Can You Take Caffeine and Creatine Together? What the Research Says

In short: The idea that caffeine “cancels out” creatine mostly traces back to one small 1996 study of nine men. Newer reviews of around ten studies paint a more mixed picture: a coffee or caffeine dose before training after you’ve already built up your creatine stores doesn’t seem to cause problems, while taking caffeine every day during a high-dose creatine “loading” phase blunted creatine’s benefits in some (but not all) studies. The research is small and mostly in young men, so it’s worth keeping things in perspective.

Caffeine and creatine are two of the most popular supplements in gyms, and they often end up in the same pre-workout drink or morning routine. For years, though, a common piece of gym wisdom has been that you shouldn’t take them together. Here’s what the studies actually show.

What caffeine and creatine each do

Caffeine

Caffeine is a stimulant found in coffee, tea and energy drinks. The International Society of Sports Nutrition (ISSN), a scientific organization that publishes reviews of the research, concluded in 2021 that caffeine improves exercise performance in many (but not all) studies. The most consistent benefits are for endurance exercise, with smaller benefits for strength, sprinting and jumping. The doses studied are usually 3–6 mg per kilogram of body weight, taken about 60 minutes before exercise [1].

As one example, a small study of 14 people found that 250 mg of caffeine raised their maximal “anaerobic power” (the peak power you can produce in a short, all-out effort) compared with a placebo [2]. We cover caffeine’s performance effects in more detail in caffeine as an ergogenic aid.

Creatine

Creatine is a compound your body makes and that you also get from meat and fish. In muscle it’s stored as phosphocreatine, a quick-release energy reserve your muscles draw on during short, intense efforts like a heavy lift or a sprint. Supplementing tops up those stores. The ISSN’s position is that creatine consistently improves performance in short, high-intensity exercise, and that it has been safe and well tolerated in healthy people in studies of up to 30 g a day for five years [3]. For more on safety, see our post on long-term creatine supplementation.

Where the “don’t mix them” idea came from

The concern started with a 1996 study of just nine healthy men. For six days they took either a placebo, creatine alone, or creatine plus caffeine. The creatine dose was very high (0.5 g per kg of body weight a day, or about 35 g a day for a 70 kg person), and the caffeine dose was 5 mg per kg a day [4].

Both creatine groups had a similar small rise (4–6%) in the phosphocreatine stored in their muscles. But only the creatine-alone group performed better, producing 10–23% more torque (turning force) in a leg-extension test. The creatine-plus-caffeine group showed no improvement [4].

A follow-up study from the same lab, with 10 participants, offered one possible explanation. Creatine shortened muscle “relaxation time” (how quickly a muscle lets go after contracting) by about 5%, while three days of caffeine lengthened it by about 10%. The researchers suggested caffeine might override creatine’s effect [5]. Reviewers have also pointed to stomach upset from taking both at once as another possible factor [6].

What newer research shows

Since then, more studies have looked at the combination, and two systematic reviews (studies that gather and assess all the research on a question) have pulled them together.

A 2022 review of 10 studies found that when people loaded creatine first and then took a single dose of caffeine before exercise, three of four studies found no interference. When caffeine was taken every day during the creatine loading phase, results were split: two studies found caffeine interfered, three found no interaction, and one found the two worked better together. The authors concluded that creatine loading doesn’t seem to interfere with a one-off caffeine dose, but that daily caffeine during loading could interfere [7].

A separate 2021 review, also of 10 studies, came to a similar view. Taking caffeine about an hour before exercise after a creatine loading period gave an extra benefit over creatine alone in three of five studies. Daily caffeine during loading added a benefit in only one of five [8].

Two individual studies show what this looks like in practice:

• In a study of 12 physically active men, taking 6 mg/kg of caffeine after five days of creatine loading increased power in repeated cycling sprints compared with creatine alone [9].
• In a 2024 study of 24 healthy men, caffeine increased peak power in a 30-second all-out cycling test, while eight days of creatine didn’t. There was no sign that creatine got in the way of caffeine’s effect [10].

How strong is this evidence?

Not very strong either way. Most studies are small (often 9–24 people), short (days to a couple of weeks), done mostly in young men, and use high-dose creatine loading rather than the steady 3–5 g a day many people take long term. We don’t yet have good studies on whether your usual morning coffee affects long-term creatine use.

What this means in practice

This is general information, not personal advice, but based on the research so far:

• There’s little evidence that ordinary caffeine use wipes out creatine’s benefits. The clearest negative findings come from high-dose loading combined with daily caffeine.
• If you’re doing a loading phase, the research suggests it may be worth keeping caffeine moderate during those days. Skipping the loading phase is another option: around 3 g a day raises muscle creatine gradually over about four weeks, although any performance benefit may take longer to show [3].
• A caffeine dose before training after your creatine stores are already topped up looks fine and may even help [7][8][9].
• If taking them together upsets your stomach, spacing them out is an easy thing to try. Stomach discomfort has been suggested as one reason the combination sometimes performs worse [6].

Safety: how much caffeine is too much?

The US Food and Drug Administration (FDA) says most healthy adults can have up to 400 mg of caffeine a day, about two to three regular cups of coffee. Too much can cause a fast heart rate, anxiety, poor sleep, nausea and headaches. Pure or highly concentrated caffeine powders are especially risky: around 1,200 mg taken quickly can cause seizures, and that can be less than half a teaspoon of powder. If you’re pregnant, trying to get pregnant or breastfeeding, the FDA suggests talking to your health care provider about your caffeine intake [11].

In Australia and New Zealand, the Food Standards Australia New Zealand (FSANZ) board approved changes in April 2026 that would stop pure caffeine being sold as a food at retail. At that point the changes still had to pass a review by food ministers [12]. Pre-workouts and energy drinks can add up quickly too: some cans contain around 300 mg, as we explain in our post on caffeine and creatine in Bang Energy.

If you have a medical condition or take regular medication, check with your doctor before starting either supplement.

The bottom line on caffeine and creatine

The old advice to never mix caffeine and creatine was based on very limited research. Current evidence suggests the combination is generally fine, especially if caffeine is used before workouts once creatine stores are built up. There may be some interference when caffeine is taken daily during a high-dose loading phase. The studies are small, so expect this picture to keep changing as more research comes in.

This article is for general information only and isn’t medical advice. Talk to your doctor or another qualified health professional before starting a new supplement. See our medical disclaimer.

References

1. Guest NS, VanDusseldorp TA, Nelson MT, et al. International society of sports nutrition position stand: caffeine and exercise performance. Journal of the International Society of Sports Nutrition. 2021;18(1):1. doi: 10.1186/s12970-020-00383-4
2. Anselme F, Collomp K, Mercier B, Ahmaïdi S, Prefaut C. Caffeine increases maximal anaerobic power and blood lactate concentration. European Journal of Applied Physiology and Occupational Physiology. 1992;65(2):188-191. doi: 10.1007/BF00705079
3. Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition. 2017;14:18. doi: 10.1186/s12970-017-0173-z
4. Vandenberghe K, Gillis N, Van Leemputte M, Van Hecke P, Vanstapel F, Hespel P. Caffeine counteracts the ergogenic action of muscle creatine loading. Journal of Applied Physiology. 1996;80(2):452-457. doi: 10.1152/jappl.1996.80.2.452
5. Hespel P, Op’t Eijnde B, Van Leemputte M. Opposite actions of caffeine and creatine on muscle relaxation time in humans. Journal of Applied Physiology. 2002;92(2):513-518. doi: 10.1152/japplphysiol.00255.2001
6. Trexler ET, Smith-Ryan AE. Creatine and caffeine: considerations for concurrent supplementation. International Journal of Sport Nutrition and Exercise Metabolism. 2015;25(6):607-623. doi: 10.1123/ijsnem.2014-0193
7. Elosegui S, López-Seoane J, Martínez-Ferrán M, Pareja-Galeano H. Interaction between caffeine and creatine when used as concurrent ergogenic supplements: a systematic review. International Journal of Sport Nutrition and Exercise Metabolism. 2022;32(4):285-295. doi: 10.1123/ijsnem.2021-0262
8. Marinho AH, Gonçalves JS, Araújo PK, Lima-Silva AE, Ataide-Silva T, de Araujo GG. Effects of creatine and caffeine ingestion in combination on exercise performance: a systematic review. Critical Reviews in Food Science and Nutrition. 2023;63(20):4785-4798. doi: 10.1080/10408398.2021.2007470
9. Lee CL, Lin JC, Cheng CF. Effect of caffeine ingestion after creatine supplementation on intermittent high-intensity sprint performance. European Journal of Applied Physiology. 2011;111(8):1669-1677. doi: 10.1007/s00421-010-1792-0
10. Marinho AH, Silva-Cavalcante MD, Cristina-Souza G, et al. Caffeine, but not creatine, improves anaerobic power without altering anaerobic capacity in healthy men during a Wingate anaerobic test. International Journal of Sport Nutrition and Exercise Metabolism. 2024;34(3):137-144. doi: 10.1123/ijsnem.2023-0191
11. U.S. Food and Drug Administration. Spilling the Beans: How Much Caffeine is Too Much? FDA Consumer Updates.
12. Food Standards Australia New Zealand. FSANZ Board approves updated caffeine standards to support a safer food supply. April 1, 2026.