Can I Take Caffeine While Taking Creatine?

Performing at peak fitness levels is a goal for many athletes and gym-goers. And in order to meet the physical demands of high training loads, many will turn to supplements like creatine and caffeine to help boost strength and power through grueling workouts.

While the research on each of these performance-enhancing aids is abundant, there is far less information about taking these two supplements together. So, before you pop open the safety seal and take your first dose, there are a few things you should know before mixing creatine and caffeine.

Creatine and caffeine are both popular ergogenic substances in many athletic populations. While several supplements containing these two substances are available, you can also get creatine and caffeine from your diet. Many pre-workout supplements include both substances as main ingredients in one product, but you can also purchase each individually in higher doses.

The research is inconclusive on whether or not caffeine counteracts the effects of creatine, Andres Ayesta, MS, RD, LD, CSCS, CSSD, tells LIVESTRONG.com. "Some studies show there is a possibility of performance being affected by the co-consumption of both substances but results are mixed," he explains.

Read more: Does Caffeine Affect Muscle Growth?

A small, older February 2002 study published in the Journal of Applied Physiology showed that short-term caffeine intake for 3-days counteracts the benefits of creatine on muscle relaxation time. However, the researchers found that acute intake of caffeine, just 1 hour before exercise, did not affect muscle relaxation time.

Another small May 2016 study published in the Journal of Strength and Conditioning Research, found caffeine intake with creatine for five days did not negatively affect strength or sprint outcomes; however, it's important to note in this study that creatine alone did not see significant improvements in performance either. The article points out that creatine and caffeine do not display pharmacokinetic interactions when ingested together.

And although this study didn't show any benefit of adding caffeine to creatine, the authors mention previous studies which report performance improvements from mixing creatine in coffee or tea. Since many pre-workout supplement formulations include both creatine and caffeine, further research on potential interaction is needed.

Caffeine in moderate doses appears to be relatively safe. The U.S. Food and Drug Association (FDA) recommends a maximum dose of 400 milligrams a day as the best way to avoid negative side effects. Additionally, they cite 1,200 milligrams as a level that may produce toxic effects.

Like caffeine, there is a lot of research on the safety of creatine. The Mayo Clinic reports that for the most part, creatine is safe at the appropriate dose. But taken in large doses, it may have adverse side effects such as muscle cramping, nausea, dehydration, or dizziness.

Additionally, the Cleveland Clinic points out that combining oral creatine with other supplements may result in complications in the liver and kidneys. Additionally, it's important to maintain adequate hydration when supplementing with creatine and caffeine, especially since caffeine is a diuretic.

Read more: How to Use Creatine Most Effectively to See Lasting Results

In terms of creatine effectiveness, a July 2012 review study of creatine published in the Journal of International Society of Sports Nutrition found that supplementation with creatine has regularly shown to increase strength, fat-free mass, and muscle morphology with concurrent heavy resistance training more than resistance training alone.

And a March 2019 review published in the British Journal of Sports Medicine looked at eleven reviews, with a total of 21 meta-analyses, and found that caffeine ingestion improves exercise performance in a broad range of exercise tasks such as muscle endurance and muscular strength and anaerobic power and aerobic endurance. So, although their effectiveness together is questionable, they are effective on their own.