Creatine supplements are popular among fitness enthusiasts. It's no wonder, with research showing it may help improve strength and power, and support recovery between workouts.
Given its many benefits, a team of researchers recently decided to investigate whether it could help people with long COVID. They specifically wanted to know whether creatine could help combat fatigue, which is one of the most common and debilitating long COVID symptoms.
The researchers from Serbia conducted a randomised controlled trial involving 12 people who'd had a recent long COVID diagnosis. This is the best study design to work out whether or not a treatment is effective.
Participants were randomly assigned to either receive a daily creatine supplement or a placebo (in this case inulin - a type of fibre). The treatment and placebo were an identical white powder that was mixed into water. This ensured neither the participants nor the researchers knew who'd received the creatine supplement until the trial was complete. The trial lasted over six months, ensuring the creatine had enough time to have an effect.
The researchers measured several outcomes - including how fatigued participants reported feeling and whether other long COVID symptoms (such as loss of smell) improved. The researchers also tracked how long participants could walk without feeling exhausted (an objective measure of fatigue), as well as levels of creatine in both muscle and brain tissues. This last outcome is important as it shows the supplement has made a measurable difference in the body - and shows participants adhered to the treatment.
Between 90-95% of participants took the supplement as directed for the duration of the study. Only one patient on creatine reported experiencing mild nausea.
After six months, the creatine group was shown to have higher concentrations of creatine in their muscles and brain tissue compared with the placebo group. But when the researchers looked at fatigue levels - both objective and self-reported - they found there was no difference between the placebo group and the creatine group.
However, the researchers did find that creatine may have some benefit when it comes to other long COVID symptoms (including loss of smell and taste, breathing difficulties, lung pain, body aches, headaches and trouble concentrating).
While all participants reported improvements in their long COVID symptoms by the end of the study, these improvements were greater in the creatine group. But it's worth noting that it's difficult to judge how severe these symptoms were to begin with or how great the improvements were as no information was provided on the scale the researchers used.
These results suggest that creatine appears to have had a positive effect on some self-reported long COVID symptoms. But creatine did not appear to have any effect on physical fatigue, which was a key focus of the trial.
The researchers suggest several potential mechanisms by which creatine could be causing these effects. One possible mechanism could be that it aids in adenosine triphosphate recycling in the brain and muscles. This molecule is important for energy production and release, and so creatine may make energy more available within these tissues.
Another potential mechanism could be that creatine changes nerve regulation by protecting the nerve cells and reducing nerve cell death, which might help brain symptoms. Creatine is also anti-inflammatory and has antioxidant effects, which may help prevent tissue damage - thereby preserving the function of the brain and muscle cells.
Need for research
This is the first study examining the use of creatine to treat symptoms of long COVID. The results are encouraging, and suggest it may be worth further exploration. But this is by no means enough evidence to warrant recommending this supplement to anyone who has long COVID.
Given the study used only a very few people, this means there's still a lot we don't know for certain when it comes to using creatine for long COVID symptoms - including whether sex differences affect a person's response to the supplement, if creatine works equally well in people of all ages and what effect a person's diet and exercise habits may have on how they respond to creatine.
Creatine is already shown to be safe and has minimal side-effects. It's also reasonably inexpensive and easy to take each day. Given there are still limited treatments for long COVID, this is certainly a worthwhile area to investigate further.
Future research will now need to focus on replicating these results in larger, more diverse groups, and understanding how creatine produces these effects. Researchers may also want to specifically look at people with low creatine levels, as evidence suggests people with long COVID have lower creatine levels - and this supplement could be of the most benefit to this group.
Author: Mary Hickson - Professor of Dietetics, University of Plymouth