Research review
Does creatine affect the heart? What the research does and doesn't show
One published case report describes a young man's irregular heartbeat after taking creatine, alongside using it. Small controlled trials, including one in people with existing heart failure and one in healthy older men, haven't reproduced that finding, though none of them were designed to catch a rare event.
The evidence doesn't support creatine as a cause of heart attacks or a dangerous heartbeat, and it isn't a treatment for heart disease either. A single published case report ties one young man's irregular heartbeat to creatine use; controlled trials, including one in people with existing heart failure, haven't reproduced that finding, though none were built to catch a rare event.
What the evidence doesn't support
It doesn't support a causal link between creatine and a heart attack, and it doesn't support creatine as something that treats or reverses heart disease once it's present. The main piece of evidence pointing toward a risk is a single case report — one patient, not a trial — and the main body of evidence pointing toward safety is a handful of small, short controlled trials that weren't designed to detect a rare cardiac event even if one existed. Both facts can be true at once, and neither adds up to a confident answer either way.
What the trials found
The case for concern is a single published report: a 30-year-old man with no prior cardiac history came to an emergency department with an irregular heartbeat (atrial fibrillation with a fast ventricular rate). Standard tests for other causes — thyroid levels, electrolytes, a drug screen, alcohol use — came back negative. When asked about supplements, he reported taking creatine. He was treated with standard heart-rhythm medication and discharged within a day. The report's author notes earlier anecdotal reports of a similar pattern, but a single case cannot show that creatine caused the arrhythmia rather than simply preceding it by coincidence — that distinction requires a controlled trial, and none exists for this specific outcome.
The controlled evidence available doesn't point toward a cardiac safety problem, though it's testing different things. A 7-day trial in men aged 55-80 given 20 g/day of creatine tracked several heart function measures — stroke volume, contractility, ejection fraction — and found no adverse change in any of them versus placebo or an untreated group.
Two small, older trials went further and tested creatine directly in people who already had heart failure, on top of their usual medication. In one, 17 patients with reduced heart pumping capacity took 20 g/day of creatine for 10 days; muscle energy stores and several exercise performance measures rose more than with placebo, but the heart's own pumping capacity (ejection fraction) didn't change. In the other, 20 heart failure patients (13 completed) took the same dose for 6 weeks in a crossover design; body weight and muscle strength rose with creatine, but exercise capacity, walking distance, ejection fraction and quality-of-life scores showed no difference from placebo. Neither trial reported a new arrhythmia or other cardiac safety event, but neither was designed with a safety endpoint like that as its focus, and both are decades old with small sample sizes.
A more recent review of creatine and heart failure sums up where this leaves things: energy stores in a struggling heart are measurably lower, small trials have tested whether replacing that energy with creatine changes anything, and the results so far are mixed and inconclusive — not evidence that creatine is a heart failure treatment, and not evidence that it's dangerous for that group either.
Questions people ask
Can creatine cause heart palpitations?
One published case report describes a young man who developed an irregular heartbeat while using creatine, with no other cause identified. That's a single case, not a trial, so it doesn't establish that creatine caused it — but it's the specific piece of evidence behind this question, and it's fair to know it exists.
Can creatine cause a heart attack?
We didn't find a published case report or trial reporting a heart attack linked to creatine use. The one cardiac case report that exists describes an irregular heartbeat, not a heart attack, in a single patient.
Is creatine safe for the heart?
The controlled trials that measured heart function directly — including one in people with existing heart failure — didn't find a negative signal. None of them were large enough or built specifically to catch a rare event, so this is a "no signal in the trials we have," not a guarantee.
Does creatine help heart failure?
Small trials added creatine to standard heart failure treatment and found it raised muscle strength and exercise measures without changing how well the heart itself pumps. A review of this research area calls the results mixed and inconclusive — not an established use, and not something to try instead of prescribed treatment.
When to talk to a doctor
An irregular heartbeat, chest pain, or any new cardiac symptom is a reason to see a doctor promptly, whether or not you take creatine. If you have diagnosed heart disease or heart failure, or take heart medication, talk to your doctor before adding creatine — the trials above studied it as an add-on under medical supervision, not as something to start on your own. Creatine is not a treatment for heart disease, and stopping a prescribed heart medication in favor of a supplement is never something this page supports.
Related reading: creatine and blood pressure: what the research does and doesn't show, creatine side effects, and creatine interactions.
Sources
- Lone atrial fibrillation associated with creatine monohydrate supplementation A single case report describes a young man who developed an irregular heartbeat while using creatine, with no other identified cause found — a single case that cannot show creatine caused it, only that the two occurred together once.
- Effects of acute creatine supplementation on cardiac and vascular responses in older men; a randomized controlled trial A 7-day trial in older men found one measure of vascular stiffness changed significantly with creatine, and blood pressure moved lower on one side without reaching statistical significance, while several other cardiac measures showed no difference — a small trial with an age mismatch between its groups.
- Creatine supplementation in chronic heart failure increases skeletal muscle creatine phosphate and muscle performance A 10-day trial in heart failure patients found creatine, added to standard treatment, raised muscle energy stores and exercise performance measures without changing the heart's own pumping capacity (ejection fraction).
- Creatine supplementation improves muscle strength in patients with congestive heart failure A 6-week trial in heart failure patients found creatine, added to standard treatment, raised body weight and muscle strength without changing exercise capacity, walking distance, heart pumping function or quality of life.
- Creatine deficiency and heart failure A review of the heart failure literature found creatine energy stores are lower in a failing heart, but that testing creatine supplementation as an add-on to standard treatment has produced small, mixed, inconclusive trials, not an established benefit.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.