Glutathione
Your body's master antioxidant. It protects every cell from oxidative damage, supports detox, and declines with age. Here's how to test it and raise your levels.
Glutathione (GSH) is a tripeptide your body makes from three amino acids: cysteine, glycine, and glutamate. It's found in every cell and is your primary defence against oxidative stress, toxins, and heavy metals. Levels decline about 10% per decade after age 20.
What is the glutathione test?
Glutathione exists in two forms: reduced (GSH) — the active, protective form — and oxidised (GSSG) — the spent form. The ratio between these two tells you how well your antioxidant system is keeping up with oxidative stress.
Think of it like a fire brigade. GSH is the water you have ready to fight fires. GSSG is the water that's already been used. If your GSSG is rising relative to GSH, it means your body is under more oxidative stress than it can handle.
This isn't a test most doctors order routinely, but it's increasingly popular in longevity and functional medicine circles because glutathione depletion is one of the most consistent hallmarks of aging.
What your number means
Whole blood GSH is typically 200–300 µmol/L. The GSH/GSSG ratio is more informative — a healthy ratio is above 100:1. As oxidative stress increases, this ratio drops. Below 10:1 suggests significant oxidative burden.
- High GSH, high ratio — your antioxidant system is working well
- Low GSH, low ratio — oxidative stress is outpacing your defences; common in chronic disease, aging, high pollution exposure
- Normal GSH, low ratio — you're producing enough but using it faster than you can recycle it
How to raise your glutathione
NAC (N-acetyl cysteine) 600–1200 mg/day — provides the rate-limiting amino acid cysteine, which your body uses to make glutathione.
This is more cost-effective and better studied than taking glutathione directly.
- Glycine — the other building block; 3–5 g/day, especially effective when combined with NAC
- Selenium — cofactor for glutathione peroxidase, the enzyme that recycles glutathione; 100–200 µg/day
- Alpha-lipoic acid — helps regenerate oxidised glutathione back to active form
- Sulforaphane (from broccoli sprouts) — activates Nrf2 pathway, upregulating glutathione production
- Exercise — moderate exercise increases glutathione; extreme exercise without recovery depletes it
- Sleep — glutathione is recycled during deep sleep; chronic sleep deprivation depletes stores
Reduce depleters: Alcohol, paracetamol, chronic stress, smoking, and high pollution all burn through glutathione rapidly.
Track your antioxidant defence over time
eterni connects your glutathione levels with NAC intake and other markers — so you can see if your protocol is actually working.
Get early accessFrequently Asked Questions
Can I test my glutathione levels?
Yes, but it's not a standard test. You can request a reduced glutathione (GSH) blood test or a GSH/GSSG ratio. Some labs in India offer it as a specialty test (₹1,500–3,000). The reduced-to-oxidised ratio is more informative than total glutathione alone.
Does oral glutathione work?
Regular glutathione supplements are poorly absorbed because your gut breaks them down. Liposomal glutathione and S-acetyl glutathione are better absorbed. But the most reliable way to raise glutathione is through its precursor NAC (N-acetyl cysteine), which provides the rate-limiting amino acid cysteine.
What depletes glutathione?
Alcohol, paracetamol (acetaminophen), chronic stress, poor sleep, high pollution exposure, smoking, heavy exercise without adequate recovery, and aging all deplete glutathione. People in high-pollution Indian cities may have faster glutathione turnover.
What's better — NAC or glutathione supplements?
NAC is more cost-effective and better studied for raising intracellular glutathione. It costs a fraction of liposomal glutathione and has decades of clinical evidence. For most people, NAC (600–1200 mg/day) is the practical first choice. Liposomal glutathione or IV glutathione may be considered for specific clinical situations.
Why glutathione matters for longevity
Glutathione depletion is one of the nine hallmarks of aging. It plays roles in DNA repair, protein folding, immune regulation, and mitochondrial function. Studies in centenarians consistently show higher glutathione levels compared to age-matched controls.
A landmark 2023 study showed that supplementing older adults with GlyNAC (glycine + NAC) for 16 weeks reversed multiple hallmarks of aging, including oxidative stress, mitochondrial dysfunction, and genomic instability — with glutathione normalisation being the central mechanism.
India-specific considerations
Air pollution in Indian metros (Delhi, Mumbai, Kolkata) creates exceptionally high oxidative stress loads. Studies in Delhi show significantly depleted glutathione levels in residents compared to those in cleaner environments. If you live in a high-pollution city, proactive glutathione support through NAC, selenium, and sleep optimisation becomes even more important.
Connected supplements & biomarkers
- NAC — the most reliable oral precursor to raise glutathione
- Glycine — the other key building block; combine with NAC for GlyNAC protocol
- Selenium — required for glutathione peroxidase enzyme function
- Alpha-lipoic acid — regenerates spent glutathione
- Liver enzymes — the liver is the primary producer and user of glutathione
Know what's working. Know what's not.
eterni connects your lab results, supplements, and retests — so you can see the trajectory, not just a snapshot.
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