Preface: This article is part three in a series on supplements reported to help sleep. In it, we take a look at whether these popular supplements have merits for helping sleep and what risks and downsides may come with them. Here are the previous articles on magnesium for sleep and kratom for sleep.
Glycine may be one of the most underrated supplements out there. Perhaps it’s because it’s not fancy, it’s not sexy, it doesn’t have the marketing potential to fly off the shelves the way a product called “super boost xxxplode pre-workout ” or whatever. The basics just don’t seem to sell as well, even though they work the best.
But glycine has a TON of research behind it, particularly with regards to improving sleep. to support in sleep.
On a chemical level, glycine is the simplest of all the amino acids. Partially because of its structural simplicity, it’s coined a “builder” of proteins. From collagens to more complex proteins glycine is a glue amino acid in almost all of them. There’s research on glycine to support everything from the immune system to muscle building to brain activity.
Because it’s a simple amino acid, it has a particularly low risk profile. Before bringing in bigger guns to improve sleep like kratom or melatonin, glycine is a low-risk supplement to add to your regiment.
Here’s a graph showing just how versatile a role glycine plays.
This brings us to the question we’re after today, which is how, and how much, can glycine improve sleep.
Because glycine is such a “glue” amino acid, one explanation is that it improves sleep because it improves our health and bodily function overall.
This is one part of the equation, but it does improve sleep in a few more targeted way as well.
Our body temperature rises and falls along with our circadian rhythms. During the daytime, we run the hottest and in the evening we hit our lowest point. In general, then, we want to sleep in a cool environment. For most people the ideal sleep temperature is between 60-68 degrees.
However, our modern environments discourage these natural temperature shifts. We often “run hot” well into the evening, which throws off our natural rhythm and damages our sleep quality. We discuss this phenomenon more in-depth in this article on how to fall asleep fast.
This is where glycine comes in. The best explanation for how glycine improves sleep is that it has a “hypothermic” cooling down effect on the body. Here is how one research study put it:
Of course, they go much deeper into how glycine does this. As far as we’re concerned, if you think temperature is one of the contributing factors to worsening your sleep quality, glycine can help solve this.
For example, if you live somewhere that’s hot and don’t pump the AC all the time, glycine can help you cool down. If you and your partner have disparate temperature needs that leaves you sweating at night, glycine can help you.
If you workout in the evening, glycine can bring down the temperature after training.
When you train, you increase your body temperature. It takes hours to come back down, and it’s one of the reasons why we can’t fall asleep within a few hours of training. So if you have to train in the evening, a glycine supplement right after can help cool your temperature back down.
Serotonin has numerous benefits which entire books have written about. It makes us happy, yes, but it also is a key component in the metabolic creation of melatonin. Simply, melatonin is the sleep hormone. It’s what allows us to get to sleep.
ince glycine increases serotonin, it initiates a cascade that leads to more melatonin and higher quality sleep. Many studies even use glycine on insomniacs, and reported elevated melatonin levels.
This brings us to what the best way to supplement glycine is. Since it’s a stable compound on its own (compared to magnesium, which needs to be bonded to other elements to form a stable compound), you can buy pure glycine.
This is the route I recommend because it’s the cheapest. Within this, you can buy glycine in both powder and capsule form. The powder form doesn’t taste great, but if you’ve ever had unflavored leucine or BCAAs, it’s not as bad at that. Nonetheless, if you get the powder, you’ll want to mix it in a smoothie or another drink.
The other option is to buy capsules. You can buy 1 gram capsules to take 3-5 a few hours before bed. If you’re used to taking supplements, this will fit seamlessly into your routine. It is a bit more expensive per gram in capsule form.If you want to be really savvy, you can take the powder and put them in capsules yourself.
Depending on your budget and work for your routine then, both powder and capsules are fine.
In the research, there’s no clear answer for this but anything you ingest in your stomach will take a bit of time. So I’d recommend 1-3 hours before bed, but don’t stress about it. Just take it sometime in the evening.