vitamin

Vitamin K

Supports blood clotting and bone metabolism.

What It Does

Vitamin K activates proteins involved in coagulation.

It also participates in bone-related protein carboxylation.

Who Needs It Most

DemographicTarget IntakeUpper Limit
all, age:31-120, postmenopause, osteoporosis, perimenopause90-120 mcg (K total); 100-200 mcg K2No established UL
all, age:0-1Single 1mg injection at birthNo established UL

Signs of Deficiency

  • Easy bruising
  • Bleeding tendency

Best Food Sources

Leafy greens

High

Broccoli

Moderate

Soybean oil

Moderate

Supplement Guide

Best forms: Phylloquinone (K1), Menaquinones (K2)

What to look for: Medication interaction warning on label

What to avoid: Self-adjusting intake if on warfarin

Timing: With meals containing fat.

Who Should Avoid It

No major common contraindications in our database for this nutrient. Always check medication interactions.

The Research

PubMed citations are temporarily unavailable.

NIH Fact Sheet

Want personalized dosing?

Take the VitaGuide quiz to build your stack based on your profile.

Take the Quiz