Creatine is not bad for your heart. The current body of evidence shows no harmful cardiovascular effects from standard creatine monohydrate supplementation in healthy people, and some research suggests it may actually support heart health. The International Society of Sports Nutrition has stated that creatine supplementation is safe across the lifespan and lists heart and vascular health among its potential benefits.
That said, a few edge cases and combinations deserve attention. Here’s what the research actually shows.
What Creatine Does in the Heart
Your heart is one of the most energy-demanding organs in your body, and it relies on a creatine-based energy system to fuel each contraction. Creatine helps shuttle high-energy molecules to cells that need them quickly, which is why cardiac muscle naturally contains significant creatine stores. Supplementing with creatine tops off these stores, and in theory, that should help rather than hurt.
An analysis of dietary creatine intake among 1,500 adults over age 65 found that 70% consumed less than the recommended amount (under 0.95 grams per day). Those with low creatine intake had a greater risk of angina, a type of chest pain caused by reduced blood flow to the heart, compared to people consuming more than 1 gram daily. This doesn’t prove creatine prevents heart disease, but it does suggest that having enough creatine on board is associated with better cardiovascular outcomes in older adults.
Effects on Blood Pressure
One of the more common concerns is whether creatine raises blood pressure. The available trial data is reassuring. In a randomized controlled trial of older men, the creatine group actually showed a nonsignificant drop in systolic blood pressure, from about 144 mmHg down to 136 mmHg, while the placebo and control groups stayed flat. That’s a trend in the right direction, not the wrong one.
No well-designed study has found that creatine monohydrate causes clinically meaningful increases in blood pressure. The mild water retention that occurs during the first week or so of supplementation (typically 1 to 3 pounds) is intracellular, meaning the water is pulled into muscle cells rather than increasing fluid volume in your bloodstream. This is a different mechanism than the sodium-driven water retention that contributes to high blood pressure.
The Atrial Fibrillation Question
There have been rare, anecdotal reports linking creatine to atrial fibrillation, an irregular heart rhythm. The most cited case involved a 30-year-old man with no prior heart problems who developed atrial fibrillation after starting creatine monohydrate. That case was published in 2005, and researchers flagged creatine as a possible trigger worth investigating.
It’s important to put this in context. A single case report, or even a handful of them, doesn’t establish a causal link. Atrial fibrillation occurs in young, otherwise healthy people for many reasons, and the timing with creatine use could be coincidental. No large-scale study has identified creatine as a risk factor for arrhythmias. Still, if you have a personal or family history of heart rhythm disorders, it’s worth mentioning creatine use to your cardiologist.
Creatine in Heart Failure Patients
Perhaps the strongest signal that creatine isn’t harmful to the heart comes from research on people whose hearts are already compromised. A 2025 systematic review in Heart, Lung and Circulation examined seven randomized controlled trials involving 243 patients with congestive heart failure who were given creatine supplements.
Short-term supplementation (eight weeks or less) improved muscle strength in three of the studies, with measurable increases in peak torque and endurance. One study found that patients walked nearly 50 meters farther in a six-minute walk test after creatine supplementation. Perceived exertion, or how hard exercise felt, decreased in another. Quality of life improved modestly in two studies.
Creatine didn’t improve ejection fraction (a measure of how well the heart pumps) or peak oxygen uptake in any of the trials. So it’s not fixing the underlying cardiac dysfunction. But the fact that it was safely given to heart failure patients, and helped them function better physically, strongly argues against the idea that creatine damages healthy hearts. The review’s authors noted creatine’s low cost, safety profile, and potential to improve functional independence as reasons it could be a useful add-on in heart failure rehab programs.
Combining Creatine With Caffeine
This is where things get more nuanced. If you take creatine alongside caffeine or pre-workout supplements containing stimulants, the combination can increase cardiovascular stress during intense exercise. A study on intermittent high-intensity sprints found that the creatine-plus-caffeine group had significantly higher heart rates than either the control group or the creatine-only group. Average heart rate hit 158 beats per minute with the combination, compared to 151 and 152 in the other groups. Blood lactate levels also climbed higher.
The elevated heart rate in this scenario is primarily driven by caffeine, not creatine. Creatine alone didn’t raise heart rate above the control group’s level. But if you’re stacking supplements before a hard workout, it’s the total cardiovascular load that matters. For most healthy people, a 6 to 7 bpm increase during sprints isn’t dangerous. For someone with an underlying heart condition or sensitivity to stimulants, it could be relevant.
Who Should Be Cautious
For the general population, creatine monohydrate at standard doses (3 to 5 grams per day) has no demonstrated cardiovascular risk. It’s one of the most studied supplements in sports nutrition, with decades of safety data behind it. The people who should pay closer attention are those with pre-existing heart rhythm disorders, since the rare case reports of atrial fibrillation, while not conclusive, haven’t been fully ruled out either. People with kidney disease should also exercise caution, not because of heart effects, but because creatine is processed through the kidneys.
If you’re taking creatine and notice palpitations, chest discomfort, or an unusually rapid heartbeat at rest, stop supplementing and get evaluated. These symptoms are uncommon with creatine use, but they’re worth taking seriously regardless of the cause.