What We Know About the Link Between Creatine and Anxiety

If you take creatine to get gains at the gym, do you also get anxiety? If you're taking or considering the supplement, you may have heard that creatine can cause anxiety or mood swings — or even help with them.

But research is mixed when it comes to mental side effects of creatine monohydrate. Creatine has not been proven to directly cause anxiety, but more research is needed to fully understand its effects on anxiety.

Here's what we know so far.

Creatine supplements are commonly used to boost athletic performance and strength, according to the U.S. National Library of Medicine (NLM).

But, beyond its potential power boost, "there's some indication that creatine could increase anxiety," says Lynn Bufka, PhD, associate executive director of Practice Research and Policy at the American Psychological Association.

But, Bufka says: "in terms of its impact on mental health and brain function, there's not a lot of research out there, and what there is, is pretty basic."

To date, research largely focuses on the supplement as a monohydrate and its role in performance enhancement, as noted in a June 2017 study in Journal of the International Society of Sports Nutrition, not its role in anxiety.

"There are a few studies that suggest creatine supplementation can improve mental performance in people who are sleep-deprived," says registered dietitian Lona Sandon, PhD, RDN, an associate professor in the department of clinical nutrition at the University of Texas Southwestern Medical Center at Dallas, "which is often the case in those with anxiety."

It may also be that creatine levels in the brain are lower among people suffering from anxiety disorders, she says, "due to dysfunction of the ability to metabolize creatine."

But supplements wouldn't necessarily solve that problem, Sandon says. And, like Bufka, she cautions that when assessing creatine's effect on anxiety, "the limited research leaves us with limited answers."

Nevertheless, a September 2019 review in ‌Biomolecules‌ suggests creatine might have an antidepressant and mood-improving effect. It notes most trials to date, though small, have shown positive effects of creatine on major depressive disorder. Larger studies are needed to confirm these effects.

That could be relevant, given depression and anxiety are part of the same family of mental health conditions, according to a May 2020 study in the ‌American Journal of Psychiatry‌, which notes nearly 46 percent of people with a history of major depression also have a history of one or more anxiety disorders.

However, an earlier May 2012 study review in ‌Neuroscience & Biobehavioral Review‌s (‌NBR‌) had turned up contradictory findings on creatine's effect on both depression and anxiety.

One study in the ‌NBR‌ review suggested creatine may elevate mood disorders among vulnerable people, linking just a week of supplements (at 25 grams per day) to increased nervousness and aggression.

But other research cited by the ‌NBR‌ report found creatine might help post-traumatic stress disorder (PTSD).

Beyond the link between creatine, anxiety and mental health, when it comes to its safety, the good news is, "creatine supplementation is safe in most people," Sandon says — a take seconded by the Cleveland Clinic.

The NLM describes creatine as likely safe when taken in oral doses up to 25 grams per day for two weeks, or 4 to 5 grams per day for up to 18 months, noting that some research suggests it's possibly safe at 10 grams daily for up to five years.

While generally safe, daily creatine has been linked to GI problems and other side effects, per the ‌NBR‌ study, including:

• Diarrhea or loose stools
• Nausea
• Vomiting
• Abdominal pain
• Increased or decreased appetite
• Weight gain

Creatine may also worsen kidney problems among those who already have kidney disease.

Ultimately, no matter your condition or age, you should talk to your doctor before taking creatine, per the Cleveland Clinic.