Know what you're putting in your body.

158 herbs, nutrients, and compounds. What the science says, what tradition knew, and what to watch for. Founding members keep this running.

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Vitamin K

also known as Vitamin K1, Phylloquinone, Phytonadione, Vitamin K2…

Supports blood clotting, bone formation and repair, calcium use, osteoporosis prevention, vascular health, liver function, glucose storage, infection resistance, and longevity.

Recommended daily intake

Adult Men · 120 mcg (adequate intake)
Adult Women · 90 mcg (adequate intake)
K2 Separate Intake · no formal RDA for K2 specifically; clinical research uses 90-180 mcg of MK-7

Upper intake limit

Not formally established

Signs of deficiency

Easy bruising and bleeding
Heavy menstrual bleeding
Blood in urine or stool
Soft, fragile bones
Calcification in arteries (suggested by some research as a sign of K2 inadequacy)

Supports prothrombin production
Supports normal blood clotting
Supports bone formation
Supports bone repair
Supports calcium use in bones
May help prevent osteoporosis
May protect vascular health by reducing artery calcification
Supports liver function

Works with

Vitamin D Vitamin K2 activates osteocalcin and matrix Gla protein, directing calcium absorbed via vitamin D into bone rather than soft tissue. Calcium Vitamin K2 carboxylates osteocalcin, enabling it to bind calcium in bone matrix; the two are synergistic for bone mineral density.

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