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    What is GlyNAC? Benefits, Dosage and Risks

    What is GlyNAC? Benefits, Dosage and Risks
    October 30, 2023 Vitality Pro

    What is GlyNAC? Benefits, Dosage and Risks

    GlyNAC is an amino acid supplement that combines Glycine with N-Acetyl-L-Cysteine (NAC) to offer a range of benefits for human health. NAC and glycine are both non-essential amino acids that are found in a variety of food sources and are also produced naturally within the body. In certain cases, including instances of chronic disease and age-related degeneration, the body fails to produce sufficient amounts of NAC from L-cysteine sources. It is for this reason that some longevity experts consider NAC to be an essential amino acid in its own right – albeit a conditional one.

    When taken in supplement form, GlyNAC is believed to address and reduce the symptoms associated with certain disorders and diseases, including:

    • Chronic inflammatory disorders
    • Mitochondrial dysfunction
    • Metabolic disorders
    • Cognitive decline

    It can also be used to: 

    • Reduce the incidence of acne
    • Detoxify the body from heavy metals
    • Treat certain mental health conditions like depression
    • Promote better quality sleep

    In this guide, we will explore the primary health benefits of GlyNAC supplementation, share optimal dosages and potential side effects, and highlight scientific evidence of the supplement’s ability to support a variety of physical processes critical to health and wellness.

    GlyNAC Benefits

    • Optimising mitochondrial function
    • Reducing oxidative stress via glutathione production
    • Reducing insulin resistance and type II diabetes risk
    • Limiting and reducing gene damage and toxicity
    • Improving cognitive function and addressing the symptoms of depression
    • Enhancing heart health
    • Expanding both life span and health span
    • Limiting the progression of age-related diseases and physical and cognitive decline

    GlyNAC Risks

    • Nausea
    • Skin rashes
    • Fatigue
    • Vomiting
    • Eye irritation
    • Diarrhoea
    • Low blood pressure
    • Headaches

    How Does GlyNAC Work?

    The natural process of ageing is associated with increases in both mitochondrial dysfunction and free radicals. Both of these factors contribute to accelerated ageing and the onset of age-related diseases, including chronic inflammation, metabolic disorder, type II diabetes, loss of muscular strength, dementia, cardiovascular disease, and others.

    One of the compounds which address both mitochondrial dysfunction and the oxidative stress caused by high free radical concentrations is glutathione. This antioxidant compound is produced in the human body, and its production declines with advanced age. GlyNAC contains both cysteine and glycine; two amino acids which also decline with age and are required for optimal glutathione production. 

    One research study notes that glutathione production increased by up to 231% when senior adults were administered supplemental glycine and cysteine. Oxidative stress and free radical damage were also hindered in these patients. The research notes that by supplying the body with the precursor amino acids needed to produce glutathione, it is possible to slow the progression and onset of many age-related diseases which would otherwise impact both life span and health span.

    The Importance of Taking Glycine and NAC Together

    GlyNAC induces different effects to glycine or NAC when the latter two are taken separately. The process of glutathione synthesis requires both glycine and cysteine, provided by NAC, in optimal ratios and cannot be achieved with only one of these amino acids. 

    Supplementing with NAC alone does not provide the body with glycine, which is required for the synthesis of glutathione. This is why it is important to take both amino acids together in the form of GlyNAC to optimise glutathione levels and maximise the health benefits that this offers.

    Potential Health Benefits

    The latest scientific research shows that GlyNAC could have a broad range of potential health benefits for its users, ranging from extending life span and longevity to reducing the risk of cancers, type II diabetes and heart disease, and promoting optimal cognitive function, even in older age.

    It is important to note that further human research is still needed to assess the full spectrum of effects of GlyNAC supplementation on human health and longevity.

    GlyNAC Mitochondrial Research

    Abnormal mitochondrial function is associated with a wide range of health impacts, as mitochondria generate the energy required to support all major cell-level functions. Studies on GlyNAC have discovered that GlyNAC supplementation corrected mitochondrial malfunction in mice. The clinical trial identified that older adults have widespread mitochondrial damage and certain other defects in their cells compared to their younger peers. 

    In a 2021 study with GlyNAC, the mitochondrial function of these older participants improved, becoming similar to the levels found in younger adults. Moreover, the research found that GlyNAC effectively reduced levels of gene damage and cellular senescence, which are associated with the development of malignant cells.

    GlyNAC Ageing Research

    A recent study published in Clinical and Translational Medicine has found that senior adults who took GlyNAC supplements for a period of 24 weeks experienced improvements in many disorders associated with the ageing process. 

    The researchers noted improvements in the participants’ levels of oxidative stress and glutathione deficiency, markers of insulin resistance, inflammation, and mitochondrial dysfunction, endothelial dysfunction markers, and in body fat levels. Improvements were also noted in genomic toxicity markers, gait speed, muscle strength, physical capacity, and cognitive function. 

    GlyNAC supplements were reported to be well tolerated by the study participants, and it was noted that the aforementioned benefits declined when supplementation was paused for a 12-week period. This suggests that ongoing supplementation may be needed to sustain the beneficial effects of GlyNAC for an effective slowing of the ageing process.

    GlyNAC Liver Research

    Research on animal models suggests that GlyNAC supplementation can increase life span while addressing a variety of hallmarks of the ageing process. By optimising glutathione levels in the body, GlyNAC can correct mitophagy abnormalities, mitochondrial and nutrient sensing dysfunctions, genomic toxicity and damage in vital organs, including the liver. 

    Glutathione plays an important role in supporting the liver’s detoxification pathways, positively affecting the entire body as a result of enhanced elimination of metabolic waste products.

    GlyNAC Depression Research

    Initial data supports GlyNAC’s benefits for addressing depression, which is a common symptom of cognitive decline. One group of researchers evaluated a group of older mice to assess their cognitive abilities and compared these results to the abilities of young mice. The older mouse group was split into two. One sub-group was given a diet supplemented with GlyNAC, and the other received a standard diet with no supplementation. 

    After 8 weeks, the mice were analysed again. Researchers noted that, at the start of the study, the older mice showed signs of cognitive impairment and brain abnormality, including increased oxidative stress, mitochondrial dysfunction, glutathione deficiency, gene damage, and reduced levels of brain-supporting factors. Moreover, they identified evidence of a shortage of transportation proteins which move glucose into the brain to be used as fuel.

    GlyNAC supplementation was seen to correct glutathione deficiency in the mice’s brains while increasing the prevalence of brain glucose transporters, addressing mitochondrial dysfunction, and improving overall cognition. The supplements also reduced inflammation, gene damage, and oxidative stress and were noted to improve neurotrophic factors in the test subjects. 

    While more research is needed to determine if these results are replicable in humans, the data does suggest that GlyNAC could play an essential role in supporting brain health and function and reducing the incidence and severity of brain-related disorders like depression. A 2021 pilot trial on humans suggests that similar effects are likely applicable.

    GlyNAC Diabetes Research

    Type II diabetes is a condition characterised by increased body fat, insulin resistance, high levels of circulating blood glucose, and chronic low-grade inflammation. The risk of type II diabetes onset increases with age, and the key to preventing this onset is to maintain optimal insulin signalling and function through a combination of diet and lifestyle factors.

    Clinical research suggests that GlyNAC supplementation could reduce the incidence and severity of type II diabetes by reducing insulin resistance in older adults. A recent study noted that elevated oxidative stress impairs insulin signalling and promotes mitochondrial dysfunction and inflammation – all of which can be improved through the use of GlyNAC. The study also found that GlyNAC supplementation reduced body fat levels; another mechanism which could help to reduce type II diabetes risk and effectively treat active cases.

    Type II diabetes is also associated with low levels of glutathione. Researchers administered glycine and cysteine to 12 patients with uncontrolled type II diabetes for a period of 2 weeks. After the treatment period was over, the researchers noted a 64% average increase in glutathione levels in the patients, as well as a 200% increase in glutathione synthesis. The data suggests that glutathione levels can be restored in diabetic patients, although more research is needed to better understand the implications of these findings for treating this chronic health condition.

    GlyNAC Heart Research

    Another recent publication found that when older mice received GlyNAC supplements, the amino acids improved cardiac mitochondrial energetic factors, reduced cardiac inflammation, and improved cases of diastolic dysfunction. 

    Moreover, research indicates that GlyNAC reduces endothelial dysfunction – a characteristic of cardiovascular disease strongly linked to advanced age and chronic inflammation. The amino acids work by reducing levels of pro‐inflammatory cytokines TNFα, IL6, and CRP to protect endothelial function and cardiac tissue and improve cardiometabolic health.

    GlyNAC Life Extension Research

    A study published by Dr Rajagopal Sekhar, a professor of medicine, endocrinology, diabetes and metabolism at Baylor College of Medicine, has found that GlyNAC supplements induce improvements in a variety of ‘ageing hallmarks’ including:

    • Chronic inflammation
    • Insulin resistance
    • Mitochondrial dysfunction
    • Mitophagy
    • Cellular senescence
    • Gene damage
    • Endothelial dysfunction
    • Glutathione deficiency

    Additionally, the amino acid complex was found to reduce stem cell fatigue. Collectively, these effects led to improvements in gait speeds, exercise capacity, blood pressure readings, waist circumference measurements, and muscle strength in test subjects.

    While these results were derived from animal studies, similar improvements in hallmark characteristics of age-related disease were also found in humans taking GlyNAC supplements. Dr Sekhar noted in his study that GlyNAC supplementation increased the life spans of aged mice by 24% and that gait speed is closely linked with survival in senior humans, indicating that GlyNAC could potentially have implications for improved survival rates in elderly patients.

    Potential Risks and GlyNAC Side Effects

    Human studies on GlyNAC supplementation suggest that the supplement is generally safe and produces few to no significant side effects. However, it is important to start any new supplement with caution. 

    Most experts recommend starting at a lower dose than recommended for the first week of use. This is a practice known as titration which allows the body to adjust to a new supplement over time while minimising potential side effects. Thus, if a recommended dose is 600mg per day, one could start with an initial dose of 300mg and build up towards the full recommended dose over the course of a few days or weeks.

    GlyNAC Drug Interactions

    Stop taking GlyNAC at least 2 weeks before you are due to undergo surgery and be advised that this supplement may interact with certain drugs, including drugs for hypertension and schizophrenia and blood thinning medications. If you are breastfeeding, pregnant, or have any existing medical conditions or take any medications, speak with your doctor before starting a GlyNAC protocol. Take caution with N-Acetyl-Cysteine intravenous infusions. Reports have linked them to liver and kidney failure and in some cases, death. Oral supplements have not been linked to any similar incidences.

    GlyNAC supplements may also cause some mild side effects, including nausea, fatigue, eye irritation, skin rashes, diarrhoea, and more rarely, headaches and low blood pressure. If you experience any of these side effects, stop taking the supplements immediately and consult a healthcare professional for advice.

    Patients undergoing cancer treatments such as radiation therapy or chemotherapy should also consult their doctors before taking GlyNAC. GlyNAC stimulates the production of glutathione, which may reduce the efficacy of certain cancer treatment drugs. More research is needed to gain a clearer understanding of the full range of side effects associated with GlyNAC supplementation.

    Dietary and Natural Sources

    Dietary choices can help to support optimal levels of glycine and cysteine in the body, which in turn facilitate the production of the antioxidant glutathione. The foods that contain the most notable levels of these two amino acids include chicken, beef, beans, fish and spirulina for glycine; and chicken, beef, turkey, onions, eggs, and red bell peppers for cysteine.

    Consuming these foods on a regular basis may help to improve glycine and cysteine levels, supporting optimal production of glutathione and the full range of benefits it offers. Although diet and lifestyle changes can help to fortify the body with critical vitamins and minerals, certain compounds are challenging to consume in therapeutic quantities. 

    This is why a GlyNAC supplement is likely the best way to benefit from the therapeutic effects of glycine and N-Acetyl-L-Cysteine. More research and human trials are needed to determine the most effective ways of promoting and maintaining optimal glutathione production. 

    Supplements and Optimal Dosages

    Most studies on the use of GlyNAC administer around 1.33mmol per kg of body weight per day of glycine and around 0.81mmol per kg of cysteine in each daily dose. For a person weighing roughly 150lb (68 KGs), the dosage used would be around 9g of NAC and 7g of glycine per day. More research is needed to determine the optimal dosage, and this dosage will also depend on the reasons for which GlyNAC is being administered. However, many experts recommend a 600mg daily dose as a strong initial dosage, as cysteine and glycine are both already produced by the human body.

    According to Medical News Today, 600mg-1,200mg is the most commonly recommended dosage of GlyNAC by medical practitioners. If you are planning on supplementing with GlyNAC, be sure to discuss your plans with a qualified medical professional to find the right dosage for you. Supplementation is not recommended for children under the age of 12.

    Certain brands also offer GlyNAC eye drops. However, it should be noted that the NAC contained in these products is N-acetylcarnitine and not N-cetyl-L-Cysteine, and should not be confused. GlyNAC eye drops will not have the same effects or benefits as GlyNAC taken in capsule form.


    Taking a GlyNAC supplement can help to address glycine and cysteine deficiencies, which are common in older adults. Optimising these amino acid levels in the body can support improved production of glutathione, a powerful antioxidant compound that may slow the onset and progression of many age-related conditions. 

    Research shows that GlyNAC may also be able to treat cancer, type II diabetes and depression, improve longevity, and enhance cognitive function. Although further research is needed to understand exactly how these effects are achieved.

    Anyone who is interested in starting a GlyNAC supplement regime should consult with a medical or healthcare professional to determine whether or not GlyNAC is the best choice for their needs.


    Where can I buy GlyNAC?

    GlyNAC supplements are available from trusted providers like Vitality Pro. They can be purchased online, or you can find them at a physical store. Be sure to choose high quality, clinically tested supplements like those offered by Vitality Pto for best results.

    What is the best GlyNAC supplement?

    The best supplement is one that provides at least 600mg of glycine and N-Acetyl-L-Cysteine and has been clinically tested for efficacy, purity and safety.

    Is GlyNAC safe?

    GlyNAC supplements are generally considered to be safe as long as the recommended dosages are adhered to. Some people experience mild side effects during supplementation; if you experience any unwanted effects, speak to your doctor as soon as possible.

    What is the ideal GlyNAC supplement dosage?

    While more research is needed, most experts recommend starting at a daily dose of 600mg.

    What are the leading GlyNAC benefits?

    GlyNAC has been shown in studies to reduce inflammation and insulin resistance, support liver function, promote cardiovascular health, slow the progression of ageing and age-related diseases, and improve mitochondrial function.

    What is GlyNAC good for?

    GlyNAC can be used to treat age-related cognitive and physical decline, depression, type II diabetes, cardiovascular disease, and low energy levels caused by mitochondrial dysfunction. 

    GlyNAC vs NAC, which is best?

    N-acetylcysteine (NAC) is a supplemental form of the amino acid cysteine and is used alone to improve levels of cysteine in the body and to treat deficiencies in this compound. GlyNAC is a lab-engineered combination of both glycine and NAC. 

    Most studies on health, longevity and ageing have used a combination of glycine and NAC (GlyNAC) to achieve beneficial effects on age-related disease and their treatment outcomes. For this reason, it is recommendable to take GlyNAC if you are looking to achieve specific health outcomes for which the supplement is indicated.

    GlyNAC vs Glutathione

    GlyNAC supplementation is often referred to as glutathione supplementation, although a distinction should be made as to the exact contents of the supplement in question. 

    GlyNAC does not contain glutathione in and of itself, but it does supply both glycine and cysteine, which support the body’s natural production of the antioxidant glutathione.

    If you have a genetic polymorphism that indicates you lack the required genetics to create glutathione you may be better served with a Liposomal Glutathione supplement. 

    Glossary of Technical Terms 

    Cellular senescence: A phenomenon whereby cells stop dividing.

    Genomic toxicity: Accumulated damage of the genetic material inside cells which increased the risk of cell mutations and tumour formation.

    Glutathione: A tripeptide antioxidant that limits oxidative stress in cells.

    Mitochondrial dysfunction: Sub-optimal function of the mitochondria which leads to reduced energy production and the acceleration of age-related disease onset and progression.

    Mitophagy: The process of mitochondrial degradation through autophagy, or the planned destruction of cells.

    Neurotrophic factors: Any neuro-peptides that have the ability to regulate the survival, development, and differentiation of neurons.

    Oxidative stress: A condition caused by an imbalance of antioxidants and free radicals in the body which leads to accelerations in cell damage and ageing.