Glycine for Sleep: How and Why This Amino Acid Supports Restorative Sleep

Getting quality sleep every night is crucial for your brain and body to rest and repair. Neglecting sleep wreaks havoc on every aspect of your mental and physical health. Sure, you might be able to push through for a while, but eventually, you’ll be running on empty. In fact, research shows that lack of sleep leads to poor mental health, cardiovascular disease, weight gain, and even chronic pain.

I’ve seen it myself. I used to be a night owl, waiting until after dark to do most of my work and admin. It wasn’t long before my motivation, physical performance, and overall well-being took a nosedive.

Thankfully, I totally re-shaped my sleep routines, including finding a supplement protocol that works for me. This included glycine, which calms the nervous system when taken before bed.

Nowadays, I fall asleep faster, get better quality Zzz’s, and wake up refreshed and alert. If you’re also struggling to catch some shut-eye, glycine might be a part of an all-encompassing sleep hygiene makeover.

Today, we’ll explore what the research says about the benefits of glycine for sleep and how it works. We’ll also discuss the health benefits you can expect when adding this amino acid to your routine.

If you’re only looking for a list of the best glycine supplements, head straight here. However, if you want to learn more about glycine for sleep, stick around as we get to grips with this sleep-promoting compound.

What is Glycine?

Glycine is one of the 20 amino acids that your body uses to build tissues, DNA, hormones, brain chemicals, enzymes, antioxidant compounds, and other substances. It’s a non-essential amino acid, which basically means your body makes it in-house.

Glycine is also essential to form collagen, a flexible protein in your muscles, tendons, ligaments, skin, and bones. In addition to its structural role, glycine supports the nervous system. It acts as an inhibitory neurotransmitter that calms down excitable neurons in your brain. This makes it a soothing and relaxing amino acid that helps you sleep better. However, most people are not aware of its sleep-promoting properties.

Increasing your glycine intake could be a game-changer for your sleep. It’s non-habit-forming, generally free of side effects, and available over the counter.

Glycine for Sleep: How Does it Work?

While scientists still have a lot to learn about glycine and sleep, emerging research suggests it works in a few different ways.

As mentioned earlier, glycine is a chill amino acid. It helps you release a neurotransmitter called GABA to calm the central nervous system. GABA reduces nervous system overstimulation, letting you drift off into restful sleep. But that’s not the only way glycine helps you catch Zzz’s.

Your brain has an internal 24-hour timer called the circadian rhythm located in the suprachiasmatic nucleus. I know it sounds science-y, but basically, it’s like a fancy watch that tells other regions to regulate your sleep, appetite, hormones, and enzymes. Glycine runs things from backstage by interacting with the NMDA receptors in the suprachiasmatic nucleus (1).

Researchers have also found glycine can boost your serotonin levels, which influences your mood, motivation, and sleep. As a bonus, serotonin is also a precursor to melatonin, the sleepy hormone that helps you drift off. Interestingly, people with lower serotonin levels are more likely to have poor-quality sleep and insomnia (2). Serotonin synthesis may be another way glycine can help you sleep better.

But wait, there’s more! Taking glycine before bed can even help you cool down. When you snooze, your core body temperature naturally drops, but glycine can speed up the process by increasing blood flow to your skin (3). This signals your brain to start producing melatonin, which helps you get to sleep faster.

Does Glycine Really Work for Sleep?

A lot of people seem to think so. That said, anecdotes don’t hold much weight in the scientific world. Fortunately, studies using human volunteers show glycine is a well-tolerated supplement that may improve your overall quality of sleep.

Glycine can help you fall asleep faster by shortening sleep onset latency, an indicator of good sleep. Essentially it means less time tossing and turning and more time snoozing peacefully. Best of all, the faster you fall asleep, the more time you spend cycling through all the different stages of sleep.

Research on animals has shown that glycine can increase the time you spend in REM sleep – the stage of sleep when you’re dreaming.

Plus, a 2016 study on humans found those who took 3 grams of glycine reported better sleep quality and efficiency (the time spent in bed versus time spent sleeping). Polysomnographic changes (seen on fancy machines that measure brain waves) also showed they fell asleep faster and got more slow-wave sleep – the stage of deep sleep when your body does most of its healing and recovering. It’s so important to get enough of this kind of sleep if you want to wake up feeling refreshed. As the cherry on top, those who took glycine reported feeling less sleepy during the day and performed better on cognitive tests.

Benefits of Using Glycine for Sleep

Improving your sleep game with glycine can level up your health. Pretty much every health marker improves when you get more Zzz’s.

Here are some key benefits you can expect when you start taking glycine for sleep.

More Energy

Using glycine to get better sleep can help you feel more energetic during the day. This study found glycine ingestion before bed improved sleep quality, leading to less fatigue and greater well-being the next day.

Plus, glycine helps your body produce creatine, which means more energy for your muscle and brain cells. This may also explain why a placebo-controlled study found 3 grams of glycine before bed significantly reduced fatigue and daytime sleepiness from acute sleep restriction.

Improved Mental Performance

If you’re struggling with focus due to poor sleep patterns, jet lag, or working night shifts, glycine could be a game-changer for your mental performance during the day. Research suggests it is a cognitive enhancer by improving episodic memory and attention. 

However, to really improve your cognition and focus, check out The Best Nootropic Supplements.

May Support Jet Lag Recovery

Glycine is worth a try if you want to get back on a regular sleeping schedule after traveling or working night shifts. By regulating your sleep cycles, it can help get you back to feeling like your old self again.

Better Gains at the Gym

As any bodybuilder or gym enthusiast knows, a great physique relies on a good recovery strategy.

When you sleep, the pituitary gland in the brain releases human growth hormone (HGH) for cellular repair, muscle recovery, muscle growth, and fat burning. So, improving your sleep with glycine may help you get better results at the gym.

Fewer Trips to the Bathroom at Night

If you’re constantly waking up to use the bathroom at night, glycine might help with that too. This study found 3 grams of glycine before bed reduced nighttime urinary urgency and frequency. Plus, it reduced sleep latency as well as nighttime blood pressure.

FAQs about Glycine for Sleep

What is the Best Way to Take Glycine for Sleep?

Taking glycine for better sleep is pretty simple; it’s available in capsule and powder form.

Most studies recommend taking 3-5 grams of glycine per day. For best results, take it on an empty stomach about an hour before bed. However, everyone’s different, so always discuss the dose with your healthcare provider before you start supplementing.

Can I Take Glycine Every Night?

You can take glycine every night, provided you follow the recommended dosage. In fact, consistency is key for regulating your sleep-wake cycle and improving the quality of your sleep.

Is Glycine Safe?

Glycine is a natural amino acid that’s safe to take at the recommended dose. Research has found no risks associated with taking up to 90 grams of glycine, although we don’t recommend taking such a high dose! 3-5 grams per day is plenty if you want to use it for better sleep.

Is Glycine Addictive?

Glycine is a natural, non-habit-forming sleep aid. Unlike prescription sleep medications, you won’t experience withdrawal symptoms if you miss any doses of glycine. Plus, it doesn’t leave you feeling like a zombie the next day.

Can I Get Glycine from Food?

Absolutely! You can find glycine in pork, chicken, beef, fish, eggs, dairy, spinach, kale, cabbage, nuts, seeds, and legumes. However, the best sources of glycine are gelatinous cuts of meat and slow-cooked broths made with bones, tendons, ligaments, and other connective tissues. Unfortunately, these foods aren’t common in the standard American diet. Moreover, vegetarians and vegans might not be getting enough of this nutrient.

Personally, I love to drink bone broth between meals. I also make simple “gummies” with fruit juice and gelatin. They’re packed with glycine and make a great bedtime snack. If that’s not your cup of tea, supplements are a reliable option for better sleep.

Does Glycine Have Side Effects?

The amino acid glycine is very safe with a relatively low risk of side effects – most people tolerate it well. However, there are people who experience mild digestive discomfort, while others report vivid dreaming.

To minimize the risk of side effects, start with a low dose and increase it gradually. In addition, follow the recommended dosage and timing instructions on your glycine supplement.

Remember, it’s best to consult your healthcare provider before trying a new supplement, especially if you’re taking any medication or are pregnant or breastfeeding.

Does Glycine Interact with Medications?

Glycine can help regulate the sleep-wake cycle in people with schizophrenia. But if you’re taking Clozapine, a medication commonly used in treatment, it may interact with glycine. So, talk to your doctor about the use of glycine supplements if you’re on any medication.

What Other Supplements Improve Sleep?

Glycine is undoubtedly one of the most effective natural sleep aids, but it’s not the only one.

Other supplements that improve sleep quality are tart cherry extract, magnesium, and L-tryptophan. If you’re looking for an all-in-one formula that contains these ingredients, we reviewed Performance Lab Sleep, one of the best supplements on the market for promoting sleep. 

While glycine works well alone, it also works synergistically with other natural sleep aids. So, you can decide whether to take it alone or add it to your stack.

Other Tips for Improving Sleep

I know this might sound strange after I talked up the benefits of using glycine for sleep, but supplements should be a last resort to improve your sleep.

Here are a few tips for getting better sleep, which, combined with glycine treatment, helped me transform from a night owl into an early bird.

Implement Sleep Hygiene: Sleep hygiene is a collection of habits that stimulate melatonin production and help you unwind at night. This includes avoiding screens and other blue light-emitting devices before bed, making your bedroom cool, dark, and quiet, and investing in comfortable bedding.

Stick to a Strict Sleep Schedule: Going to bed and waking up at a set time trains your body’s internal clock. The more consistent you are, the more regulated your circadian rhythms will become, making it easier to fall asleep at night. Additionally, avoid napping during the day for healthy sleep at night.

Exercise Regularly: Light to moderate exercise 4-5 times a week can dramatically improve sleep efficiency and duration (4). However, try to exercise in the morning because exercising later in the day may disrupt your sleep.

Get Natural Light Exposure: I hate to sound like the Liver King, but exposure to natural light through the eyes and skin is essential for balancing your body clock. A more reliable source, Dr. Andrew Huberman, discusses this on his podcast, which I highly recommend checking out. Just 15 minutes of natural light exposure first thing in the morning can transform your sleep quality at night.

Support Gut Health: There’s an interesting connection between gut health and sleep. Trillions of bacteria in your gut microbiome produce neurotransmitters and hormones involved in sleep, like dopamine, serotonin, melatonin, and GABA. So, researchers believe supporting your gut health may go a long way to improving your overall sleep quality.

Final Thoughts on Glycine for Sleep

In conclusion, glycine is a safe dietary supplement that may support sleep quality by calming your brain, regulating your body temperature before bed, and balancing your sleep-wake cycle.

At the end of the day, improving your sleep takes a multifaceted approach (see what I did there *teehee*). When combined with sleep hygiene and other lifestyle changes, glycine supplements can take your sleep to the next level.

If you’re considering exploring the effects of glycine for a good night’s sleep, check out our recommendations for The Best Glycine Supplements.