The Complete Guide to Glutathione: Benefits, Dosage, and Safety

What Is Glutathione?

Glutathione is described by Healthylife as the “master antioxidant” and is produced by every cell of the body. Healthylife explains it is a tripeptide made up of the amino acids glycine, glutamic acid and cysteine, and because the body can form it from these amino acids, it is not considered an essential dietary nutrient.

Naturecan similarly describes glutathione as a naturally occurring tripeptide molecule composed of cysteine, glutamic acid and glycine, present in nearly all cells of the human body, and notes it can also be found in foods (including fruits, vegetables and meats).

Sources: Healthylife, Naturecan AU

How Glutathione Works in the Body

Healthylife lists multiple roles for glutathione inside cells, including: supporting cellular metabolism and energy production, acting as a cofactor for enzymes such as glutathione peroxidase, supporting inflammation signalling, promoting immune function, regenerating antioxidants such as vitamins C and E, participating in liver detoxification pathways, transporting heavy metals (such as mercury) out of cells, and maintaining and protecting mitochondria for energy production.

Healthylife also explains glutathione exists in two states inside cells: reduced (GSH) and oxidised (GSSG), and describes the GSH:GSSG ratio as an indicator of cellular oxidative stress (higher ratios indicating healthier cells, while lower ratios are associated with heavy oxidative stress).

Source: Healthylife

Key Benefits: What the Evidence Says

Important: The sections below summarise what the sources report. If a source does not provide a clear evidence grade or outcome detail, it is marked accordingly.

Antioxidant activity and “master antioxidant” positioning

Healthylife describes glutathione as the “master antioxidant” and lists its roles in regenerating antioxidants such as vitamins C and E, supporting mitochondria, and functioning as a cofactor for glutathione peroxidase (an antioxidant enzyme). An iHerb AU product page (Jarrow) describes glutathione as an abundant intracellular tripeptide serving as an antioxidant in tissues and notes its antioxidant functions include recycling vitamins C and E back to their antioxidant form to minimise oxidative stress.

Sources: Healthylife, iHerb AU (Jarrow)

Detoxification support (liver and heavy metals)

Healthylife states glutathione is a major player in liver detoxification and is involved in multiple reactions within phase II detox pathways. Healthylife describes reduced glutathione (GSH) as conjugating with toxins, drugs and metabolic by-products in the liver, rendering them harmless and then escorting them out of the body via bile and elimination pathways. Healthylife also describes glutathione’s roles in protecting against heavy metal damage (including binding and facilitating excretion, and increasing antioxidant capacity to defend against free radical damage associated with heavy metals).

Source: Healthylife

Immune function support

Healthylife states the immune system needs glutathione to function properly and describes it as required for growth and function of white blood cells, including “presentation” of pathogens to the immune system. Healthylife also notes low glutathione levels are associated with susceptibility to infection and multiple conditions (as discussed on that page), and gives an example that increasing glutathione levels has been shown to improve lung capacity and breathing quality in patients with pulmonary fibrosis (as stated on that page).

Source: Healthylife

Healthy ageing and skin outcomes (as reported by Healthylife)

Healthylife discusses ageing in the context of oxidative stress and states glutathione can protect against oxidative damage to cellular components. Healthylife also reports that a 2017 study found that taking 500 mg of supplemental glutathione per day for 12 weeks improved skin quality and significantly reduced wrinkles in healthy women (as reported on that page).

Source: Healthylife

What the evidence does not show (caution statements)

Healthylife summarises a systematic review/meta-analysis reporting that children with autism spectrum disorders were more likely to have altered glutathione markers, but explicitly notes that these findings do not indicate glutathione is an effective “treatment” for autism spectrum disorders.

Source: Healthylife

Who Might Benefit Most

• People focused on antioxidant support: Healthylife and iHerb product information describe glutathione’s antioxidant roles and interactions with vitamins C and E.
• People interested in liver detoxification concepts: Healthylife discusses glutathione’s involvement in phase II detox pathways and conjugation in the liver.
• People looking at skin/ageing claims: Healthylife reports a 12-week study using 500 mg/day for skin quality and wrinkles.

Specific populations who should (or should not) use glutathione for defined clinical conditions: Not specified on the source page.

Sources: Healthylife, iHerb AU (Jarrow)

Recommended Dosage and How to Take It

A single evidence-based “best dose” for all outcomes: Not specified on the source page.

Evidence example (skin/ageing, as reported by Healthylife): 500 mg per day for 12 weeks in healthy women (as reported on the Healthylife page).

Label examples (product directions):

• California Gold Nutrition L-Glutathione (Reduced) 500 mg (iHerb AU): Suggested use: Take 1 capsule daily, with food (as stated on the iHerb page).
• Jarrow Formulas Vegan Glutathione Reduced 500 mg (iHerb AU): Suggested use: Adults take 1 capsule once a day with a meal, or as directed by a qualified healthcare professional (as stated on the iHerb page).
• Naturecan AU Glutathione Capsules: Recommended use: 1 capsule daily with a glass of water (as stated on the Naturecan page). Naturecan lists 100 mg L-Glutathione per daily serving on its nutritional information (as presented on that page).

Sources: Healthylife, iHerb AU (California Gold Nutrition), iHerb AU (Jarrow), Naturecan AU

Best Time to Take Glutathione (Timing and With/Without Food)

Best time of day (morning vs evening): Not specified on the source page.

With or without food depends on the product. The iHerb AU listings referenced above suggest taking glutathione with food/with a meal. Naturecan recommends taking its capsule with water and does not specify a meal requirement on the section quoted above.

Sources: iHerb AU (California Gold Nutrition), iHerb AU (Jarrow), Naturecan AU

Forms and Quality: What to Look For on the Label

Reduced vs oxidised glutathione: Healthylife explains glutathione exists inside cells as reduced (GSH) and oxidised (GSSG) and discusses the GSH:GSSG ratio as an indicator of cellular oxidative stress.

“Reduced glutathione” on labels: The referenced iHerb AU products specify glutathione (reduced) and list 500 mg per capsule on their supplement facts (as shown on those pages).

Manufacturing/testing claims: Naturecan states its products undergo rigorous testing practices with third parties to ensure product quality, customer safety and supply chain transparency (as stated on its product page). Product-to-product testing comparisons across multiple Australian brands: Not specified on the source page.

Sources: Healthylife, Naturecan AU, iHerb AU (California Gold Nutrition), iHerb AU (Jarrow)

Side Effects and Who Should Avoid It

Specific side effects rates and common adverse events for oral glutathione: Not specified on the source page.

Product warnings on iHerb AU pages advise consulting a healthcare professional before use if pregnant or nursing, under 18, taking medication, or if you have a medical condition (warnings vary by product page). Naturecan states glutathione capsules are generally considered safe for most people when taken as directed, but recommends consulting a healthcare professional before starting any new supplement, especially with medical conditions or when taking other medications.

Sources: Naturecan AU, iHerb AU (California Gold Nutrition), iHerb AU (Jarrow)

Drug and Supplement Interactions

Naturecan advises that certain medications and supplements may interact with glutathione, potentially affecting efficacy or causing adverse reactions, and recommends consulting a healthcare professional before combining glutathione with other medicines or supplements.

A detailed list of specific medication interactions and contraindications: Not specified on the source page.

Source: Naturecan AU

FAQs

Is glutathione an essential nutrient I must get from food?

Healthylife states glutathione can be formed from amino acids (glycine, glutamic acid and cysteine), so it is not considered an essential dietary nutrient; it is produced within cells.

Source: Healthylife

What does “reduced glutathione” mean on a supplement label?

Healthylife describes glutathione as existing in two cellular states: reduced (GSH) and oxidised (GSSG). Several iHerb AU products list “glutathione (reduced)” in their supplement facts, indicating the reduced form on the label.

Sources: Healthylife, iHerb AU (California Gold Nutrition)

Do dietary sources of glutathione work the same as supplements?

Healthylife states that dietary sources of glutathione are “not much help,” saying naturally occurring glutathione is not well absorbed during human digestion (as stated on that page). Naturecan’s product page describes oral capsules as being absorbed into the bloodstream and distributed throughout the body (as stated on that page). These are different statements; comparative absorption outcomes across multiple human studies: Not specified on the source page.

Sources: Healthylife, Naturecan AU

What dose should I take?

A universal best dose for all goals: Not specified on the source page. Healthylife reports a study using 500 mg/day for 12 weeks for skin quality/wrinkles, while product labels vary (for example, some iHerb products suggest 1 capsule daily, and Naturecan suggests 1 capsule daily providing 100 mg per daily serving on its label).

Sources: Healthylife, Naturecan AU, iHerb AU (California Gold Nutrition)

Are glutathione supplements available in Australia without prescription?

Healthylife states that glutathione supplements are currently only available in Australia by prescription (as stated on that page). Current regulatory status by product type, and how this applies across all brands and retailers: Not specified on the source page.

Source: Healthylife

Optional: Shop Glutathione

[Browse Glutathione on iHerb AU: https://au.iherb.com/search?kw=glutathione]

[Naturecan AU Glutathione Capsules: https://www.naturecan.com.au/products/glutathione-capsules]

Disclaimer: This article is general information only and is not medical advice. If you are pregnant or breastfeeding, under 18, have a medical condition, or take prescription medication, speak with your GP or pharmacist before starting supplements.

Sources (allowed domains only): Healthylife (Glutathione – The Master Antioxidant), Naturecan AU (Glutathione Capsules), iHerb AU (California Gold Nutrition L-Glutathione Reduced 500 mg), iHerb AU (Jarrow Formulas Vegan Glutathione Reduced 500 mg)