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!
- 1 Weekly newsletter with the best personal finance tips
- 2 Key Facts
- 3 The best Glycine: Our Picks
- 4 Shopping Guide: Everything You Need to Know About Glycine Supplements
- 4.1 What is glycine and what is its function?
- 4.2 What are the consequences of glycine deficiency?
- 4.3 What foods contain glycine?
- 4.4 What benefits does a glycine supplement have?
- 4.5 Can I treat osteoarthritis with a glycine supplement?
- 4.6 How do you take glycine supplements?
- 4.7 Are glycine supplements safe?
- 5 Buyer's Guide
- 6 Summary
- 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.
The best Glycine: Our Picks
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!
Shopping Guide: Everything You Need to Know About Glycine Supplements
What is glycine and what is its function?
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
|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?
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.
What foods contain glycine?
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|
|Soy protein powder||3|
|Crustaceans (crabs and lobsters)||1,1|
|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?
- 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?
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.
How do you take glycine supplements?
- 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?
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).
(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.
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.
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.
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.
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.
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).
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?
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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.
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