Vitamin K is a fat soluble vitamin that plays a critical role in blood clotting and in bone health. Vitamin K2 (menaquinone) is a natural form of vitamin K that is synthesized by our normal flora (intestinal bacteria). The flora produce about 30% of our total daily need of vitamin K. Vitamin K1 (pylloquinone) is synthesized by green plants, therefore, dark green leafy vegetables are a rich source of vitamin K. Vitamin K3 (Menadione) is a synthetic version of the vitamin. It is commonly injected into new born infants. This is not a practice I recommend.
Signs & Symptoms of Vitamin K Deficiency:
- Easy bruising
- Spontaneous nosebleeds
- Blood in the urine
- Gastrointestinal bleeding
- Bone loss (osteopenia)
Vitamin K has been shown to be beneficial in the following conditions:
- Cancer
- Osteoporosis
- Bleeding disorders
- Epistaxis
Drugs/Medications that deplete or interfere with Vitamin K:
- Broad-spectrum antibiotics: deplete normal flora thus decreasing vitamin K synthesis
- Coumarin – anticoagulant drugs (warfarin) inhibit vitamin K cycle
- Bile acid sequestrants – may inhibit absorption of vitamin K
- Mineral oil – may inhibit absorption of vitamin K
- Olestra – (food additive) may inhibit absorption of vitamin K
- Broad-spectrum antibiotics: deplete normal flora thus decreasing vitamin K synthesis
- Coumarin – anticoagulant drugs (warfarin) inhibit vitamin K cycle
- Bile acid sequestrants (cholesterol lowering medications) – may inhibit absorption of vitamin K
- Mineral oil – may inhibit absorption of vitamin K
- Olestra – (fat substitute food additive) may inhibit absorption of vitamin K
Laboratory testing to detect Vitamin K deficiency:
- Lymphocyte functional testing
- Prothrombin time
- Osteocalcin
Food Sources:
- Spinach, collard greens, and other dark green leafy vegetables