Quick note: this post is taken from the Vitamin. Every Thursday, I drop some knowledge bombs on your face to help you reach your goals faster while avoiding all the bullshit.
There are a gazillion supplements on the market, all making wild claims and promises. Yet, I can count on one hand the supplements that actually work. Creatine is one of them. Among its many benefits, it can help you build muscle by allowing you to push harder in your workouts. But how much muscle could you gain if you took creatine? That’s what a new study looked at. 1
The what
This study was a systematic review and dose-response meta-analysis of randomised controlled trials (RCTs) looking at the effects of creatine supplementation on body composition. It also investigated whether dosage, type of exercise, alternative forms of creatine, age, and sex influenced the results.
The final analysis included 143 studies spanning a decade, with ~3,600 participants. 21 studies included females, 81 studies included males, and the remaining included both men and women. The quality of the included studies looking at body composition was rated as high.
What did they find?
Body weight: Creatine supplementation increased body mass by 0.86 kg (~1.9 lbs) compared to a placebo and muscle mass by 0.82 kg (~1.8 lbs).
Fat-free mass: Supplementing with creatine increased fat-free mass (FFM) by 0.82 kg/1.8 lbs, with the biggest effect seen in trained individuals (1.3 kg/2.9 lbs).
Body fat%: Creatine supplementation also led to a slight reduction in body fat percentage (-0.28%), though there weren’t any significant changes in body fat. This suggests that a decrease in body fat percentage is likely due to increases in muscle mass rather than reductions in body fat. In other words, if someone increases their body weight by gaining muscle but their body fat stays the same, the proportion of fat mass relative to body weight decreases. For example:
- Before Creatine Supplementation:
- Body weight: 70 kg
- Body fat: 14 kg
- Fat-free mass: 56 kg
- Body fat % = (14 kg / 70 kg) x 100 = 20%
- After Creatine Supplementation:
- Body weight: 72 kg (due to a 2 kg increase in FFM)
- Body fat: 14 kg (remains the same)
- Fat-free mass: 58 kg (increased by 2 kg)
- BF% = (14 kg / 72 kg) x 100 = ~19%
What type of creatine is best? Significant increases in muscle mass were only evident with creatine monohydrate when combined with resistance training or cardio and resistance training. While other forms of creatine showed similar effects to monohydrate, there isn’t enough evidence on newer forms to draw strong conclusions.
Age: Both younger (under 40) and older (over 40) individuals gained fat-free mass with creatine supplementation. Those under 40 gained an average of 0.89 kg/1.96 lbs, while participants over 40 gained an average of 0.87 kg/1.9 kg.
Sex: Both men and women gained fat-free mass but men showed a larger average increase of 1.2 kg/2.6 lbs, while women gained around 0.54 kg/1.2 lbs. While these differences weren’t statistically significant, women naturally have more creatine stored in their muscles, possibly due to their lower muscle mass relative to men, so they might not see as big an effect from creatine. That said, there’s a ton of evidence showing creatine can improve strength and power in trained and untrained females.
How much should you take? 5 grams of creatine/day is sufficient to significantly increase muscle mass. You can see this in the image below: While the positive trend suggests higher doses of creatine might be more effective for increasing FFM, the variability at higher doses indicates that further research is needed for doses higher than 5g/day.
What about loading? There wasn’t a huge difference between loading or just taking a maintenance dose. Loading increased FFM by 0.88 kg/1.9 lbs, while maintenance alone led to a gain of 0.72 kg/1.6 lbs. You might experience the benefits a bit faster by loading, but the differences level out over the long term.
But wait! There’s more
Another study published around the same time looked at the effects of creatine supplementation, specifically in a resistance-trained population, and found creatine increased FFM by ~1 kg, decreased body fat% by 0.9% and fat mass by ~0.7 kg. 2
The fat loss finding was notable since previous creatine research has primarily focused on FFM. The increased fat loss might be a side effect of creatine enhancing training performance, leading to an increase in energy expenditure, and indirectly from gaining muscle, which could raise metabolic rate.
Hold on, though
‘Fat-free mass’ isn’t just your muscles––it includes bone, water, and other tissues like your organs. Consequently, an increase in fat-free mass doesn’t necessarily mean an increase in muscle tissue.
To that end, Burke and colleagues conducted a meta-analysis that looked at direct measures of muscle mass and found that while creatine does have a positive effect, the size of that effect was pretty small. 3
When this study was published, I saw a lot of people take it as ‘proof’ that creatine is worthless. But is it? Much of this stems from a misunderstanding of how creatine works, bolstered by people’s unrealistic expectations of supplements.
Putting aside some of the study’s limitations (which the authors readily pointed out), creatine isn’t a muscle-building supplement; it’s a performance-enhancing supplement. You’re not magically going to gain muscle because you took creatine––it’ll allow you to train harder, which might result in muscle growth over time. If you’re expecting ‘steroid-like’ gains from creatine, well, that’s a you problem.
Also, does it really matter whether the gains from creatine are due to increased body water or actual muscle tissue growth? The end result still contributes to a more muscular appearance. Moreover, this water retention isn’t superficial–it helps signal the body to increase protein synthesis within muscle cells, which can contribute to muscle growth over time.
All said, unlike most supplements, creatine does precisely what it says on the tin. How much muscle you gain will depend on dozens of factors beyond creatine supplementation.
Bottom line
Creatine is still the MVP of (legal) performance supplements and it might help you build muscle and strength faster than if you weren’t using it. It’s also safe, even in high amounts (>30g/day), taken over several years (>5 years). 4
If you want to supplement with creatine, take 5g of creatine monohydrate daily. And keep taking it until you die.
Thanks for reading. If you enjoyed this, you’d love the Vitamin
95% of my new content is only sent to my email list. One email every Thursday, filled with actionable, evidence-based fitness advice to help you with your goals. If you enjoyed this, you’ll love my emails. You can learn more and subscribe for free here.