Now and then, you don’t get enough sleep. When that happens once, it doesn’t affect you much. But while you might feel like the effects of back-to-back nights of poor sleep only accumulate to a point, the gloomy reality is that they continue to build. So, wouldn’t it be great if you could take something to help you minimise the results of insufficient sleep? Better yet, what if there was something that enabled you to perform better on less sleep? Some fascinating research suggests there just might be. Its name is creatine monohydrate. While there’s a lot to learn about creatine and sleep, today we’ll explore what we know to date.
- Creatine supplementation increases creatine stores in the brain.
- By reducing the accumulation of adenosine and adenosine triphosphate in the brain during wakefulness, creatine supplementation seems to reduce sleep depth, duration, and “rebound sleep” after sleep deprivation.
- Creatine supplementation also helps preserve cognitive and physical performance after sleep loss.
- Creatine has an array of other beneficial effects on brain function, sports performance, and most aspects of our biology.
- Creatine is very safe, and the most common side effect is a small increase in muscle mass. Best side effect ever.
- Taking 0.05 g powdered creatine monohydrate per kg bodyweight around breakfast is a smart option for most of us.
While many people know that creatine supplementation boosts creatine and phosphocreatine in skeletal muscles and thereby supports performance in brief, maximal efforts, few people realise that creatine and phosphocreatine also have important roles in the brain. Research over the last decade or so has shown that, by acting in the brain, creatine supplementation might well affect how much some animals sleep and how well people cope with insufficient sleep.
Might creatine reduce your need for sleep?
Before we try to answer this question, let’s consider how sleep is regulated. In much the same way that your body needs a certain amount of food, it requires sufficient sleep. Continuing this comparison, sleepiness is a bit like hunger: While you generally feel hungrier (sleepier) the longer it’s been since you last ate (slept), your hunger (sleepiness) doesn’t increase linearly over time but instead has peaks and troughs based on your habitual mealtimes (bedtimes).
Interestingly, sleep "hunger" doesn’t affect all stages of sleep equally. When you’re short on sleep, your increased sleep hunger leads you to gorge on the deepest stage of sleep (“slow-wave sleep”), and this sleep stage is particularly important to all sorts of housekeeping functions in your body, such as immune regulation.
The next paragraph gets a bit nerdy, so do skip it if you’re not interested in details.
The general increase in sleep hunger with ongoing wakefulness occurs because of a range of processes. However, much of it is driven by changes in signaling of adenosine and adenosine triphosphate (ATP) in the brain. Think of adenosine and ATP as chemical stopwatches that record how long you’ve been awake – the longer you’ve been awake, the more adenosine and ATP accumulate in the narrow spaces around the cells in your brain. Adenosine and ATP then activate (“agonise”) receptors on certain brain cells (glial cells), leading to release of small, sleep-promoting proteins named cytokines (interleukin 1 and tumor necrosis factor, specifically). These cytokines then affect the movement of neurotransmitter receptors on neurons, and the combination of these movements makes the neurons less likely to “fire”. When this happens in many nearby cells, this local network of neurons starts showing sleep-like activity. Eventually, synchronisation of such sleep-like activity between adjacent neuronal networks leads to sleep in larger brain structures. So, high activity in one part of the brain ultimately promotes sleep in the region, and what we all refer to as sleep is what happens when this regional sleep happens in much of the brain at once.
The relevance of creatine is that supplementing with creatine monohydrate can slightly increase the total amount of high-energy phosphates in the brain, which in turn can buffer the accumulation of adenosine and ATP between brain cells during wakefulness. This should reduce sleep hunger, which would be expected to shorten sleep and reduce time spent in deep sleep. Sure enough, this is exactly what a study of rats showed. After the researchers added creatine monohydrate to the animals’ chow for 4 weeks, the rats:
- Had a trend to more phosphocreatine in brain regions important to sleep
- Had less ATP in some brain areas
- Slept 32% less, which was driven by less deep sleep
- Had less “rebound” sleep after sleep deprivation
This is fascinating, but humans aren’t rats. An important difference between us and our rodent counterparts is that creatine supplementation probably increases brain creatine more in them (about 30% in rats) than in us (5 to 10% in humans). My guess is this means that creatine supplementation affects sleep more in rats than humans. This said, I’ve been in touch with one of the researchers of the study discussed above, and I know that they’ve since done a study of humans and found similar results, including that creatine reduced sleep duration. I’ve been told the research will be published soon.
What’s especially remarkable that if creatine reduces sleep duration and depth, you might expect it to negatively affect health and performance. The reason is that sleep loss usually negatively affects all aspects of our biology – it compromises the function of the brain, cardiovascular system, endocrine system, reproductive system (in both women and men), immune system, digestive system, and musculoskeletal system. However, creatine supplementation actually improves the function of most of these systems.
Might creatine help you cope with sleep loss too?
I’ve previously blogged about how caffeine antagonises adenosine receptors and thereby helps maintain performance after sleep loss. Well, by influencing adenosine signaling in different ways, creatine seems to have some similar, positive effects:
- 1 week of high-dose creatine supplementation (4 x 5 g per day) reduced the degree to which sleep deprivation worsened reaction time, balance, and mood.
- The same scientists found that 1 week of high-dose creatine supplementation (4 x 5 g per day) supported performance in a test of brain function completed several times during 36 h of sleep deprivation.
- After elite rugby players had a night of limited sleep, a single dose of creatine (0.05 to 0.1 g per kg bodyweight) prevented a decline in performance in a sport-specific, passing test.
These results are interesting, encouraging, and are also consistent with many other studies showing positive effects of creatine on measures of memory and reasoning ability, particularly when the brain is under duress.
But is creatine safe?
Creatine is one of the best-studied supplements out there, and most of us already consume multiple grams of it each day in our regular diets. Long-term creatine supplementation seems safe – even doses of up to 30 g for 5 years. There don’t seem to be withdrawal effects when people stop taking it – their creatine stores just eventually return to pre-supplementation levels.
The most common side effect is a small increase in bodyweight. However, this is a good thing, for it reflects an increase in skeletal muscle mass. This increase in mass can deter some people (e.g., people who are overly focused on bodyweight, some endurance athletes, and some weight-category athletes), but it generally shouldn’t, for muscle mass is critical to longevity.
Beyond very rare instances in which someone must stay below a certain weight, perhaps the only people who should think twice about creatine supplementation are people who have dysfunctional kidneys. This group includes those with chronic kidney disease, and blood pressure- or diabetes-related kidney problems.
Tangentially, supplementation with a precursor to creatine named guanidinoacetic acid (GAA) might more potently boost brain and muscle creatine stores than creatine supplementation. This might be because GAA can enter the brain via more routes than creatine, which mostly enters the brain via one transporter (Solute Carrier Family 6 Member 8, in case you're curious). But while GAA is an intriguing supplement, we don’t know that much about its safety, and GAA seems to have some undesirable side effects, such as increasing homocysteine, which associates with increased risk of cardiovascular problems.
How to take creatine monohydrate
If you want to saturate your body’s creatine stores ASAP, use a “loading phase” in which you take 5 g creatine 4 times a day for 5 to 7 days before switching to a maintenance dose. (Don't take much more than 5 g at once, for you might experience digestive issues.) However, this isn't necessary, so simply take the maintenance dose (about 0.05 g creatine per kg bodyweight per day) every day. This will eventually saturate your muscle creatine stores too – you’ll just take a bit longer to fill your stores.
One thing I'll add is that we really don't know the best way to boost creatine in the brain. Different parts of the brain have different creatine contents, and there's also substantial variation in brain creatine between people. It seems plausible that boosting brain creatine might require higher doses than those needed to increase muscle creatine, but this is speculative. Basically, we need studies that measure how different doses of creatine affect creatine contents of different parts of the brain in different populations.
Next, there’s large variation between people in how they respond to creatine. For example, some seem to be “non responders” to creatine, meaning that supplementation has little effect on their creatine stores, performance, and health. However, these people are clearly in a small minority. At the other end of the spectrum, it’s plausible that people on “plant-based” diets might experience particularly large benefits from creatine supplementation. The reason is that animal foods such as fish and meat tend to be much higher in creatine than plant ones, so vegans and vegetarians tend to have lower creatine intakes than omnivores.
There hasn’t been much research on what time of day it’s best to take creatine, but it usually makes sense to take it at the start of your day. If nothing else, you’re probably more likely to remember it that way. As protein and carbohydrate intake can increase creatine uptake, take it around the same time as breakfast.
Regarding which creatine supplements are best, go for creatine monohydrate. If in doubt, go for Creapure® creatine, although I’ll add that the purity of many other creatine products is at least as good as Creapure®.
Do NOT buy ready-to-drink product containing creatine - when creatine is added to a liquid, it soon starts slowly degrading to creatinine, which doesn’t share creatine’s advantageous effects.
Since I first began writing about nutrition about 15 years ago, I’ve held that creatine is about the most useful supplement there is. I stand by this position, and at some point we’ll circle back to just how widespread the positive effects of creatine supplementation are.