Creatine is one of the few evidence-based (read: it works!) supplements, falling second perhaps only to trusty protein shakes.

For all its clear-cut benefits—from its availability to low cost to mixability to effectiveness—though, we might have missed out on a subtlety on the way we should be consuming creatine.

Now, just so we’re clear … no, it has nothing to do with dosage or timing.

But, instead, what we’re drinking it with.

More specifically: as it turns out, despite its incredible dissolvability in nearly everything, mixing creatine with our daily morning pick-me-up, caffeine, is a Very Bad Idea.

Why’s that so? And what should you do about it? Well, you know the drill—keep reading to find out!

What does creatine do?

First, though, here's a brief recap on what creatine is and what it could do for you:

Learn more about creatine supplementation (including the type of creatine to take, the best loading protocol to use, and potential side effects) here:

Is it a good idea to mix creatine with caffeine?

When it comes to creatine supplementation, timing doesn’t matter.

So long as you eventually saturate your muscles with creatine (typically achieved within 3 to 4 weeks regardless of loading protocol), you’re grand.

And this, unfortunately, played a role in our belief that we could mix creatine with anything—and still reap its benefits. Sadly, this is one belief research shows has been naïve and misguided all along.

The research in question: a recent 2021 paper published in the Journal of Dietary Supplements analyzed by Dr. Eric Trexler, a renowned sports nutrition researcher.

Dr. Eric selected 5 studies that studied the relationship between creatine, caffeine, and various resistance training outcomes (e.g., strength, endurance, body composition)—and found the following:

1. In 4 of the 5 studies, creatine alone worked to produce the desired training outcomes (i.e., improved strength and muscle growth) in participants.
2. However, the above performance benefits disappeared once researchers went ahead to mix creatine with an equivalent of 2 to 3 cups of coffee worth of caffeine (even though the participants’ muscle saturation levels of creatine were higher!)

Does that mean caffeine inhibits creatine?

Okay, so it’s a bad idea to mix creatine with caffeine—but why? What’s the explanation?

Here's the confusing bit: while there have been numerous proposed theories (from caffeine withdrawal to muscle relaxation time interference to caffeine's diuretic effects), none of them have any solid evidence.

Perhaps even more confusing, research also shows that caffeine ingestion neither alters creatine's pharmacokinetic properties nor its muscle saturation levels.

That said, several researchers have begun theorizing that the incompatibility of creatine with caffeine may not come down to any complicated chemical reactions—but, instead, it is simply a matter of gastrointestinal discomfort.

Promisingly, there are several studies supporting this hypothesis:

• 2005 study: 4 out of 10 participants who completed the study complained of gastrointestinal discomfort, which was notably more prevalent when they’d consumed caffeine and creatine together than the latter alone.
• 2013 study: 3 out of 7 participants in this study complained of a similar gastrointestinal discomfort when mixing creatine consumption with caffeine.

How to have your cake and eat it too

No matter the underlying mechanism, the truth remains that if you mix creatine with caffeine, you’ll likely fail to experience all its benefits. And what a shame that’ll be.

Then again, though, how do you choose between the two? It's almost like choosing between your mom and your significant other (unless you hate either or both of them, that is).

Don’t worry. Here are 3 suggestions:

Supplements belong to the top of the pyramid

After all this talk on creatine, caffeine, and performance-enhancing strategies, it’s probably important to remind you that you need to picture your fitness journey as something like Maslow's Hierarchy of Needs.

Training hard (and smart), eating well, and recovering adequately, form the foundations of your journey—while supplements are parked near the top.

Check out our past articles for more step-by-step guidance on the above:

You can’t use supplements to “hack” your way to the top.

So … if you’re still struggling to get the basics right, you might want to give GymStreak a shot. Just input your fitness goals, equipment availability, and ideal training frequency, and our smart AI-powered personal trainer app will do the rest.

You just need to show up and do your best. How about that?