L-Cystine
Two cysteines bonded. Hair and nail builder. Evidence is mixed, so set expectations accordingly.
Verdict
4/10 Limited
Evidence
Grade B / 100+ Studies
The No-BS Summary
8 things. 60 seconds. Everything you need.
WHAT IT DOES
Two cysteines bonded. Hair and nail builder.
DOES IT WORK?
4/10 Limited. Oxidized form of cysteine. Important for hair, nails, and keratin. NAC is often preferred for antioxidant benefits.
HOW MUCH TO TAKE
500-1500mg daily
COST
Budget-friendly. $20-35/month for quality brands.
FIRST 24 HOURS
Don't expect miracles on day one. It's building in your system.
AFTER A FEW WEEKS
Give it 4-8 weeks for full effects. Patience pays.
SAFETY
One heads-up: kidney_caution. Otherwise, you're good.
HOW IT FEELS
No immediate effects. Cosmetic benefits over time.
QUICK ANSWERS
+ 4 more questions
DOSE-RESPONSE CURVE
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