to use.

The catch is that ATP runs out quickly, especially during intense activity. But the body can rapidly regenerate it - a bit like recharging a battery. And this is where creatine comes in.

Inside your cells, creatine is converted into phosphocreatine (PCr). This helps recycle ATP so your muscles can keep working. This system powers short bursts of activity lasting about 10–15 seconds. Think sprinting, lifting a heavy weight, or any high-intensity effort. 

So, what are the benefits of taking it as a supplement?  

Creatine monohydrate has been heavily studied as a supplement for improving exercise performance. Research shows that increasing creatine stores in muscle can: 

• delay fatigue during short, high-intensity exercise (like sprinting or weightlifting)  
• increase strength and muscle gains when teamed with resistance training, compared to training alone  

In simple terms, it can help you squeeze out an extra rep, help recovery between sets, or help you push a bit harder. Over time, this can lead to better performance and greater muscle gains. 

Could it help offset age-related muscle loss? 

One of the most promising benefits of creatine is supporting muscle health as we age. 

From around the age of 40, we gradually start to lose muscle mass. This is known as sarcopenia. Over time, this affects metabolic health, strength and everyday function, and can increase the risk of falls and fractures. 

Strength training is still the most effective way to slow this process. But studies have found that adding creatine to the diet may give an extra boost, leading to greater gains in muscle mass and strength compared to training alone. 

Creatine and cognitive function  

There’s also growing interest in creatine’s role in brain health. Some early research suggests it may help support memory and cognitive function. 

This is particularly relevant for older adults, who tend to have lower creatine levels. This is partly because the body produces less with age, and partly because muscle mass declines as we get older. 

But the evidence here is still developing. There are no approved health claims yet, and more high-quality research is needed before conclusions can be made about the relationship between creatine and cognitive function.  

How much do I need per day?   

To maximise creatine stores in the muscle, most people need around 3–5 grams per day. The body produces around 1-2 grams, and a mixed diet provides around 0.5–1 gram per day.

However, intakes are lower on a plant-based diet, as creatine is only found in animal foods. People following a plant-based diet therefore tend to have lower creatine stores.

Taking a supplement providing 3–5 grams daily can fully saturate muscle stores in about 3–4 weeks. 

What sort of creatine supplement should I try?  

Creatine monohydrate is the most studied and widely used form. It’s also the one you’ll see most often in supplements. 

More expensive versions are often marketed as being better, but there’s no good evidence to support this. 

How do I take creatine?  

Creatine monohydrate comes as a white powder. You can mix it with water or juice or add to a smoothie. It mixes better with room temperature liquid, and can be added to warm drinks too. Just be aware that at very high temperatures it does begin to degrade.

Are there any downsides?  

Creatine has a good safety profile and is considered safe for most people. 

It draws water into muscle cells, so some people notice a small increase in body weight from extra water when they start using it.

Some people experience digestive symptoms like bloating or diarrhoea, but this is more common with higher doses. Taking 3–5 grams per day is generally well tolerated. 

Could creatine affect my kidneys?  

Creatine is broken down into a substance called creatinine, which is filtered from the blood by the kidneys and removed in urine. 

Creatinine is also used as a marker of kidney function. When you take creatine, blood creatinine levels can rise. This doesn’t mean your kidneys are working less well - it’s often just a result of the supplement itself. 

At recommended doses, there’s no evidence that creatine harms kidney health in healthy adults. Research over the past 20 years has consistently shown it to be safe. 

But if you have pre-existing kidney disease or a kidney condition, you should speak to your doctor before taking creatine.  

Who might benefit from creatine? 

Creatine isn’t essential, but it can be beneficial for the following: 

• If you're doing strength or high-intensity training, regardless of your training level
• Older adults, to help maintain muscle and strength  
• People eating little or no meat or fish, who may have lower creatine stores to begin with  

Because there aren't any good quality trials looking at the effects of creatine in pregnancy, the usual advice is to avoid it if pregnant, or talk with your healthcare provider if you’re considering taking it.