bowl of veggies
Glutathione, often referred to as “the mother of all antioxidants,” is one of the most talked-about supplements in the healthcare industry…and for good reason. Glutathione is produced and used by every single cell in the human body and, therefore, has a very wide range of scientifically-proven health effects.
In this article we will explore the science surrounding the biological benefits of glutathione supplementation, and the best measures you can take to ensure your glutathione levels are optimally balanced.
What Is Glutathione?
Glutathione is a peptide containing 3 important amino acids that have several important roles in the human body [R].
Glutathione is an important antioxidant in animals, plants (especially avocados), fungi, and some bacteria, where it prevents damage to important cellular components caused by reactive oxygen species [R].
By removing oxygen radicals from the body, glutathione protects many different body systems from disease and deterioration [R].
Glutathione is a defensive agent against the action of toxic xenobiotics (drugs, pollutants, carcinogens) [R].
Because of its wide range of uses in the body, it is essential to prevent glutathione levels from becoming low.
Glutathione deficiency manifests in increased susceptibility to oxidative stress, the resulting damage of which is thought to be involved in a plethora of diseases, such as cancer, Parkinson’s, and Alzheimer’s disease [R].
- Great antioxidant
- Good detoxifier
- Positive effects for prevention of glaucoma and cataracts
- Helps liver function
- Promising for a variety of conditions
- Tastes really bad
- Absorption and bioavailability is poor unless taken in liposomal form
- If health is very poor, must start slow and work to a higher dose
Health Benefits of Glutathione
1) Glutathione Fights Oxidative Stress in the Body
Glutathione reduces the amount of reactive oxygen species (ROS) and oxidative stress in the body, which would otherwise cause damage to cells and DNA [R, R, R].
2) Glutathione May Control Inflammation
Glutathione inhibits the production of most inflammatory cytokines [R].
A number of pulmonary diseases are caused by excessive inflammation. In many of these diseases, restoring glutathione to a healthy level is protective, indirectly supporting the idea that glutathione is anti-inflammatory [R].
3) Glutathione Is Anti-Aging
With less glutathione, free radicals can harm the body and cause aging [R].
Replenishing glutathione levels may slow the aging process [R].
Imbalances in glutathione levels affect immune system function and are thought to play a role in the aging process [R].
Multiple studies have demonstrated that the body makes less glutathione as it ages [R].
Glutathione drops off during menopause, which may be part of the reason for the dramatic aging that occurs during this time in a woman’s life.
By maintaining glutathione levels, aging individuals may prevent age-related cognitive decline [R].
Myricitrin, a drug used in preventing age-related osteoporosis, may work by increasing levels of glutathione [R].
4) Glutathione May Prevent Depression and Stress
Also, glutathione is able to prevent shock-induced behavioral depression in animals [R].
A study on mice showed that alprazolam, a drug used to relieve stress, increased levels of glutathione in the mice [R].
5) Glutathione May Limit Neurodegeneration
The cells of the human brain consume about 20% of the oxygen utilized by the body but make up only 2% of the body’s weight. Reactive oxygen species are continuously generated during oxidative metabolism. Therefore, the detoxification of reactive oxygen species is an essential task within the brain. Glutathione plays a key role in this process [R].
Alzheimer’s disease is in part caused by the oxidative stress that antioxidants neutralize, as demonstrated by clinical studies showing that oral vitamin E (powerful antioxidant) intake slowed the progression of Alzheimer’s [R].
To make matters worse, Alzheimer’s is characterized by an accumulation of TDP-43 (a DNA binding protein) in the nervous system, which further lowers glutathione levels [R].
In mice, a protein that increases glutathione levels in the body was found to increase memory in subjects with Alzheimer’s [R].
Parkinson’s disease involves the loss of dopaminergic neurons in the substantia nigra part of the brain. Studies have noted that people in pre-clinical stages of Parkinson’s have low glutathione levels in the substantia nigra [R].
A study showed that a drug, named 3,4-dihydroxy benzalacetone, helped prevent Parkinson’s disease by increasing levels of glutathione [R].
6) Glutathione May Help with Infections
Patients with tuberculosis have been shown to have low glutathione levels [R].
Another study showed that the maintenance of cysteine levels, and thus glutathione levels, is important for enhancing mycobacterial killing activity [R].
7) Glutathione May Heal the Gut
Glutathione peroxidase is an important enzyme for the normal renewal of the gut wall [R].
Glutathione protects the intestinal mucosa. Administration of glutathione may protect the gut wall which, when weakened, can lead to leaky gut (R).
8) Glutathione May Treat Autism
Other abnormalities have been found in the transsulfuration pathway (the pathway where glutathione is produced) in children diagnosed with autism [R].
Oral and transdermal glutathione are currently being used to normalize glutathione levels in autistic children. Early studies indicate that this may improve some of the transsulfuration metabolites often low in autistic children [R].
9) Glutathione and Cancer
Glutathione is a major factor in the regulation of life, proliferation, and death of cancer cells [R].
There is significant correlation between increased glutathione intake and decreased risk of oral and throat cancer [R].
Furthermore, glutathione plays a key role in repairing damage done by cancer drugs on cells in chemotherapy patients [R].
Glutathione is crucial in the removal and detoxification of carcinogens. However, it should be noted that, by conferring resistance to a number of chemotherapeutic drugs, elevated levels of glutathione can actually protect tumor cells. Perfect balance is imperative [R, R].
10) Glutathione May Treat Psychiatric Disorders
High levels of free radicals were found in the blood of patients with OCD. Reducing these levels by introducing glutathione may help reduce the severity of OCD symptoms [R].
Furthermore, glutathione may help to reduce stress, which is a major symptom and possibly a contributing factor of OCD [R].
Multiple drugs used to treat bipolar disorder work by increasing glutathione levels [R].
11) Increasing Glutathione Levels May Help ADHD
Pycnogenol, a glutathione booster, was found to normalize antioxidant levels in children with ADHD [R].
12) Glutathione May Help in Preventing Heart Disease
Cardiovascular disease is largely caused by oxidative stress in heart tissues. Perhaps this is why insulin resistance, impaired glucose tolerance, and diabetes (3 conditions that cause oxidative stress), are linked to heart attacks [R, R].
13) Glutathione May Treat Diabetic Complications
Diabetes II and high blood sugar cause the reduction of glutathione in the body [R].
Studies show introducing extra glutathione into the body prevents or limits these complications [R].
14) Glutathione May Prevent Kidney Disease
Oxidative stress in the kidneys can cause kidney failure [R].
A study, which investigated 20 patients suffering from chronic renal failure and undergoing hemodialysis, found that supplemental glutathione resulted in a marked improvement in kidney function (as measured by red blood cells, plasma reduced glutathione, hematocrit, and hemoglobin) [R].
15) Glutathione Protects Against Liver Damage
The liver upregulates glutathione synthesis to combat the effects of a high-fat diet.
16) Glutathione May Help Prevent Addiction
These species can alter proteins involved in neuronal and behavioral pathways, causing the subject to become addicted. By reducing the presence of these reactive species, glutathione may decrease the development of addictive behaviors [R, R].
This may also be applicable to overeating disorders [R].
17) Glutathione May Reduce Consequences of Drugs or Alcohol
Chronic alcohol use causes oxidative stress and reduces liver levels of glutathione [R].
Glutathione improved the liver function of alcoholics, but only when they abstained from alcohol use.
18) Glutathione Controls Cell Death
Glutathione depletion is a key signalling event that controls the activation of cell death pathways. For example, S-glutathionylation in important for protein modulation and apoptotic (cell death) initiation [R, R].
Cells depleted of glutathione are susceptible to damage, especially from arachidonic acid. Studies show that low glutathione levels cause a series of events, which ultimately result in cell death [R].
19) Glutathione Can Help with Respiratory Issues
The same study showed that increasing levels of glutathione decreased inflammation and reduced asthma in the airway [R].
Chronic Obstructive Pulmonary Disease (COPD) is a lung disease caused by long-term oxidative damage to lung tissue, the damage of which results in inflammation of the lung tissue, causing shortness of breath and coughing [R].
Glutathione supplements can decrease this oxidative damage and tissue damage within the lungs , thereby reducing the risk of developing COPD [R].
20) Glutathione Can Treat Sleep Apnea
A study showed that glutathione levels were low in subjects who were diagnosed with sleep apnea, and that increasing those levels of glutathione to normal improved sleep quality in these patients [R].
21) Glutathione May Treat Acne
A decline in antioxidative activity, especially a decrease in glutathione quantity, may play a key role in the development of acne [R].
Increasing glutathione levels may help reduce acne by decreasing oxidative stress levels.
22) Glutathione May Help Treat Rheumatoid Arthritis
Patients with rheumatoid arthritis have increased levels of glutathione peroxidase as a response to high levels of oxidative stress. It makes sense to supplement glutathione to ensure that these individuals can match this high demand for glutathione [R].
23) Glutathione Helps Prevent Glaucoma and Cataracts
24) Glutathione Encourages a Healthy Pregnancy
In pregnant women, low glutathione levels caused by depression may lead to impaired brain development in the unborn child [R].
Increased amounts of reactive oxygen species in a fetus have been linked to preterm labor. Thus, by reducing these oxygen species, glutathione can delay the onset of labor to a biologically healthier time [R].
25) Glutathione May Treat AIDS
Glutathione deficiency weakens the immune systems of AIDS patients with already weak bodies. Studies have shown that giving these individuals additional glutathione can rebalance their immune systems [R].
26) Glutathione May Treat Cystic Fibrosis
Cystic fibrosis causes the release of oxidative reactants in to inflammatory cells. Making matters worse, cystic fibrosis reduces levels of glutathione able to scavenge these reactants [R].
Glutathione inhalers can restore oxidant-antioxidant balance and reduce inflammation in those with cystic fibrosis [R].
More broadly, certain forms of buffered glutathione have been found to lower the symptoms of cystic fibrosis [R].
27) Glutathione Is a Skin Lightening Agent
This is because glutathione causes the production of a different type of melanin in skin cells [R].
Glutathione Metabolism and Administration
Glutathione is made in the body from 3 amino acids: glutamate, cysteine, and glycine (making it a “tripeptide”). The glutathione produced in the body is broken down by an enzyme, GGT, on the surface of the cells before it can be transported to the inside of the cell [R]
However, when we ingest glutathione as a supplement, it has to pass the liver before it reaches the bloodstream. The liver can contain high amounts of GGT, which can break down glutathione. This means that most oral forms of glutathione may not achieve the desired effects [R].
There are several ways to bypass this limitation, such as [R]:
- Liposomal glutathione [R]
- Sublingual glutathione (absorbed directly into the bloodstream) [R]
- Slow-release tablets dissolved in the mouth (orobuccal) or lozenges [R, R]
- Inhaled glutathione [R]
- Methyl glutathione, where another compound (the methyl group) is attached to glutathione, so GGT cannot degrade it [R]
- Coated glutathione tablets [R]
- IV glutathione is also available, but the safety has not been established [R]
New formulations of glutathione are being researched every day in the hopes of maximizing its concentration in the body.
People with asthma should not inhale glutathione.
Taking glutathione supplements during pregnancy or breastfeeding is not recommended.
Thirty-eight participants aged 21 to 62 were given oral glutathione (1,000mg a day) for 4 weeks. Side effects were limited, but included: Increased flatulence and loose stools (5 patients), flushing (2 patients), and weight gain (1 patient) [R].
Another study that gave glutathione to patients with cystic fibrosis found the following side effects: Chest tightness, diarrhea and fever. Of course, these results may not apply to the general population [R].
Also, these studies are relative exceptions; to date, glutathione supplements are known as safe. More research is undoubtedly needed on high-dose and long-term glutathione supplementation.
Glutathione Side Effects (If You Have Chronic Inflammation)
When studies deplete glutathione, it reduces the inflammatory response, because it reduces the immune system response [R].
However, under inflammatory conditions, it often becomes more important to reduce the damage with an antioxidant like glutathione.
So glutathione can both be good and bad if someone has chronic inflammation. If you get negative side effects, it could be that it’s stimulating your immune system too much.
Glutathione in Food
The picture above shows a number of foods that contain glutathione precursors. These are great additions to your diet, but I usually recommend supplementation to get a therapeutic and reliable dose.
Garlic, asparagus, and cruciferous vegetables such as broccoli and kale boost glutathione levels as a result of their sulfur components.
Increasing Glutathione with Supplements
Out of three amino acids that glutathione is made from, cysteine is the most important; the amount of cysteine governs the speed and quantity of glutathione that can be made inside the cell. Here are some options for increasing cysteine:
NAC – dose usually 500 to 1,000mg/day
Selenium is important for maintaining healthy glutathione levels as it becomes a component of glutathione peroxidase in the body – the enzyme that helps neutralize free radicals.
Alpha Lipoic Acid (ALA)
S-adenosyl-methionine is a supplement that contains methionine and can help boost glutathione levels.