Summary
Vitamin K2 plays a critical role in calcium regulation — preventing calcium buildup in soft tissues like coronary arteries and joints, while directing it into the bones for structural strength. This is distinct from Vitamin K1, which primarily supports blood clotting. Dr. Berg outlines the top food sources of K2 and recommended dosage protocols, including pairing K2 with Vitamin D3.
Key Takeaways
- K2 ≠ K1: K1 is primarily for stopping bleeding; K2 manages calcium distribution in the body
- K2’s main function: Prevents calcium from accumulating in soft tissues (coronary arteries, joints) and directs it into bones
- Maintenance dose: 100 micrograms of K2 per day
- Therapeutic dose: Up to 400 micrograms per day
- Always pair K2 with D3: Follow the 1:100 ratio (100 mcg K2 per 10,000 IU of D3)
- Natto is the highest food source of K2, followed by organ meats and aged cheeses
- Food quality matters: Opt for pasture-raised, organic, and grass-fed sources to maximize K2 content
Details
K2 vs. K1
These are two distinct vitamins with separate functions:
- K1 — involved in blood coagulation; deficiency may cause bruising
- K2 — regulates calcium metabolism, protecting cardiovascular health and supporting bone density
Dosage Protocol
| Goal | K2 Dose | D3 Dose |
|---|---|---|
| Maintenance | 100 mcg | 10,000 IU |
| Therapeutic | 200 mcg | 20,000 IU |
| Maximum therapeutic | 400 mcg | 40,000 IU |
Dr. Berg emphasizes pairing K2 with D3 because both work synergistically in calcium metabolism.
Top Food Sources of Vitamin K2 (Highest to Lower)
- Natto — fermented soybean product; the single richest source of K2
- Organ meats — goose liver, duck liver, chicken liver, beef liver (recommended as pâté)
- Egg yolks — pasture-raised, organic eggs preferred
- Grass-fed beef
- Emu oil
- Hard and soft cheeses — Gouda cheese specifically highlighted
- Fermented/cured meats — pepperoni, salami, pork sausage
- Grass-fed dairy — butter, sour cream, cream cheese
- Sauerkraut — contains smaller amounts of K2
Quality Considerations
For eggs, beef, and dairy, pasture-raised, organic, and grass-fed options contain meaningfully higher K2 levels compared to conventionally raised products.