Vitamin K1 (Phytonadione)
Plant form of vitamin K for blood clotting. Evidence is mixed, so set expectations accordingly.
Verdict
5/10 Mixed
Evidence
Grade B / 100+ Studies
The No-BS Summary
8 things. 60 seconds. Everything you need.
WHAT IT DOES
Plant form of vitamin K for blood clotting
DOES IT WORK?
5/10 Mixed. K1 is primarily for blood clotting. K2 is better for bones and arteries. K1 is abundant in leafy greens.
HOW MUCH TO TAKE
Follow label
COST
$25-60/month depending on brand and form.
FIRST 24 HOURS
Don't expect miracles on day one. It's building in your system.
AFTER A FEW WEEKS
Most people notice something by week 2-3.
SAFETY
Safe for most people. No red flags at normal doses.
HOW IT FEELS
Supports blood clotting, mostly for deficiency
QUICK ANSWERS
+ 4 more questions
DOSE-RESPONSE CURVE
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