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Glycine is a great supplement to reduce inflammation, build muscle and joint tissue, reduce wrinkles, improve your sleep, and heal your liver all in a breakfast shake.


Glycine is one of many amino acids that commonly comprise protein. It is the smallest of all amino acids and is incredibly important for the synthesis of other amino acids, glutathione, creatine, heme, RNA/DNA, and it can also help with the absorption of calcium in the body (R, R2).

The Glycine That I Take

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  • Longevity8/10
  • Inflammation9/10
  • Mood9/10
  • Cognition8.5/10
  • Energy8/10


  • Great for reducing all kinds of inflammation, especially those with an overactive immune system.
  • Great for cancer.
  • Good for detoxing (heavy metals).


  • Has anti-fertility effects.
  • Doesn’t absorb through the gut or brain barrier well (if it’s not this brand).
  • Doesn’t taste good, but this brand has no taste.
  • Don’t take if you are suffering from loose stools.
  • May cause drowsiness.

1) Glycine is an Anti-inflammatory

Glycine acts directly on inflammatory cells to suppress the activation of transcription factors, the formation of free radicals, and inflammatory cytokines (R).

Glycine reduces TNF-alpha and increases interleukin-10 (R).

Glycine can reduce TNF-receptor I levels, and raise interferon (IFN)-gamma levels in diabetic patients (R).

Glycine significantly inhibits NF-κB activation and IL-6 production in heart artery cells (R).

Glycine increases the anti-inflammatory IL-10 production in toxin-induced liver injury, increasing rat survival rates (R).

Glycine significantly improves toxin-exposed mice survival rates by lowering TLR4 and TNF-alpha and inhibiting Nf-kB (R).

Feeding rats diets high in glycine (5%) totally prevented death after exposure to an injection of a toxin (E Coli) by blunting TNF-alpha. Whereas 50% of the control group died within 24hrs (R).

In this same study, glycine fed rats who had liver damage and also injected with a toxin had an 83% survival rate, whereas the non-glycine control group had 0% rate of survival (R).

Glycine plays an important role in reducing oxidative stress in the body (R).

As a precursor to glutathione, glycine can restore previously lowered levels of glutathione (R, R2).

Glycine is recommended to the elderly because glutathione levels naturally fall with age (R).

2) Glycine Helps You Sleep and Function Better on Less Sleep

Taking glycine before sleep improves sleep quality and sleep efficacy by increasing the time to fall asleep, and slow wave deep sleep (R).

After taking glycine for sleep, the following day subjects had lessened daytime sleepiness and improved performance of memory recognition tasks (R).

Glycine helps improve REM sleep and decrease non-REM sleep (R).

3g Glycine given to volunteers before sleeping resulted in improvements in fatigue, ‘liveliness and peppiness’, ‘clear-headedness’ (R).

Glycine appears to improve daytime sleepiness and fatigue induced by sleep deprivation (R).

Glycine affects certain neuropeptides in the SCN (suprachiasmatic nucleus) in the region in the hippocampus which regulate the circadian rhythm (R).

Specifically, glycine increases VIP, which is critical to the circadian rhythm.

This effect on the SCN indirectly contributes to reducing sleepiness and fatigue induced by sleep restriction (R).

3) Glycine Improves the Skin

Glycine (through the consumption of collagen) significantly improves skin elasticity in elderly women and improved skin moisture and water loss (R, R2)

Collagen peptide is beneficial in suppressing UV-B induced skin damage and photoaging (R).

Women taking 2.5g of collagen peptide for 4 weeks significantly reduced eye wrinkles by 20%, with positive effects lasting after the study ended (R).

At 8 weeks, collagen significantly improved skin content of procollagen type I by 65%, and elastin by 18% (R).

Glycine increases the speed by nearly double of which skin ulcers heal (R).

Glycine enhances wound healing in diabetic animal models (R).

Glycine in combination with l-cysteine and dl-threonine topically applied to leg ulcerations significantly improved the degree of wound healing and decreased pain (R).

4) Glycine Helps the Gut

Glycine inhibits stomach acid secretion and protects against chemical and stress-induced ulcers (R).

Glycine possesses significant anti-ulcer activity (R).

Glycine prevents chemically induced colitis in animal models (R).

Glycine prevents alcohol-induced stomach lesions (ex. ulcers) when used as a pretreatment in animal models (R) .

Glycine can dramatically help increase the tolerability of Aspirin in the upper GI tract(R).

In small intestine grafts, glycine improves smooth muscle dysfunction after transplantation as well as reduces inflammation (R).

Glycine, but not L-arginine, is able to maintain intestinal wall integrity and mucosa in cancer treatment irradiation in animal models (R).

Glycine has protective effects against oxidative stress in intestinal cells in test tubes(R).

5) Glycine May Help Your Thyroid

Glycine might also increase the conversion of T4 to T3 in the liver. (but this has only been studied in Trout) (R).

6) Glycine Can Help the Brain

Small amounts of glycine have been shown to dilate the microvessels in the brain by up to 250% (R, R2).

In rats with alcohol poisoning, glycine was able to reduce the accumulation of cholesterol, free fatty acids, and triglycerides in blood circulation, liver, and brain.  Ultimately, this decreases swelling in the brain (R).

A shortage of glycine in the brain can negatively influence the brain neurochemistry, synthesis of collagen, RNA/DNA, porphyrins, and other important metabolites (R).

7) Glycine Helps Mental Illnesses

Glycine supplementation has been shown in one instance over the course of 5 years to significantly reduce symptoms of OCD and body dysmorphic disorder (R).

Glycine has positive results when used in the treatment of obsessive-compulsive disorder in adults (R).

Glycine supplementation significantly reduced symptoms of schizophrenia (R).

In treatment-resistant schizophrenia glycine improved cognitive and depressive symptoms (dosed at 0.8g/kg).

Interestingly, the group who made the most improvement were also the most deficient in glycine (R).

Glycine helps in chronic schizophrenia by increasing NMDA-receptor-mediated neurotransmission (R).

This effect on NMDA-receptor-mediated neurotransmission allows for glycine to work synergistically with schizophrenia medication (R).

8) Glycine May Help Combat Depression

Depression is associated with lower levels of blood glycine, as well as high levels of taurine (R).

9) Glycine May Reduce Obesity

Glycine increases adiponectin, which can help with weight loss (R).

10-11) Glycine Helps With Diabetes and Metabolic Disorders

Glycine helps with diabetes and metabolic disorders (R).

Glycine intake decreases free fatty acids in blood, fat tissue cell size, and blood pressure in sucrose-fed rats (R).

Glycine reduces glycated hemoglobin (A1C), a risk factor associated with poor blood glucose management in patients with type 2 diabetes. The dose was 5g/d (R).

5g Glycine taken in the morning increased total insulin response in healthy first-degree relatives of Type 2 diabetes patients (R).

Glycine stimulates the secretion of a gut hormone (glucagon) that helps insulin remove glucose from circulation (R).

Diabetic patients have 26% lower blood glycine levels than “normal” population (R).

Glutathione synthesis is restored in patients with uncontrolled diabetes and hyperglycemia with glycine (+cysteine) added to their diet (R).

Glycine helps patients with oxidative stress in the development of metabolic syndrome (R).

12) Glycine May Help Glucose Balance

Glycine helps with lipid profiles in insulin-resistant patients (but not insulin resistance) (R).

Glycine can help with positive glucose management by stimulating the production of Glucagon, a hormone which helps potentiate the action of insulin (R).

Glycine helps HIV patients restore insulin sensitivity (R).

13) Glycine Helps Reduce Inflammation From High Fructose

In mice fed with various types of sugar, TNF-alpha is significantly higher in mice fed fructose (R).

Glycine has protective properties against the harms of Fructose by its ability to prevent the release of the inflammatory cytokines (TNF-α, IL-6) release with fructose exposure (R).

14-15) Glycine Helps Your Heart and Lowers Blood Pressure

In heart attack conditions (Post-ischaemic reperfusion) glycine can prevent the death of heart muscle cells by inhibiting mitochondrial permeability (R).

Glycine depletion within cells during a heart attack (hypoxia/re-oxygenation) makes the heart cells more vulnerable to cell death (R).

Glycine can lower systolic blood pressure in patients with metabolic syndrome(R, R2).

16-18) Glycine Helps with Joints, Bones, and Muscle

Glycine can help body composition and muscle strength in people with HIV (R).

Glycine protects against (peptidoglycan polysaccharide -induced) arthritis (R).

Glycine combined with green tea benefits tendon recovery processes after tendinitis by better collagen bundling organization (R).

Glycine can potentially help in menopause because of its estrogen-like bone protective effects (R).

Glycine plays a large role in maintaining the health of mice suffering from osteoarthritis (R).

19) Glycine Helps the Liver

Glycine prevents lactate dehydrogenase leakage (a cell death indicator) in rat liver cells in test tubes (R).

In rats with alcohol poisoning, feeding glycine reduced accumulation of cholesterol, phospholipids, free fatty acids and triglycerides in blood circulation, liver, and brain, ultimately reversing liver disorder associated with fat accumulation (R).

In rats deficient in choline and methionine, glycine supplementation prevents liver injury (R).

Glycine reduces liver damage and decreases mortality rates in rats suffering from a serious bacterial infection (sepsis) (R).

Glycine was able to maintain Vitamin D blood levels in animals models with induced liver disease (bile duct ligation), and also slow liver damage (R, R2)

Supplementation of glycine for five days in animal models prior to complete or partial liver donation significantly inhibited liver injury and liver-related enzymes (R).

Glycine maintains mitochondrial activity and bile composition in liver injury in animals (R).

20) Glycine Slows Alcohol Absorption

Glycine slows alcohol absorption by reducing the rate at which the stomach absorbs alcohol as well as empties into the intestine (R).

Blood alcohol levels were significantly lower in individuals who had consumed glycine prior to intoxication over controls who had not (R).

21) Glycine Helps the Kidneys

Kidney tubes (proximal tubules) are resistant to oxygen deprivation damage if glycine is present in the test tube (R).

22) Glycine Prevents Cavities

In rat models, supplementation with 4% glycine caused a 65.7% reduction of cavity occurrence (R).

23) Glycine Can Help Stroke Patients

In ischemic stroke patients, taking glycine 1-2g/day normalized autoantibodies, reduced glutamate and aspartate levels, increased GABA concentrations, and reduces lipid peroxidation  (R).

Those who consume regularly low doses of glycine actually reduce damage in future strokes (R).

The glycine treatment at the dose of 1-2g/day was accompanied by a tendency to a decreased risk of dying over 30-days  (R).

500mg/kg glycine combined with 500mg/kg Piracetam improved cognitive impairments and promoted recovery in the prefrontal cortex in animals with a stroke (R).

Note: Some of the scientific sources obtained for this article was found on Vladamir Heiskanen’s blog.

Dietary requirements

Glycine is sometimes called a semi-essential nutrient because it is both made by the body and obtained from food, although the combination of the two is not always enough to supply various tissues, bone, muscle, and skin with what is needed.

The average person usually can make roughly 3g of glycine, and usually consume 1.5 – 3.0 g from food, making their daily intake from roughly 4.5 – 6g (R).

Clinical and nutritional studies over twenty years indicate that the amount of glycine available in humans is not enough to meet metabolic needs and that a dietary supplement is appropriate (see the body of study) (R).

One study suggests that humans may fall significantly short of the amount needed for all metabolic uses – by about 10 g per day for a 70 kg (154 lbs) human (R).

How Much Glycine Do I Take?

I try to get in about 3-5g of extra glycine daily, either from pure Glycine Powder or from 20g of Collagen.

Side Effects of Glycine

Slight sedation is a possible side effect of taking Glycine (R). This is often why it is recommended to take in the evening.

Potential Downsides of Glycine

In a Japanese study of nearly 30,000 patients, the risk of dying after stroke may be increased by meat consumption. The scientists suggest it is the increase in glutamic acid and glycine which cause this correlation (R).

Glycine is not recommended to take while suffering from diarrhea.  It may worsen the condition and lead to poor rehydration (R).

Top Foods with The Highest Glycine Content

You can get a good amount of glycine from glycine, collagen or gelatin.

A list of foods high with glycine:

  • Gelatin
  • Whitefish
  • Soy Protein Isolate
  • Chicken
  • Turkey
  • Pork
  • Beef

Collagen contains 22 -30% glycine. Adding 1-2 tbls. a day to a breakfast smoothie will give you an additional 2.5-3.5g glycine per Tbls.

Buy Glycine

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The information on this website has not been evaluated by the Food & Drug Administration or any other medical body. We do not aim to diagnose, treat, cure or prevent any illness or disease. Information is shared for educational purposes only. You must consult your doctor before acting on any content on this website, especially if you are pregnant, nursing, taking medication, or have a medical condition.


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  • Sally

    I would like to take glycine for all its benefits, but whenever I take it, I am awaken at night with a racing heart. Why is this happening?

  • Amy

    Could Glycine provoke Anxiety attacks? I’ve noticed that whenever I take Glycine, I suffer acute anxiety attacks. I suspect the reason may be for the possible increase in Dopamine, but I could be wrong. What do you think?

  • ted bennet

    I urge you to dive in deep with Dr Ray Peat… The Ray Peat forum and assorted other Ray Peat facebook groups. Peat is a researcher and PhD biologist. This will take some time…but will be well worth it. Many of “our” maladies, dysfunctions, etc come down to straight miss-use of our own biology knowingly or by accident, according to Dr Peat. I’m paraphrasing here. Good Luck.

  • SandraB


    Research the following key words on youtube, it will point you in the right direction:

    Abram Hoffman , Vitamins, Schizophrenia ,Orthomolecuar Medicine
    Julia Ross, Mood Cures, Amino Acids
    John GRay, Autism

    Each Author have published books so head out to your local public library and check them out.

    Good Luck!

  • Doris C. Meshack

    i am trying to find supplements to help my 35 year old son who has schizophrenia (autism). He has been on fluphenazine, risperdone, Benztropine and sertraline. I want to start using vitamins for him.

  • Heather Rae, INHC

    I forgot to mention, we may all be low in glycine due to use of RoundUp/glyphosate in the industrial food system and in our water.
    Stefanie Seneff at MIT is looking at glycine in collagen and glutathione, finding that glyphosate is an analog of glycine.
    Scary stuff, really. (I tested off the charts for glyphosate and organophosphates after working in a commercial nursery for a year)

  • Heather Rae, INHC

    I am taking glycine based on some clues about my own body, rather than guessing at how supplementation works in my unique body and mind.
    After digging into the results of my organic acid test AND after immersing into classes on functional medicine and MethylGenetic Nutrition for several years AND after running my 23andME through an extensive de-coder … AND after compiling all that data into software, I have some information about *me* which is essentially irrelevant to anybody else, albeit interesting (maybe), upon which to do experimentation.
    My husband gets the runs from the amount of glycine that we’ve been taking and, so, he’s cutting it down or out. I barely notice the same dose at all, and am upping it, as well as taking a glutamate scavenger and addressing a glutathione deficiency (and other nutritional and toxin/heavy metal issues with an awareness of my particular genetic variants, a study in its infancy).
    This plan of action is bio-individual, evidenced by my unique data set.
    No doctor could get me here, so I’ve done it myself, a la Joe!

  • John Firth

    Reference links are not working
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    1. Helen
  • Carolyn

    Try taurine with glycine

  • Carlos

    The study you linked says the opposite: “There were no significant changes in the urinary excretion of oxalate, …” and “These results provide no biochemical evidence of an increased risk of renal lithiasis due to glycine irrigation during transurethral operations”. However, if taken as collagen (two of the listed products in the article) that promotes the formation of oxalates, especially if you are deficient in vitamin B6. So for Kath above I suppose the recommendation would be do take Glycine, just not with, or in the form of, Collagen

  • Harold Powell

    I have looked into dmg and glycine concerning diabetes. One aslect is that dmg is changed in most people directly to glycine. Being that beef gelatin is high in glycine and other similar acting amines, to me, since I have had great benefit in using it, I recommend beef gelatin as very economical and inclusive( budget management “

  • Leon

    Hi, Joe, I am relatively new to this site, and I think your work is great! I follow a whole-food plant-based diet (vegan), but I still like your page on it as I think it´s good of you to be sceptic of every diet, including veganism.
    Now, on glycine; I notice you claim it has anti-fertility effects. I can not find any source on this page on this topic. And instead, I actually found three sources on the internet conlucing glycine actually has pro-fertility effects: page 357-363

    I look forward to your response!

  • Kath

    Collagen is high in oxalate which is an issue for me. Do you if there are oxalates in Glycine?

    1. Evguenia Alechine

      Hi Kath, glycine produces oxalate in the body.

  • Justin

    Potassium has consistently tested normal. Does glycine deplete potassium?

  • Crazy Justin

    I suffer from sensitivity to supplements due to poor glycine conjugation. Glycine supplementation worked like magic for a couple weeks then in the ULTIMATE IN CRUELTY, I became intolerant to glycine. It caused low energy, low HR and very sore muscles. Any reasons for this? Could extra methyl folate help? Thanks.

  • Sanderson

    Check your potassium levels that might be the cause of your cramps in your legs

  • Justin

    I’m convinced that poor glycine conjugation is the cause of my sensitivity to supplements. Glycine has been very effective in combating this problem but has also caused sore muscles esp. in the hamstring and calves. The sore muscles are preferable to the sensitivity but I’d like to be free. Any ideas?

  • Antonio Ray

    The glycine needs to be of high quality and pure. I don’t know about this brand getting a better absorption then other brands other than the reason I use the brand in the first place. This is why I use it and might be why the person said that; the reason I use now brand is because most of their products are pharmaceutical grade. Basically meaning the quality is most likely of high-quality and you’re going to get what they say is in it. Other brands , if not stating the process of the product then you’re not really sure about the quality. Unless I really know the brand I always look for pharmaceutical grade products or I don’t buy it. I’m just a slightly above average guy that happens to be a Privet Personal Fitness Trainer; the supplements I put into my body basically helps me with every part of my life thats why I take them individually so I can monitor the input of each one..
    Antonio Ray Denton Tex

  • Elvia Elnora Tucker

    I was told that Glycine would help with my gout flareups. Is this correct?

  • Grace Flower

    Try adjusting the dose. My son 13, was taking 2 grams a day and he couldn’t sleep well for days. He got very manic. He takes 100 mg everyday and he’s great (we use it to improve liver function for a metabolic problem).

  • Joe

    It’s the NAC that causes your drowsiness. But I take glycine at night anyway cuz it helps improve sleep. Try doing that.

  • Sam

    Yeh he did not say what brand. Glycine is an amino acid and if any brand claims 100% pure then I dont see how another brand can claim what they sell is any better if its also 100% pure as it will have the exact same chemical structure. I read a study that showed vitamin C improved absorption by 20% in dogs used in the study. I definitely have improved sleep and skin when I take it so its getting absorbed by me at 3gm when it take it at night (empty stomach)

  • Ron Faltinsky

    I prefer glycine from: Founded in 1909, Ajinomoto, Co., Inc. was one of the first companies in Japan to conduct extensive research on the various properties of amino acids. In the 1950s, this emphasis on amino research culminated in our entry into the pharmaceutical industry. The company’s development of essential amino acids led to the world’s first use of intravenous amino acid therapy in hospitals in 1956. Swanson has a glycine product called AjiPure that is reasonably priced. I would guess NOW glycine comes from China.

  • Mark Patterson

    Correction: This study ( is cited saying that glycine “Glycine helps improve REM sleep and decrease non-REM sleep”. That’s not what the study says. The study says that glycine shortened NREM sleep latency. So you are able to achieve NREM (SWS) more rapidly — which is a good thing.

  • Remy

    How do DMG and glycine compare? Do they have the same effects? Is one better than the other for any specific conditions like diabetes?

  • Mick

    Following recommendation also on this site I started supplementing with glycine. Wow, wow, wow! Three weeks of supplementation and tendons over my let ankle are actually ending to heal. Dose was rather high: around 5 grams a day. Nothing was working before, and I supplemented with just about everything, so I had all the necessary cofactors required to heal, only glycine was missing and it worked just great.

    But there is one terrible downside to it !!!

    I am so sleepy, drowsy and tired that I am unable to function normally. Of course I’m off of it for a week now (tendons still healing) but it’s still like I am two hours awake and then I need two hours of sleep during the day. It’s not a good feeling, like resurrecting a zombie. Green tea, coffeine helps a little but I still get that overwhelming feeling of drowsiness and sooner or later I will have to go to sleep during the day. I also take glutamine and NAC as these are supposed to help to get rid of glycine and during the process one might just get more glutathione, however I don’t feel like these cause any improvement of drowsiness.
    The ideal solution would be to counteract NMDA receptor (or chloride channel – which one it is actually that causes drowsiness?) binding of glycine (or whatever mechanism it uses to makes one drowsy) so that I could continue supplementation and heal some more.

    If anyone has an idea, please share.

    1. Nattha Wannissorn

      Maybe try a food source of it, like gelatin and bone broth? Or just take it before bed and reduce the dose.

  • Shelley

    You said it inhibits stomach acid secretion. Is that good? Don’t many of us need more stomach acid, not less?

  • Tammy Plourde

    Thank you for the great article. Under the heading “The Glycine That I Take” you wrote under “cons” of taking glycine that glycine “doesn’t absorb through the gut or brain barrier well(if it’s not this brand)” Can you please provide a source for that information or relate how you came to that conclusion? I just ordered a large amount of another brand. Hope i’m not wasting my money. Thank you.

  • Sara

    Do you have any information for increasing GAD enzyme (for those of use with GAD variants) too help the body convert glycine to GABA? I am sensitive to free glutamate and glycine is also excitatory for me (and others).

  • Mike

    It raised my blood pressure to an alarming rate . I would think twice about taking glycine until consulting with your doctor .

  • Ted Hu

    Collagen has glutamate and glutamic acid. Neurotoxic for those already with sufficient glutamate, which is most people.

    1. Shelley

      I would love to see a caution added to the article if this is true. I am high in glutamate. What are the most common tests for glutamate levels?

  • altamisal

    You are correct, Harry W. Most people as they get older, need more stomach acid, not less. But I’ve only skimmed the post so far and I don’t see mention of stomach acid…?

  • Arieh Shishirin

    Assuming a high protein diet combined with regular amateur weight lifting (150g for a 70kg male) Whereby protein comes from varied sources (lean meats,dairy,legumes,greens) Should one really bother with adding individual amino acids?

    I see 4 cases:
    1some amino acids for some people should be kept really high in the diet
    2acute fasted fasted megadosing
    3trying to keep a certain ratio of things (something in the diet cancels out glycine benefits for 4those who would otherwise need it)

    the average person might have as low as 40-60g protein in a 2mcal diet, it would be easy to increace his intake of certain aminos by supplementing .

    a person who eats 150g on 2000kcal/day (that would be 30% protein diet, fairly hard to eat that way unless you aim for it) would either have a lot of effect from say, glycine or about the same relative effect as his average/low protein friend because other proteins activate a generalized process of deamination which reduces glycine levels in the body. what gives?

  • Chris

    Excellent job!

  • Harry W

    Hi Joe

    Is inhibiting stomach acid secretion a good thing? I thought it would be harmful.

    Isn’t it accepted (outside conventional medicine) that GERD is caused by too little, not too much, acid secretion?

    Or is it more complex?

  • Thomas Kelly

    Love, love, love your content joe! Great job as always…
    All the best- Tom

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