Last updated: September 6, 2020

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Do you feel tired all the time and have trouble falling asleep? Have you started to feel joint pain? You may need a change of habits. Sedentary life and stress can cause all kinds of very unpleasant symptoms. Also, many people underestimate the importance of balanced nutrition.

Glycine is a necessary amino acid for hundreds of bodily processes, such as the regeneration of cartilage or the facilitation of sleep. Some nutrition experts believe that our daily consumption of glycine is much lower than recommended. Could this be causing you fatigue? Keep reading to find out more!

Key Facts

  • Glycine is an essential amino acid. The body can manufacture it in small quantities, but a balanced diet should also provide glycine to avoid nutritional deficiencies.
  • Glycine deficiency has been linked to the onset of obesity, diabetes, and osteoarthritis.
  • Before choosing a glycine supplement, you must consider food allergies and the value for money of the specific product. Capsules and wisteria powder will generally be suitable for vegans and vegetarians.

Our Selection: The Best Glycine Supplements on the U.S. Market

Glycine is a less popular supplement compared to other products like creatine or protein hydrolysate. However, this nutrient has very interesting properties, especially for those who want to enjoy restful sleep, which is everyone. Take a look at our recommendations to find the supplement that best suits you!

Best Glycine Supplement Powder

If you prefer taking your supplements in a powder form, then this product from BulkSupplements will be a great option for you. Previous customers have said that this product helped them to get a better night’s sleep, and lessen aches and pains.

This is a great option if you are looking for something that helps with promoting healthy sleep and contributing to a healthy mood and an overall sense of well-being. Glycine also has a somewhat sweet flavor, so it’s great for adding to smoothies or tea!

Best Vegan Glycine Supplement

These supplements by NOW Supplements are great for those who are looking for vegan capsules. They are corn free, dairy free, egg free, made without gluten, non-GMO, nut Free, and soy free. They also have a NPA A-rated GMP certification which means that every aspect of the NOW manufacturing process has been examined, including their laboratory/testing methods (for stability, potency, and product formulation).

Many past customers praised this product for being a great sleep aid. So if you are looking to take your glycine in a vegan capsule form, this is a great product for you.

Best Natural Glycine Supplement

This glycine supplement by Best Naturals contains no artificial color, flavor or sweetener, no preservatives, and no sugar. All Best Naturals products are manufactured in accordance with Good Manufacturing Practices (GMP), among the highest standards in the world.

Past customers have praised this product for its effectiveness as a sleep aid and joint pain reliever. This is a great option for those looking for natural, preservative-free capsules!

Shopping Guide: Everything You Need to Know About Glycine Supplements

Glycine is an amino acid that is part of collagen, an essential structural protein. This nutrient also normalizes brain function and promotes a good night’s sleep. The human body can manufacture a small amount of glycine, but it also needs constant dietary intake so as not to suffer from a nutritional deficit.

man wakes up

Glycine supplements may improve sleep.
(Source: Guzhva: 62459443/ 123rf.com)

What is glycine and what is its function?

Glycine is an amino acid, that is, one of the “building blocks” that allows the growth and maintenance of body structures. The combination of several amino acids gives way to proteins, molecules that are invaluable in keeping our body in top condition (1).

Although our body can manufacture glycine from other compounds, the amount cannot completely satisfy our needs.

This makes it necessary to get this amino acid from food, even more so when under stress. Consequently, glycine is considered a conditionally essential amino acid (2).

This nutrient forms a third of the body’s collagen, providing resistance to the bones, tendons and body cartilage. Glycine also has a regulatory role in the nervous system, helping to normalize neuronal function. You can find more information about the functions of this molecule in the following table (3):

System, Apparatus or tissue Function of glycine
Connecting (bones, cartilage, blood and others) Collagen synthesis

Formation of other proteins

Hemoglobin creation

Muscular Creatine Synthesis
Metabolic Energy Production
Nervous Signal Transmission (Neurotransmitter)
Immune Control of inflammation

Regulation of white blood cell activity

Digestive Bile acid synthesis

In short, glycine is a very valuable amino acid for our body, acting as a necessary collaborator for the synthesis of different molecules. As a neurotransmitter, it has a regulatory function, sending activation or inhibition signals to your entire body. A deficit of this substance can affect your well-being.

What are the consequences of glycine deficiency?

According to the most recent studies, glycine deficiency could have negative short and long-term health consequences. The lack of this amino acid has been related to diabetes, osteoarthritis and problems to synthesize the bile acids necessary for digestion (4.5).

A diet low in glycine can lead to a lack of this amino acid. In addition, people suffering from obesity, type 2 diabetes or liver problems will have an above-average risk of suffering from this deficit. If the endogenous (body-specific) metabolism of glycine is altered, a congenital disease known as osteogenesis imperfecta (6) will appear.

gelo

Being a component of gelatin, desserts and dishes that contain hydrolyzed collagen will also provide large amounts of this nutrient.
(Source: Hofacker: 33143303/ 123rf.com)

What foods contain glycine?

A balanced diet provides about three grams of glycine a day. However, some experts have doubts about the true nutritional requirements of this amino acid. Some scientists claim that an ideal diet should provide a much higher amount of glycine (10-12 g / day) to achieve optimal protein synthesis (2).

This amino acid is found in high amounts in meat, fish, dairy, and eggs. Being a component of gelatin, desserts and dishes that contain hydrolyzed collagen will also contain large amounts of this nutrient.The following table shows more information about the glycine content of certain foods (7):

Food Glycine content per 100 grams
Gelatin powder 19
Soy protein powder 3
Luncheon meat 1.8
Salmon 1.5
Chicken breast 1,2
Crustaceans (crabs and lobsters) 1,1
Spirulina 0.3
Egg 0.4
Milk (1 glass) 0.1

Most foods rich in glycine have animal origin. For this reason, vegans and vegetarians are estimated to have reduced levels of this nutrient compared to omnivores. Fortunately, there are sources of this amino acid suitable for cruelty-free diets, such as spirulina and soy vegetable protein supplements.

It is very difficult to achieve an intake of 10 grams of glycine a day only through food. After all, meat and seafood are expensive foods. Other sources of glycine, such as animal products, can be unpleasant for some people. A glycine supplement, however, can help you meet this goal.

What benefits does a glycine supplement have?

Glycine supplements are used in the field of sports nutrition and in the field of medicine to try to improve the well-being of consumers and patients. If you focus on analyzing human clinical trials, you can see that glycine supplementation has three potential benefits:

  • Improved rest: The consumption of glycine supplements could promote sleep and improve sleep (8).
  • Fatigue relief: Glycine supplements have been shown to reduce the feeling of fatigue in the subjects studied. This effect could be due, simply, to the improvement in the quality of sleep that is associated with the consumption of glycine (9).
  • Neural Protection: In medicine, glycine supplements have been used to treat mental conditions like schizophrenia. Experts believe that this amino acid could consequently stabilize neuronal function and improve intellectual performance in some people (10).

The consumption of glycine supplements will help to complete the recommended daily amount (CDR) of this nutrient. Remember that this amino acid is essential for the synthesis of collagen, a protein that gives bones resistance and skin elasticity, among other benefits.

Can I treat osteoarthritis with a glycine supplement?

Many people are interested in glycine supplements as a treatment for osteoarthritis, a degenerative process that reduces the integrity of tissues. This disease especially affects older people, causing joint pain, reducing their mobility and worsening their quality of life (11).

Destruction of collagen-rich articular cartilage is considered a possible cause of osteoarthritis.

It is therefore not surprising that many people are inclined to try glycine, a component essentially made of collagen, to remedy this condition. But, is this supplement your best asset to deal with joint degeneration?

The truth is that a glycine deficit has been identified to negatively affect the structure of joint collagen. However, more studies are needed before it can be stated that glycine benefits the joints. In in vitro studies, glycine has been shown to be able to stimulate cartilage synthesis (2.5).

However, remember that the results of animal or cell tests do not always translate into real benefit in humans. If you want to use a glycine supplement for osteoarthritis, consume it to prevent a deficiency. Otherwise, we recommend that you opt for other supplements, such as glucosamine.

food with glycine

Eggs, milk, meat, and seafood are natural sources of glycine.
(Source: Dolgachov: 53927722/ 123rf.com)

How do you take glycine supplements?

Glycine supplements are sold in different formats. In the “Buyer’s Guide” section we will discuss in more detail the types of glycine supplements available. Fortunately, there are a number of general guidelines that you can follow to get the most out of your glycine supplement regardless of its format (12):

  • Daily dose: The best clinical results have been described with doses ranging from 3-5 grams of glycine per day. However, you will find that most supplement manufacturers use more modest doses (0.5 – 1 g) to meet the classical CDR of 3 grams of glycine per day.
  • Time of day: If this supplement is used to improve the quality of sleep, it is advisable to take it a few minutes before bed.
  • Accompanied by food: It has been studied that accompanying main meals with a glycine supplement could prevent unwanted increases in blood sugar levels.

Most supplements need to be used for a minimum of 30 days before showing any effect. Surprisingly, the benefits of glycine on the quality of sleep are manifested more quickly. A 2012 Japanese study described satisfactory results with this supplement after just three days of supplementation (13).

Are glycine supplements safe?

In general, glycine is a safe supplement. Doses of up to 60 grams a day of this amino acid have been used without adverse effects. For this reason, it is considered very difficult to overdose with the consumption of glycine supplements. The most common side effects are gastrointestinal complaints (abdominal heaviness and flatulence) (14).

This product should not be used without medical supervision by people who follow a treatment for serious psychiatric pathologies, such as schizophrenia. In these cases, glycine supplementation could alter the function of clozapine-type antipsychotic drugs, worsening the disease state (14).

Glycine could have antiplatelet actions, preventing the binding of platelets.

(blood cells in charge of controlling and limiting bleeding). People taking anticoagulant or antiplatelet medication should consult their doctor before taking glycine, as should individuals with congenital platelet abnormalities (15).

Finally, keep in mind that these nutritional supplements have not been shown to be safe during pregnancy or lactation. For this reason, it is preferred that pregnant or breastfeeding women avoid consuming glycine supplements. Children under the age of eighteen should also not take this supplement without prior medical authorization.

soy peas

Soy protein is one of the few plant sources of glycine.
(Source: Yindeesuk: 61660391/ 123rf.com)

Buyer’s Guide

If you want to introduce a new glycine supplement into your diet plan, we recommend that you carefully read this section first. Our purchasing criteria will focus on breaking down the less conspicuous (but equally important) aspects of glycine supplements. This way, you can choose a product that suits your lifestyle.

Vegan Diet

If you are vegan or vegetarian, breathe easy. Although animal products are the richest in glycine, in the world of supplementation this amino acid is usually obtained from plant sources. Most of the glycine nutritional supplements will be vegan friendly. Choose cellulose-coated (vegetable) capsules and avoid gelatin covers.

food with glycine

Glycine, proline, and lysine are three amino acids present in gelatin.
(Source: Naumenko: 54514888/ 123rf.com)

Allergies and Intolerances

Allergies to glycine, an amino acid that is an essential part of the body’s tissues, are incredibly rare. However, intolerance reactions to additional components of the supplement (additives and capsules) may occur. If you are allergic to soy, gluten or nuts, be sure to read the list of ingredients before buying.

Format

You will find that glycine supplements are sold in different formats. The most popular are mixing powder (which allows you to choose a more personalized dose) and capsules (which simplify supplementation).

There are also newer formats, which combine liquid and solid forms and that add other nutrients (such as vitamins and minerals).

Another less well-known way to use glycine is through creams or gels. This form is used to accelerate wound healing or to improve the appearance of ulcerative lesions. Unfortunately, finding these can be difficult in today’s market.

Michael J. Breus, Ph.D.Clinical Psycologist

“As a neurotransmitter, glycine both stimulates and inhibits cells in the brain and central nervous system, affecting cognition, mood, appetite and digestion, immune function, pain perception, and sleep. “.

Conservation and Expiration

After the expiration date of a glycine supplement has passed, the amino acid will gradually lose its effectiveness. Manufacturers generally advise getting rid of expired glycine supplements. However, if the quality of the supplement is good, it could be used for a few more months without giving up its effects.

Keep your glycine supplement in a dry place, protected from extreme temperatures, sunlight and aggressive odors. After use, check that the bottle or container of the supplement has been tightly closed. Avoid this supplement coming into contact with water (this is especially important in the case of powder).

Price-Performance Ratio

Glycine supplements are quite affordable, ranging from $10-20 per container (90 capsules or 500 grams of powder). The newer formats will be priced higher, as will combinations of glycine and other ingredients (such as silicon or creatine).

Summary

Glycine is an important compound for our bodies. However they cannot manufacture a sufficient amount of this amino acid alone, so we are forced to obtain it through diet. Surprisingly, some experts believe that food does not offer us all the glycine that our body needs to regenerate properly.

An additional contribution of glycine in the form of a nutritional supplement could normalize tissue regeneration and prevent premature aging. Its beneficial effects on relaxation will help you achieve a restful sleep that keeps fatigue at bay. If you want to feel young, healthy and energetic, why not try glycine?

If you liked our guide on glycine supplements, please leave a comment and share this article!

(Source of featured image: Dzyuba: 61699441/ 123rf.com) 

References (15)

1. Schemmer P, Zhong Z, Galli U, Wheeler MD, Xiangli L, Bradford BU, et al. Glycine reduces platelet aggregation. Amino Acids [Internet]. 2013 Mar 8 [cited 2019 Dec 18];44(3):925–31.
Source

2. Glycine: Uses, Side Effects, Interactions, Dosage, and Warning [Internet]. [cited 2019 Dec 18].
Source

3. Bannai M, Kawai N, Ono K, Nakahara K, Murakami N. The Effects of Glycine on Subjective Daytime Performance in Partially Sleep-Restricted Healthy Volunteers. Front Neurol [Internet]. 2012 [cited 2019 Dec 18];3.
Source

4. Glycine | Winchester Hospital [Internet]. [cited 2019 Dec 18].
Source

5. Sen R, Hurley JA. Osteoarthritis [Internet]. StatPearls. 2019 [cited 2019 Dec 18].
Source

6. Heresco-Levy U, Ermilov M, Lichtenberg P, Bar G, Javitt DC. High-dose glycine added to olanzapine and risperidone for the treatment of schizophrenia. Biol Psychiatry [Internet]. 2004 Jan 15 [cited 2019 Dec 18];55(2):165–71.
Source

7. Inagawa K, Hiraoka T, Kohda T, Yamadera W, Takahashi M. Subjective effects of glycine ingestion before bedtime on sleep quality. Sleep Biol Rhythms [Internet]. 2006 Feb [cited 2019 Dec 18];4(1):75–7.
Source

8. Yamadera W, Inagawa K, Chiba S, Bannai M, Takahashi M, Nakayama K. Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep Biol Rhythms [Internet]. 2007 Apr [cited 2019 Dec 18];5(2):126–31.
Source

9. Foods highest in Glycine [Internet]. [cited 2019 Dec 18].
Source

10. Yang W, Battineni ML, Brodsky B. Amino Acid Sequence Environment Modulates the Disruption by Osteogenesis Imperfecta Glycine Substitutions in Collagen-like Peptides †. Biochemistry [Internet]. 1997 Jun 10 [cited 2019 Dec 18];36(23):6930–5.
Source

11. de Paz-Lugo P, Lupiáñez JA, Meléndez-Hevia E. High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: acute glycine deficiency could be an important cause of osteoarthritis. Amino Acids [Internet]. 2018 Oct 13 [cited 2019 Dec 18];50(10):1357–65.
Source

12. Alves A, Bassot A, Bulteau A-L, Pirola L, Morio B. Glycine Metabolism and Its Alterations in Obesity and Metabolic Diseases. Nutrients [Internet]. 2019 Jun 16 [cited 2019 Dec 18];11(6):1356.
Source

13. Razak MA, Begum PS, Viswanath B, Rajagopal S. Multifarious Beneficial Effect of Nonessential Amino Acid, Glycine: A Review. Oxid Med Cell Longev [Internet]. 2017 [cited 2019 Dec 18];2017:1–8.
Source

14. Meléndez-Hevia E, de Paz-Lugo P, Cornish-Bowden A, Cárdenas ML. A weak link in metabolism: the metabolic capacity for glycine biosynthesis does not satisfy the need for collagen synthesis. J Biosci [Internet]. 2009 Dec 3 [cited 2019 Dec 18];34(6):853–72.
Source

15. H. Stipanuk M, A. Caudill M. Biochemical, physiological, and molecular aspects of human nutrition. 3rd edition. Elsevier; 2013. 948 p.
Source

Why you can trust me?

Schemmer P, Zhong Z, Galli U, Wheeler MD, Xiangli L, Bradford BU, et al. Glycine reduces platelet aggregation. Amino Acids [Internet]. 2013 Mar 8 [cited 2019 Dec 18];44(3):925–31.
Go to source
Glycine: Uses, Side Effects, Interactions, Dosage, and Warning [Internet]. [cited 2019 Dec 18].
Go to source
Bannai M, Kawai N, Ono K, Nakahara K, Murakami N. The Effects of Glycine on Subjective Daytime Performance in Partially Sleep-Restricted Healthy Volunteers. Front Neurol [Internet]. 2012 [cited 2019 Dec 18];3.
Go to source
Glycine | Winchester Hospital [Internet]. [cited 2019 Dec 18].
Go to source
Sen R, Hurley JA. Osteoarthritis [Internet]. StatPearls. 2019 [cited 2019 Dec 18].
Go to source
Heresco-Levy U, Ermilov M, Lichtenberg P, Bar G, Javitt DC. High-dose glycine added to olanzapine and risperidone for the treatment of schizophrenia. Biol Psychiatry [Internet]. 2004 Jan 15 [cited 2019 Dec 18];55(2):165–71.
Go to source
Inagawa K, Hiraoka T, Kohda T, Yamadera W, Takahashi M. Subjective effects of glycine ingestion before bedtime on sleep quality. Sleep Biol Rhythms [Internet]. 2006 Feb [cited 2019 Dec 18];4(1):75–7.
Go to source
Yamadera W, Inagawa K, Chiba S, Bannai M, Takahashi M, Nakayama K. Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep Biol Rhythms [Internet]. 2007 Apr [cited 2019 Dec 18];5(2):126–31.
Go to source
Foods highest in Glycine [Internet]. [cited 2019 Dec 18].
Go to source
Yang W, Battineni ML, Brodsky B. Amino Acid Sequence Environment Modulates the Disruption by Osteogenesis Imperfecta Glycine Substitutions in Collagen-like Peptides †. Biochemistry [Internet]. 1997 Jun 10 [cited 2019 Dec 18];36(23):6930–5.
Go to source
de Paz-Lugo P, Lupiáñez JA, Meléndez-Hevia E. High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: acute glycine deficiency could be an important cause of osteoarthritis. Amino Acids [Internet]. 2018 Oct 13 [cited 2019 Dec 18];50(10):1357–65.
Go to source
Alves A, Bassot A, Bulteau A-L, Pirola L, Morio B. Glycine Metabolism and Its Alterations in Obesity and Metabolic Diseases. Nutrients [Internet]. 2019 Jun 16 [cited 2019 Dec 18];11(6):1356.
Go to source
Razak MA, Begum PS, Viswanath B, Rajagopal S. Multifarious Beneficial Effect of Nonessential Amino Acid, Glycine: A Review. Oxid Med Cell Longev [Internet]. 2017 [cited 2019 Dec 18];2017:1–8.
Go to source
Meléndez-Hevia E, de Paz-Lugo P, Cornish-Bowden A, Cárdenas ML. A weak link in metabolism: the metabolic capacity for glycine biosynthesis does not satisfy the need for collagen synthesis. J Biosci [Internet]. 2009 Dec 3 [cited 2019 Dec 18];34(6):853–72.
Go to source
H. Stipanuk M, A. Caudill M. Biochemical, physiological, and molecular aspects of human nutrition. 3rd edition. Elsevier; 2013. 948 p.
Go to source