L-Theanine And Glycine For Sleep – Can They Help You Sleep Better?

When it comes to L-Theanine & glycine, this combination can have a positive impact on your sleep cycle. This powerful duo is sure to give you a quick, comfy and deep sleep all night long. Wondering how exactly? Read on!

We all lie on our beds listlessly, twisting and turning, trying to juggle with our minds on matters unknown. At such times all we desire is just a good night’s sleep. But not all of us get that right? Sometimes, after a whole impending night’s sleep, staying awake the next day takes a huge toll on your work as well as your mind.

There might be instances wherein you’d feel either excessively sleepy or intensively exhausted. This might be due to insufficient sleep. We understand how important it is to have that good night’s sleep. L-theanine and glycine can help calm you down and put you to a comfortable sleep. Glycine will help you start your morning in a fresh and happy mood.

Why Use L-Theanine & Glycine For Sleep?

In today’s time, Insomnia could be triggered by various factors like environmental factors, physiological factors, or even psychological factors. Also, some underlying conditions include sleep apnea, restless leg syndrome (RLS), and narcolepsy. In a study conducted, it was observed that many students suffer from a suboptimal level of their overall sleep quality [1]. A number of people have found 7 essential oils to be helpful for sleep apnea. Although, the association between many sleep-related factors and sleep behaviors is still unclear and in the field of discovery [2]. 

Although certain unidentified factors might affect your sleep. If you tend to experience sleeplessness or symptoms of insomnia over a long time, it might be a sign of upcoming psychological disorders similar to anxiety and depression. To deal with such symptoms of mood disorders and psychological disruptions certain amino acids can help. L-Theanine and Glycine can help aid such sleep problems and help with better cognitive functioning [3].

Benefits Of L-theanine and Glycine for Sleep And When To Take?

When consumed together, L-theanine and glycine can have immense positive effects on your mind and body. It helps calm anxiety, depression as well as insomnia. L-theanine and glycine for sleep are the best supplements that one could easily find in the market. L-theanine and glycine work on the neurotransmitters in your brain and help break out stressful thoughts. These chemical reactions are healthy and completely natural. 

This combination assures you a deep and comfortable sleep for the night. 

Supplements like L-theanine and glycine when taken together provide you with benefits, like: 

  • Improves your sleep quality for the night 
  • Increases your energy levels for the next upcoming day
  • Helps you fall asleep quickly 
  • Keeps you in a good mood 
  • Has a calming effect on your brain
  • Keeps your body in a restful state
  • Lowers your core body temperature [4] 
  • Keeps you alert 
  • Ensures mindfulness
  • Regulates your sleep cycle
  • Assures you an enhanced quality of sleep [5]

This combination is the most helpful for those who feel like they cannot get deep sleep or a good quality sleep over the night. You should consume these at least 30 minutes before you plan to sleep. When you do this, your mind gets the time to relax and ease out before you shut your eyes for the night. Also, so that you have time to get all comfortable for your long night’s sleep.  

Glycine takes approximately 15-20 minutes to work on your body. L-Theanine has to be consumed between half an hour and one hour before your bedtime. These supplements take time to absorb into your body. Their effects might wear off when you wake up in the morning. If certain effects do tend to last, it may gradually go away by afternoon. 

What Is L-theanine?

L-theanine is a great supplement for getting a good sleep at night. L-theanine helps you relax your body, calm your mind, and puts you in deeper & longer sleep. It has been observed, L-theanine puts people at ease before bedtime and can help you get a deep sleep over the night. The reason why L-theanine is considered to be a great supplement for sleep is that it has a significant influence on the cells of your brain. Being an amino acid, it has certain specific effects on brain chemicals that influence your sleep. 

What Are The Benefits Of L-theanine?

L-theanine as a supplement is considered to be one of the best as it has very minimal side effects. L-theanine provides you with many benefits like:

  • Better mental focus – L-Theanine helps increase cognitive performance, thereby boosting your overall cognitive functioning [6].
  • Improved sleep – L-Theanine boosts the levels of GABA (Gamma-amino Butyric Acid). This in turn lowers the levels of excitatory brain chemicals and enhances the Alpha brain waves which makes your mind calm [7].
  • Relaxation – L-theanine promotes relaxation by reducing the resting heart rate [8].
  • Increased cognitive performance – L-theanine combined with caffeine can help increase focus and alertness. These ingredients naturally occur in stimulating drinks like tea [9]
  • Weight loss – The Umami flavors present in L-Theanine help reduce appetite, lowering your chances of gaining weight [10]. Some other ways to reduce weight efficiently include consuming peptides for weight loss or 5 Thermic foods that could increase your metabolism and help with weight loss. You must avoid certain foods while you are on Saxenda. Alpha Lipoic Acid can help with weight loss too. 
  • Boosting the immune system – L-Theanine enhances your innate immune function by helping with the regular secretion of the immune cytokines in your body. This induces immunologic memory and aids immune response as well [11]. We hope you are boosting your immunity with Vitamin C-rich foods like oranges, etc.
  • Reducing blood pressure – L-Theanine can help people with increased blood pressure levels as it influences your autonomic nervous systems with its anti-stress effects [12]
  • Supporting certain cancer drugs – Since it reduces the intense reactions of doxorubicin L-Theanine can help cancer patients do away with side effects as well [13].

L-theanine Sleep Dosage:

L-theanine helps sleep better and for a longer time. It helps relax your mind, calm your nerves and ease tensed cells in your body, putting you to a cozy sleep. It is always better to consult a medical professional for appropriate dosage before consuming any natural supplements. Moreover, before you prepare to get started on a supplement, be sure to consult your doctor. 

As L-Theanine is not considered to be a medicine, there are no such official guidelines as to how much a person should consume. We recommend you still consult a medical professional before taking these supplements to get a better idea of the dosage required for you. 

What Is Glycine?

Glycine being an amino acid contributes to your body’s cellular growth and health. It is essential for your body’s antioxidant glutathione synthesis. The cells in your body produce glutathione to fight the free radicals. These radicals tend to cause oxidative stress if left unattended. It may also damage your cells, proteins as well as DNA. It was recently observed that when ingested before bedtime, glycine improves your sleep quality, especially for those who experience symptoms of severe insomnia. 

It was seen that in the oral administration of glycine, a major part of the plasma and cerebrospinal fluid was induced with glycine concentrations. This resulted in a significant decrease in the core body temperature, thereby associated with an increase in the cutaneous blood flow of the body. [14]

What Are The Benefits Of Glycine?

Glycine acts as receptor for your body by interpreting and altering your behavior, food intake, sleep, nutrients, etc [15]. Glycine is one of the most beneficial amino acids. It is known to help with the cellular growth of your body [16]. Glycine helps your body in numerous ways, like:

  • Decreases oxidative stress – Glycine decreases the levels of Oxidative stress markers in your liver. The concentration of glutathione (GSH) and y-glutamylcysteine, a significant enzyme for the various functionings of your liver [17]. You could also include antioxidant foods in your diet to reduce oxidative stress. Vitamin E is known to be helpful for some people. 
  • Improves brain and muscle performance – As glycine plays an important role in the synthesis of creatine it also provides you with the energy needed for short bursts of strength and speed. This is one of the major reasons why glycine is preferred by various athletes [18].
  • Aids in Diabetes management and prevention – Glycine supplements encourage insulin response in healthy people. This can help prevent and manage diabetes [19]. Diabetic patients can even opt-in for paneer as it is a great source of nutrition and has no negative effects on immediate consumption. 
  • Decreases risk of heart attack – Since there is a strong inverse genetic effect of hyper insulin anemia on glycine, we know that it can help lower blood pressure. This in turn could reduce the chances of a heart attack [20].
  • Protects your liver from alcohol damage – Glycine can efficiently help minimize liver injuries that are induced by excessive alcohol intake. It prevents ethanol from reaching the liver by activating the first-pass metabolism in your stomach [21]
  • Improves sleep quality – As glycine elevates the level of serotonin in your body, it results in a reduction of symptoms of problems like insomnia. Glycine enhances your sleep quality and helps you gain a healthy sleep cycle [22].

Dosage Of Glycine For Better Sleep

Glycine is usually considered a safe supplement. Although sometimes, glycine might react negatively with certain medications. Hence, you should always consult a doctor before actively adding any supplements to your diet. The typical dosage for an average adult is approximately 2-5 grams. It is recommended to consume no more than 3 grams daily. 

Read here a detailed comparison between Saxenda and Wegovy.


How much Glycine should I take for sleep?

For a good night’s sleep, you could consume a dosage of approximately 3 g and not more. Although this might not make you fall asleep as quickly as other supplements do, they surely do not make you feel any kind of grogginess the next day!

Which Amino Acid is best for sleep?

Although it is known that an eight-hour sleep is a requirement for a healthy adult, the quality of your sleep too matters. Many studies show that amino acid glycine is the best when it comes to sleep [23]

Is Glycine a sedative?

Glycine is not exactly considered as a sedative. But it might help you fall asleep by promoting and enhancing the quality of your sleep. Glycine tends to add calming effects over your body and brain by its ability to lower your core body temperature. Although it may not make you fall asleep quickly, it surely gets you into an energetic mood when you wake up. 

Who should not take Glycine?

Research recommends pregnant women or breastfeeding mothers not take any glycine supplements. It is also recommended that you should not consume any single amino acid for long periods. [24]

When should I take Glycine for sleep?

Based on observations made by various researchers, you can consume glycine and L-Theanine at least 15-20 mins before bedtime. It was observed that it helps you fall asleep quickly and improves sleep quality.

Wrapping Up

When it comes to supplements for sleep, L-theanine and glycine provide your body with immense benefits. L-Theanine & Glycine can help

  • relax your nerves
  • keep your mind cool 
  • ease the tense muscles of your body
  • avoid symptoms of psychological disorders like anxiety & depression. 

You could also try L-Theanine & Magnesium for sleep to help you sleep longer and have a good mood throughout the day. 


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