For decades, it has been a staple of gym routines – a supplement that helps build muscle and improves sporting performance.
Creatine burst in to public consciousness after Linford Christie credited it with giving him the edge he needed to win gold at the Barcelona Olympics in 1992, aged 32 – unusually old for a 100m champion.
Since then, it has been an essential bit of kit for athletes and those who aspire to them. But now, something unexpected is happening.
In recent years, scientists have begun to look at the decidedly unglamorous, cheap powder in a very different way – not as something for the already fit, but as a potential support for a group usually far removed from that world: midlife women.
Indeed, striking early research suggests it may help ease depression, improve sleep, boost bone health and potentially even ward off dementia in this group.
Such is the excitement that Professor Sophie Scott, director of the Institute of Cognitive Neuroscience at University College London, says many of her colleagues are now 'evangelical' about its potential.
'There is evidence that it can help with cognition, attention and information processing speed,' she says.
It is a remarkable shift – but mounting evidence suggests its sporting benefits may only be part of the story.
Linford Christie won gold at the Barcelona Olympics in 1992 and was part of the GB team who were the first to use creatine to enhance performance
Creatine supplements come in many forms, including as powders and tablets, with doses up to 20g - which from diet alone would equate to one kilo of meat
And it's not just brain experts who are taking notice.
Dr Fozia Ahmed, a consultant cardiologist at Manchester University NHS Foundation Trust, says the supplement is all the rage in her department because of evidence it may help protect against heart disease.
She says this is because creatine 'enhances the strength and performance' of the heart. So, what is creatine – and should you be taking it?
A naturally occurring compound, creatine is found in protein-rich foods such as meat and fish. The body also produces it.
Experts say the key to understanding its importance is a molecule called adenosine triphosphate, or ATP.
ATP is essentially the body's energy source, powering everything from muscle movement to digestion.
During intense activity, the body can briefly run low in ATP, leading to fatigue.
But creatine, experts say, can boost ATP levels – giving the body an extra burst of energy.
It is this boost that makes creatine so useful for athletes, allowing them to work out for longer.
An analysis last year of 61 studies found that taking a creatine supplement increased muscle growth in gym-goers by up to 50 per cent compared with a placebo.
However, increasingly, studies suggest that boosting ATP levels may have wide-ranging – potentially even lifesaving – benefits for the body.
A 2024 review of 16 studies found that a daily creatine supplement can improve memory, attention and processing speed.
Experts believe that women may benefit more than men from creatine supplementation.
This is partly because studies show that women on average consume fewer animal products, which are rich in creatine.
One 2017 study found that taking 5g of creatine daily helped women sleep for longer.
Another study found that women who took 5g of creatine alongside antidepressants were less likely to experience symptoms of depression than those taking the drugs alone.
But perhaps some of the most compelling benefits are seen in older women.
Experts say the supplement could help fend off osteoporosis – the bone-thinning disease that affects around half of women over the age of 50.
Research shows that increasing muscle mass can help prevent life-changing fractures in osteoporosis patients by reducing the risk of serious falls.
A 2017 review, which included 22 studies in people aged 57 to 70 taking creatine, found the supplement improved muscle mass by 1.4kg and led to a small increase in strength.
Researchers are now even investigating whether creatine could help prevent dementia.
Last year a small, preliminary study found Alzheimer's patients given an 8g daily dose of creatine performed better on cognitive tests than they had before taking it.
Professor Sophie Scott, director of the Institute of Cognitive Neuroscience, a world-leading brain health research centre at University College London, says many of her colleagues are 'evangelical' about creatine
Meanwhile, a 2023 review of eight studies found creatine improved memory in healthy people, with greater effects seen in older adults aged 66 to 76.
Experts also say it could benefit heart health, potentially lowering the risk of life-threatening complications.
'Creatine enhances strength and performance by increasing the availability of ATP, which is essential for heart function,' says Dr Ahmed.
'It fuels the constant contractions required to pump blood.'
However, experts disagree over how much creatine people should take.
Research suggests the body uses between 1g and 3g of creatine a day, while most brands recommend between 3g and 5g.
Some advocate a 'loading phase', involving doses of up to 25g a day – but most experts say this is unnecessary.
'The belief that larger doses yield greater benefits is unfounded,' says Dr Mehdi Boroujerdi, a pharmaceutical researcher.
'Excess creatine is simply excreted as creatinine, offering no additional advantage.'
In the past, doctors warned that creatine could cause side effects such as kidney damage.
However, experts say evidence now suggests that, for healthy people, the risks are low.
'While not a panacea, creatine is a supplement with significant potential,' concludes Dr Boroujerdi.