Creatine: the underrated supplement for muscle and brain as you age

More than a gym-bag supplement

Creatine has an image problem. To anyone who isn't following the research closely, it's still the powder bodybuilders and explosive-strength athletes use. That picture is out of date. In recent years, systematic reviews and meta-analyses have positioned creatine as one of the best-evidenced supplements for healthy aging — not despite age, but precisely because of it. Muscle preservation, recovery from exercise, and a specific set of cognitive functions all come up.

What the science shows: muscle

The clearest effect is still the oldest one: creatine combined with resistance training builds muscle mass and strength in older adults. A meta-analysis of 22 randomized trials in 721 participants aged 57 to 70 found, over periods of 7 to 52 weeks, an average extra gain of 1.37 kg of lean tissue mass compared with resistance training alone, with small but consistent additional effects on chest-press and leg-press strength and better performance on a sit-to-stand test — a direct measure of functional independence.

An important caveat from the same body of research: creatine amplifies a training stimulus, it doesn't replace one. A year of 1 g per day without training produced no change in muscle mass or function in the research. So it only works in combination with resistance work, never as a substitute for it.

What the science shows: brain

For cognition, the picture is more nuanced. A 2024/2025 systematic review and meta-analysis found significant improvement in three specific domains: memory (standardized effect 0.31), time needed for attention tasks (-0.31), and processing speed (-0.51) — with a striking age difference. Adults between 18 and 60 showed clear cognitive benefit; participants over 60 showed no measurable effect. The researchers suspect that age-related changes in how creatine crosses the blood–brain barrier play a role here. Overall cognitive function and executive function showed no significant improvement in either age group.

In short: for muscle, the age group above fifty is exactly where the effect is largest. For the brain, the window appears to sit between 18 and 60. Both findings are useful — but it isn't accurate to conflate them into "creatine helps your brain at any age."

Dosage: what's evidence-based

The International Society of Sports Nutrition (ISSN) remains the reference for dosing guidance:

• Maintenance dose: 3 to 5 g of creatine monohydrate per day, regardless of age.
• By body weight: as an alternative, 0.1 g/kg/day — for someone weighing 70 kg, that works out to roughly 7 g.
• Loading phase (optional): 20 g/day split into four doses for 5 to 7 days saturates muscle stores faster (within about a week versus roughly a month with the maintenance dose alone). The end result is identical, so skipping the loading phase isn't a missed opportunity — just a more patient path to the same place.

Safety — and the link to your blood values

In healthy adults, the ISSN reports no adverse effects at doses of 0.3–0.8 g/kg/day for periods of up to five years. One detail is worth explaining, not least because it connects directly to what we wrote earlier about biological age: creatine use raises blood creatinine levels. That isn't a sign of reduced kidney function — it's the result of more substrate being cleared through the kidneys. Anyone having blood drawn while using creatine should mention it; otherwise, an otherwise harmless rise in creatinine can be misread in exactly the kind of blood panel used to estimate biological age.

This safety data applies to healthy people. With diagnosed kidney disease, chronic kidney failure, or medication that affects kidney function (such as certain NSAIDs or diuretics), caution and a conversation with your doctor are warranted. There's no need to force fluid intake beyond normal drinking habits. The most common side effects are mild gastrointestinal complaints and, in a minority of users, muscle cramping.

How this fits into a coaching plan

Creatine isn't a miracle supplement and it doesn't replace resistance training, adequate protein, or enough sleep — it's a cheap, well-researched addition on top of a foundation that already needs to be solid. At HealthyDNA, we never look at it in isolation: whether creatine makes sense for you depends on your training structure (see also our articles on strength training for cyclists and training after 65), your current protein intake, and, if you have blood work done with us, your kidney function values as a baseline.

Wondering whether creatine would add anything to your own situation? Get in touch for a free intake conversation.

This article is general information and does not replace medical advice.

Sources: Frontiers in Nutrition (2025), "Creatine supplementation and exercise in aging: a narrative review of the muscle–brain axis"; Nutrition Reviews / Oxford Academic (2025), systematic review "Creatine and Cognition in Aging"; Frontiers in Nutrition (2024), meta-analysis "The effects of creatine supplementation on cognitive function in adults"; meta-analysis of 22 RCTs in older adults (57–70) on creatine, resistance training, and lean tissue mass; ISSN position on the safety and dosing of creatine supplementation.