Vitamin K is an essential nutrient that plays a crucial role in blood clotting, bone health, and heart health. While it is often overshadowed by other vitamins, its importance cannot be overstated. This article will explain the different forms of vitamin K, how the VKORC1 gene helps recycle it, and how genetic variations (SNPs) can influence its metabolism and increase the risk of deficiency. Additionally, we will explore the relationship between vitamin K, vitamin D, and bone health, as well as the benefits of weight-bearing exercise.
Forms and Functions of Vitamin K
Vitamin K exists in two main forms:
- Vitamin K1 (Phylloquinone) – Found in green leafy vegetables like spinach, kale, and broccoli. It plays a key role in blood clotting.
- Vitamin K2 (Menaquinones) – Found in fermented foods, animal products, and made by gut bacteria. It is more involved in bone health and cardiovascular function.
Why Do We Need Vitamin K?
Vitamin K is essential for activating proteins that regulate:
- Blood clotting – Preventing excessive bleeding from injuries.
- Bone metabolism – Supporting bone strength by activating osteocalcin, a protein that binds calcium to bones.
- Heart health – Helping prevent calcium buildup in arteries, reducing the risk of cardiovascular diseases.
How VKORC1 Recycles Vitamin K
Vitamin K is used in the body through a cycle known as the Vitamin K Cycle. Once vitamin K has been used to activate clotting factors or bone-related proteins, it is converted into an inactive form called vitamin K epoxide.
The VKORC1 gene (Vitamin K Epoxide Reductase Complex 1) produces an enzyme that recycles inactive vitamin K epoxide back into its active form so the body can reuse it. This process ensures a continuous supply of vitamin K for proper blood clotting and bone health.
Below you can see an example of an illustrated Vitamin K Cycle.
VKORC1 and Genetic Variation: The rs9923231 SNP
One common genetic variation (SNP) in the VKORC1 gene is rs9923231. This variation can reduce the efficiency of vitamin K recycling, leading to lower active vitamin K levels in the body. As a result:
- People with this SNP may be more prone to vitamin K deficiency, leading to easy bruising, excessive bleeding, and weaker bones.
- It also makes individuals more sensitive to warfarin, a blood-thinning medication that works by inhibiting VKORC1. People with this genetic variant may require lower doses of warfarin to avoid excessive bleeding.
How Can VKORC1 SNPs Affect You?
If you have a genetic variant in VKORC1 that reduces vitamin K recycling, you may experience:
- Increased risk of bone fractures due to reduced osteocalcin activation.
- Higher likelihood of bruising and bleeding because of slower blood clotting.
- Greater sensitivity to warfarin, requiring close medical supervision if prescribed this drug.
What Can You Do About It?
If you have a VKORC1 SNP that affects vitamin K metabolism, you can take the following steps to reduce the risk of deficiency:
- Increase Vitamin K Intake: Eat more vitamin K-rich foods like leafy greens, fermented foods (natto, kimchi), and grass-fed dairy.
- Consider Vitamin K2 Supplements: Since K2 stays in the body longer than K1, it may help maintain adequate vitamin K levels.
- Regular Blood Clotting Checks: If you take blood thinners like warfarin, your doctor may monitor your clotting time (INR) more closely.
- Bone Health Support: Pair vitamin K with vitamin D and weight-bearing exercise to strengthen bones.
Vitamin K, Vitamin D, and Bone Health
Vitamin K and vitamin D work together to keep bones strong:
- Vitamin D helps the body absorb calcium from food.
- Vitamin K directs calcium into bones and prevents it from accumulating in arteries.
Without enough vitamin K, calcium may deposit in blood vessels instead of bones, increasing the risk of osteoporosis and heart disease.
The Role of Weight-Bearing Exercise
Weight-bearing exercises like walking, running, and strength training help maintain bone density by stimulating bone-forming cells. When combined with adequate vitamin K and D levels, these exercises can:
- Improve bone strength and reduce fracture risk.
- Enhance calcium absorption and retention.
- Support overall mobility and longevity.
Conclusion
Vitamin K is crucial for blood clotting, bone health, and heart function. The VKORC1 gene plays a key role in recycling vitamin K, and genetic variations like rs9923231 can reduce this recycling process, leading to potential health risks. By eating vitamin K-rich foods, supplementing if necessary, and engaging in weight-bearing exercise, individuals can support their bone health and overall well-being. Understanding your genetic profile can also help tailor your approach to vitamin K intake and medical treatments for optimal health.