Vitamins K1 and K2: The Emerging Group of Vitamins Required for Human Health.

2017
Journal of nutrition and metabolism 2017
- Gerry Kurt Schwalfenberg

PubMed: 28698808
DOI: 10.1155/2017/6254836

Study Design

Type: Review
Methods: PubMed search for articles on vitamin K (K1 and K2) along with books and conference proceedings

Objective

To review the evidence for the use of vitamin K supplementation in clinical conditions such as osteoporosis, vascular calcification, arthritis, cancer, renal calculi, diabetes, and warfarin therapy.

Quality of evidence

PubMed was searched for articles on vitamin K (K1 and K2) along with books and conference proceedings and health conditions listed above. Level I and II evidence supports the use of vitamins K1 and K2 in osteoporosis and Level II evidence supports vitamin K2 in prevention of coronary calcification and cardiovascular disease. Evidence is insufficient for use in diabetes, arthritis, renal calculi, and cancer.

Main message

Vitamin K2 may be a useful adjunct for the treatment of osteoporosis, along with vitamin D and calcium, rivaling bisphosphonate therapy without toxicity. It may also significantly reduce morbidity and mortality in cardiovascular health by reducing vascular calcification. Vitamin K2 appears promising in the areas of diabetes, cancer, and osteoarthritis. Vitamin K use in warfarin therapy is safe and may improve INR control, although a dosage adjustment is required.

Conclusion

Vitamin K supplementation may be useful for a number of chronic conditions that are afflicting North Americans as the population ages. Supplementation may be required for bone and cardiovascular health.

Research Insights

Vitamin K→Improved INR Control
Vitamin K use in warfarin therapy is safe and may improve INR control, although a dosage adjustment is required.
Effect
Beneficial
Effect size
Moderate
Vitamin K→Reduced Arthritis Symptoms
Evidence is insufficient for use in diabetes, arthritis, renal calculi, and cancer.
Effect
Neutral
Effect size
Small
Vitamin K→Reduced Cancer Incidence
Evidence is insufficient for use in diabetes, arthritis, renal calculi, and cancer.
Effect
Neutral
Effect size
Small
Vitamin K→Reduced Diabetes Incidence
Evidence is insufficient for use in diabetes, arthritis, renal calculi, and cancer.
Effect
Neutral
Effect size
Small
Vitamin K→Reduced Renal Calculi
Evidence is insufficient for use in diabetes, arthritis, renal calculi, and cancer.
Effect
Neutral
Effect size
Small
Vitamin K1→Improved Osteoporosis Treatment
Level I and II evidence supports the use of vitamins K1 and K2 in osteoporosis
Effect
Beneficial
Effect size
Moderate
Vitamin K2→Improved Osteoporosis Treatment
Level I and II evidence supports the use of vitamins K1 and K2 in osteoporosis
Effect
Beneficial
Effect size
Moderate
Vitamin K2→Reduced Cardiovascular Disease Risk
Level II evidence supports vitamin K2 in prevention of coronary calcification and cardiovascular disease.
Effect
Beneficial
Effect size
Moderate
Vitamin K2→Reduced Coronary Artery Calcification
Level II evidence supports vitamin K2 in prevention of coronary calcification and cardiovascular disease.
Effect
Beneficial
Effect size
Moderate

Adverse Events Reported

Vitamin K→Overall tolerability
Vitamin K use in warfarin therapy is safe and may improve INR control, although a dosage adjustment is required.
Finding
Reported
Vitamin K2→Overall tolerability
Vitamin K2 may be a useful adjunct for the treatment of osteoporosis, along with vitamin D and calcium, rivaling bisphosphonate therapy without toxicity.
Finding
Reported