Glutathione supplements: is it absorbed, is liposomal better, and why skin-whitening drips are risky

What glutathione is and what it does

Glutathione is a small molecule built from three amino acids: glutamate, cysteine and glycine. It’s found in almost every cell. It neutralises reactive oxygen species and helps the liver clear medicines and toxins.

Your body makes glutathione itself, so there’s no recommended daily intake and no dietary deficiency. Levels drop with paracetamol poisoning, cirrhosis, alcohol misuse and HIV infection, but those are matters for a doctor, not a supplement.

People usually buy glutathione:

• for “antioxidant support” or a “detox”;
• to lighten their skin or even out its tone;
• as a cheaper alternative to drips offered by aesthetic clinics.

For each of these, the evidence is weaker than the marketing. The US National Center for Complementary and Integrative Health (NCCIH) notes that antioxidant supplements in general haven’t been shown to prevent heart disease or cancer.

Is oral glutathione absorbed?

For years the answer was no. An enzyme in the gut and liver, gamma-glutamyl transferase, breaks glutathione down. In a 1992 study, 7 healthy volunteers swallowed about 3 g in one go. Over the next 4.5 hours, blood glutathione didn’t rise significantly.

Taking it daily gave different results, though not in every trial:

• 4 weeks, 40 adults (2011). 500 mg twice a day changed neither red blood cell glutathione nor markers of oxidative stress.
• 6 months, 54 adults (2015). At 1,000 mg a day, glutathione rose by 30–35% in red cells, plasma and lymphocytes. At 250 mg, it rose by 17% in whole blood and 29% in red cells. A month after stopping, levels were back to baseline.

It looks as if daily glutathione does raise blood levels, slowly, and only while you keep taking it. Whether that improves health hasn’t been tested.

Liposomal glutathione: worth paying more?

A liposome is a microscopic bubble made of phospholipids. In theory, the coating protects glutathione from being broken down in the gut. Liposomal glutathione usually comes as a liquid in a pump bottle and costs noticeably more than capsules.

The main human evidence is a single pilot study from 2018. Twelve healthy adults took 500 or 1,000 mg of liposomal glutathione for a month. After 2 weeks, whole blood levels had risen by up to 40%. But there was no placebo group and no comparison with standard capsules. A company selling liposomal glutathione funded the work.

So the claim that liposomal glutathione is “better absorbed” hasn’t been shown.

NAC: the glutathione precursor

Cells are limited mainly by cysteine when they make glutathione. N-acetylcysteine (NAC) supplies that cysteine. That’s why NAC is often described as a more reliable way to support glutathione than swallowing glutathione itself.

NAC has one clear advantage: it’s an established medicine, used for paracetamol overdose and to loosen thick mucus. But in a healthy person whose glutathione isn’t depleted, extra NAC hasn’t been shown to help either. Our guide to the NAC supplement covers the details.

Alpha lipoic acid is also marketed as a way to “recycle glutathione”. It’s the same story: a plausible mechanism, no proven benefit for healthy people.

Glutathione skin whitening: what the trials show

Glutathione slows the enzyme tyrosinase and shifts pigment production from dark melanin to a lighter type. That’s why it’s popular for skin lightening in parts of Asia.

What trials of tablets found:

• 500 mg a day for 4 weeks, 60 students (Thailand). The melanin index fell at all 6 skin sites, but differed significantly from placebo at only 2: the face and a forearm.
• 250 mg a day for 12 weeks, women (Thailand). Melanin index was lower than with placebo, but mostly as a trend.
• A 2025 systematic review. Five randomised trials of 250–500 mg tablets showed lower melanin index scores. Its authors describe the effect as moderate and not sustained after stopping.

Long-term safety hasn’t been studied. The Philippine FDA also mentions a theoretical skin cancer risk: dark melanin protects against the sun, and glutathione reduces how much you make.

For pigmentation and an even tone, daily sunscreen and advice from a dermatologist will do more. What else may help your skin from the inside is covered in our guide to supplements for skin.

Glutathione injections and drips: regulator warnings

Some salons and clinics offer intravenous glutathione for “whitening”. Regulators oppose it:

• Philippine FDA (2019). Injectable glutathione is approved there only as an add-on to cisplatin chemotherapy. There are no trials for skin lightening and no established dose or course length. It lists liver, kidney and nervous system toxicity, Stevens-Johnson syndrome, a theoretical skin cancer risk, and HIV and hepatitis B and C from non-sterile procedures.
• US FDA (27 August 2026). At least 30 patients had fever, chills, pain, dizziness and signs of shock or sepsis after IV glutathione, and some were admitted to hospital. Compounding pharmacies had made the drips from glutathione labelled as dietary supplement grade, and two pharmacies in Texas recalled products over high endotoxin (bacterial toxin) levels.
• The 2025 review. Intravenous glutathione is contraindicated: there’s no proof it works, and it has side effects.

If you develop fever, chills or dizziness after any infusion, seek urgent medical help.

How to take glutathione

There’s no official dose. These are the amounts used in research:

• Start with 250 mg: in the 6-month trial, that dose also raised blood levels.
• Judge the result after 1–3 months, not after a week.
• If you’re also taking vitamin C or collagen for your skin, start products one at a time so you can tell what’s doing what.

Who should avoid glutathione, and interactions

• Pregnancy and breastfeeding. There are no safety data, so avoid it.
• Asthma. Nebulised glutathione caused bronchospasm in people with mild asthma. There’s no such data for tablets, but avoid inhaled forms.
• Chemotherapy and radiotherapy. NCCIH warns that antioxidants might make these treatments less effective. Only with your oncologist’s agreement.
• Children. Don’t give it unless a doctor recommends it.

If you take regular medicines, check combinations in our vitamin compatibility chart and ask a pharmacist.

How to choose glutathione on iHerb

1. Decide why you want it. If it’s “just in case”, you may not need it; our vitamin check can help.
2. Pick the form: reduced glutathione (GSH) capsules as the default; liposomal only if you’re happy to pay more for an unproven edge.
3. Check the dose per capsule: 250 or 500 mg is easy to work with.
4. Compare the price per 250 mg, not per bottle: a big tub of low-dose capsules can easily work out dearer.
5. Look for independent quality testing (USP, NSF and similar seals).

Our guide to reading a supplement label explains the Supplement Facts panel. More options for skin and hair are in our skin, hair and joints section.