Creatine: One of the World’s Most Misunderstood Supplements

Walk into almost any gym or pick up any health literature and you may well hear about creatine. For some, it is the holy grail of strength training. For others, it’s a dangerous powder said to wreck kidneys, dehydrate athletes, or even cause baldness.

The truth—as usual—lies somewhere in between. Creatine is one of the most extensively researched supplements in medicine, and the evidence tells a surprisingly consistent story: creatine is both effective and safe when used properly, though not quite the panacea some claim.

Let’s step back, review the science, and unpack what creatine can and cannot do.

What exactly is creatine?

Creatine is a naturally occurring compound made in the liver, kidneys, and pancreas from three amino acids: glycine, arginine, and methionine. Humans typically produce about one gram per day, and we obtain another gram from animal-based foods such as meat and fish.

About 95% of our body’s creatine is stored in skeletal muscle. Skeletal muscles are those attached to the skeleton rather than smooth muscle such as gut muscles or the heart. There, it plays a crucial role in rapidly regenerating adenosine triphosphate (ATP)—the universal energy currency of cells. During short, explosive efforts (a sprint, a heavy lift, a jump), muscle phosphocreatine donates a phosphate group to ADP, instantly replenishing ATP (adenosine triphosphate) and keeping the muscle firing.

Supplementation expands the body’s creatine stores, allowing muscles to work harder for slightly longer. That small edge—accumulated over weeks of training—translates into measurable performance gains. This is the foundation of creatine’s scientific credibility.

What does creatine reliably do?

1. Improves strength and high-intensity performance

Decades of clinical trials show that creatine monohydrate improves performance in repeated bouts of high-intensity exercise. When paired with resistance training, it consistently increases gains in strength and lean muscle mass.

For athletes, this is not trivial: a few extra reps or slightly higher training intensity over months can translate into significant improvements. The International Society of Sports Nutrition calls creatine “the most effective legal performance aid currently available.”

2. Supports healthy aging

Muscle loss with age—sarcopenia—is a major driver of frailty, falls, and loss of independence. Resistance training is one cornerstone of prevention. Intriguingly, adding creatine seems to give older adults a modest but real advantage: greater gains in strength and muscle mass compared with training alone. It is not a substitute for exercise, but a helpful adjunct.

3. Enhances cognition under stress

The brain, like muscle, uses creatine as an energy buffer. Meta-analyses (good studies) suggest creatine supplementation can improve memory and reasoning, particularly in conditions where the brain is energy-stressed—such as sleep deprivation, vegetarian diets (which lower baseline creatine), or aging. In well-rested, young omnivores, the effect is inconsistent.

4. Improves glucose control in type 2 diabetes (with exercise)

A fascinating line of research shows that creatine can enhance the benefits of exercise on glucose metabolism. Randomised controlled trials demonstrate improved glycaemic control when creatine is combined with structured aerobic training. It is not a stand-alone treatment, but a potentially useful adjunct in motivated patients already exercising.

What are the common myths and misconceptions about creatine?

“Creatine dehydrates you and causes cramps.”

This has been thoroughly debunked. Multiple trials have shown no increase in cramps, no adverse effects on hydration, and no impairment of heat tolerance. In fact, creatine tends to increase intracellular water, which may be protective.

“Creatine causes hair loss.”

This claim traces back to a single small study in South African rugby players, which found that creatine supplementation increased dihydrotestosterone (DHT), a hormone linked to male-pattern baldness. But importantly, no hair loss was measured, and the result has not been consistently replicated. A more recent randomised trial found no effect on hair growth over 12 weeks. At present, the evidence linking creatine to hair loss is very weak.

“Creatine damages your kidneys.”

Here, nuance matters. Creatine supplementation does increase serum creatinine—a breakdown product used in estimating kidney function. But this rise usually reflects altered metabolism, not kidney damage. When kidney function is measured with more accurate markers (such as cystatin-C), creatine is not harmful in healthy individuals. In people with existing kidney disease, data are limited, so caution and monitoring are advisable.

“Creatine is a fat-loss aid.”

It isn’t. If anything, users often gain weight initially (0.5–1.5 kg), mostly from water and increased muscle mass. Any changes in fat mass come indirectly—because stronger training may allow greater calorie expenditure—not from creatine itself.

What are the areas of emerging but unproven interest?

• Depression: Small pilot studies suggest creatine may enhance antidepressant effects in women, but the evidence is far from conclusive.
• Traumatic brain injury: Preliminary studies—especially in children—hint at reduced symptoms and improved outcomes. Promising, but not yet established for clinical use.
• Neurodegenerative diseases: Interest is growing in Parkinson’s and ALS, but clinical trials so far have been disappointing.

In all these areas, creatine remains experimental rather than standard of care.

Is creatine safe and well tolerated?

Creatine has been studied in thousands of participants across hundreds of trials. The consensus: in healthy individuals, taken at recommended doses, it is safe.

• Kidney health: No evidence of harm in people with normal kidney function. Monitor more carefully in those with chronic kidney disease.
• General side effects: The most common issues are mild gastrointestinal upset (usually avoided by splitting doses) and early weight gain.
• Long-term use: Decades of use and follow-up studies remain reassuring.

Systematic reviews continue to place creatine among the safest supplements available.

Is creatine safe for teenagers?

The bulk of safety data comes from adults, but smaller adolescent studies in athletes (e.g. swimmers and American football players) have not shown harm.

Major medical bodies do not recommend creatine for casual use in under-18s, largely because of the lack of long-term paediatric data rather than evidence of danger.

Supervision matters: if a teenager is training seriously in sport and considering creatine, it should be discussed with a doctor, coach, and ideally a dietitian.

Bottom line: no signal of kidney, growth, or hormonal harm in teenagers has been demonstrated, but caution and medical oversight remain sensible.

GP top tip! If a teenager is using creatine, please be careful to ensure an inventory of other supplements is taken. There are some horrifying products available on the internet, that may have been purchased at the same time such as pre workout supplements with absurd levels of caffeine!

What are the practical guidelines for using creatine?

• Form: Creatine monohydrate is the reference standard—cheap, widely available, and effective. Other forms (e.g., creatine HCl, ethyl ester) are heavily marketed but not superior.
• Dosage:
  • Loading approach: 20 g/day (split into four 5 g doses) for 5–7 days, then 3–5 g/day.
  • Steady approach: 3–5 g/day from the outset (stores saturate after 3–4 weeks).
• Timing: Timing is not critical; consistency matters more. Taking with meals can improve tolerance.
• Hydration: Normal fluid intake is sufficient; creatine does not dehydrate.
• Caffeine: Early studies suggested a possible interaction, but the evidence is inconsistent. If both are well tolerated, there is no strong reason to avoid combining them.

Who benefits most from creatine?

Ideal candidates:

• Adults doing resistance or high-intensity training
• Older adults pursuing strength training as part of healthy aging
• Patients with type 2 diabetes who are exercising regularly

Use with caution:

• People with pre-existing kidney disease (monitoring recommended)
• Pregnant or breastfeeding women (safety data lacking)

The physician’s perspective

Creatine reliably improves performance in high-intensity exercise, supports gains in muscle and strength, and appears safe in healthy individuals. It may even have roles in aging, metabolism, and brain health—though the latter remain areas of active research.

What creatine is not, however, is magic. It won’t melt fat, cure depression, or prevent dementia. It is a tool—useful, well studied, and safe—best applied in the right context.

What’s the bottom line on creatine?

Creatine monohydrate is an effective well studied supplement. Its benefits in muscle performance are clear, its safety profile in healthy people is excellent, and its possible wider applications are intriguing but not yet conclusive.

For the health-conscious adult, the message is straightforward: if you are resistance training, if you are aging and want to preserve muscle, or if you are exercising to manage diabetes, creatine is worth considering.

Just keep it simple: monohydrate, 3–5 grams daily, with consistency and patience. Ignore the myths, the scare stories, and the overpriced alternatives. And remember: no supplement replaces a well-designed training programme, a balanced diet, and healthy living.

If you’d like to discuss whether creatine or other supplements are right for you, please book an appointment online here or call us on 0207 245 9333.