What it is
L-Cysteine is a sulfur-containing amino acid that serves as a direct precursor to glutathione, the body's master antioxidant. It is available in capsule form for oral supplementation.
Supplement · Amino Acid
L-Cysteine
500 mg · vegan · gluten-free · 90 caps
sluggish-detoxificationoxidative stressfatigue liverkidneylungs
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How it works
It directly provides cysteine for the synthesis of glutathione in the liver and other tissues. This process is crucial for neutralizing reactive oxygen species and aiding in the detoxification of xenobiotics and endogenous metabolites.
Who should take it
Adults looking to address sluggish detox, fatigue, skin breakouts. Particularly relevant for people who prefer a targeted single ingredient and who have ruled out an underlying condition that needs medical care first.
Avoid / careful
Pregnant or nursing women without clinician oversight. People on prescription medication affecting the same pathway should consult a doctor before combining. Side effects are uncommon at recommended doses but mild GI upset can occur when starting.
When to take it
Morning
Noon
Evening
Night
How to take it
With food
Empty stomach
Before food
FAQs
Frequently asked
Can L-Cysteine help with skin health?
Yes, by boosting glutathione levels, L-Cysteine can help combat oxidative stress that contributes to skin aging and breakouts, and supports detoxification pathways that can clear impurities.
How long does it take to see results?
For markers related to detoxification and antioxidant status, effects are typically measurable within 4-8 weeks of consistent daily use.
Is L-Cysteine safe for long-term use?
At recommended doses, L-Cysteine is generally considered safe for long-term use. However, consult a clinician for personalized guidance.
Research
6 studies · 2010–2024
Evidence grade
ABCD
C · C · emerging-to-moderate human evidence for liver detoxification and elimination
From the blog
Editorial notes
SacredBod's longer take on L-Cysteine — context the structured blocks above don't capture.
About L-Cysteine
L-Cysteine is a amino acid supplement used to support liver detoxification and elimination. Sulphur amino acid feeding glutathione synthesis. It is available in capsule form and dosed for adults in India and internationally. As a western-tradition entry in the SacredBod catalog, it is positioned as a single-ingredient option that can be used on its own or layered into a broader protocol.
How it works
L-Cysteine works through the mechanisms characteristic of its class — see the mechanism and research sections for detail. It primarily acts on the liver, kidneys, lymphatic system, and effects are dose-dependent, typically becoming measurable within 4-8 weeks for detox markers. Consistency matters more than dose size for this category.
Who it’s for
Adults looking to address sluggish detox, fatigue, skin breakouts. Particularly relevant for people who prefer a targeted single ingredient and who have ruled out an underlying condition that needs medical care first.
Evidence
L-Cysteine carries an evidence grade of C in the SacredBod catalog. Sulphur amino acid feeding glutathione synthesis. See the Research panel above for the underlying studies, participant counts and typical effect sizes.
Dosing & timing
Typical label dose is 500 mg in capsule form. Most adults can expect noticeable effects within 4-8 weeks for detox markers. Consistency matters more than a single large dose — take it daily and re-evaluate against your blood markers at 8–12 weeks.
Cautions
Pregnant or nursing women without clinician oversight. People on prescription medication affecting the same pathway should consult a doctor before combining. Side effects are uncommon at recommended doses but mild GI upset can occur when starting.
As part of the Amino Acid category, L-Cysteine can be used on its own or layered into a broader protocol — see the Goes with panel for synergistic pairings.
Added to your stack.