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Last reviewed: May 12, 2026 Last updated: May 12, 2026

Written by: Jay Hastings , CEO of PlexusDx

Jay Hastings is the CEO of PlexusDx, a precision health company focused on genetic testing, blood biomarker insights, and personalized wellness recommendations. He has more than 20 years of experience across healthcare innovation, genomics, laboratory operations, healthcare investing, and strategic finance. His work has included scaling healthcare startups, leading CLIA lab integrations, and helping expand consumer access to precision health tools.

Medically reviewed by: Jayden Lee, PharmD, EMBA

Jayden Lee, PharmD, EMBA, is the PlexusDx Medical Science Liaison with a PharmD and MBA specializing in pharmacogenomics and clinical product development, with a proven ability to bridge the gap between genomic research and practical patient outcomes. Dr. Lee has more than 10 years of professional experience in clinical pharmacy, academia, and research.

How CYP4F2 and Vitamin K1 Influence Your Health

Vitamin K is a fat soluble nutrient important for blood clotting, bone strength, and healthy arteries. It prevents calcium buildup in blood vessel walls and supports proteins involved in bone formation. Vitamin K1 is found mainly in green leafy vegetables and plant oils. Vitamin K2 is found in animal products and fermented foods and plays a complementary role in directing calcium to bone rather than soft tissue.

The CYP4F2 gene makes an enzyme that helps regulate Vitamin K1 by breaking it down. Differences in this gene change how quickly Vitamin K1 is cleared from your body and can influence your circulating Vitamin K1 levels. Knowing your CYP4F2 genotype can help you understand how your diet and lifestyle might interact with your body’s handling of Vitamin K1.

Quick overview

  • Vitamin K1: mostly in leafy greens, important for clotting and vascular health.
  • Vitamin K2: in fermented foods and animal products, important for bone and vascular health.
  • CYP4F2: enzyme that breaks down Vitamin K1; certain gene variants reduce enzyme function and slow Vitamin K1 clearance.

Practical guidance

  • Eat a variety of Vitamin K sources: include leafy greens, cruciferous vegetables, fermented foods, and moderate amounts of animal products if appropriate for your diet.
  • Consume Vitamin K foods with healthy fats such as olive oil, avocado, nuts, or seeds to improve absorption.
  • Be consistent with Vitamin K intake if you take blood thinning medications. Any changes to diet or supplements should be discussed with your healthcare provider.
  • Consider blood tests when appropriate: vitamin K status can be indirectly assessed through markers of clotting function and, in some cases, direct measurements ordered by a clinician.

Genetic interpretation: CYP4F2 rs2108622

Below are straightforward interpretations for each genotype at the rs2108622 location in CYP4F2. Use the accordion to view the section that matches your genotype. These summaries explain how the genotype affects enzyme function and what that might mean for dietary and lifestyle choices.

2 effect alleles — TT (reduced enzyme function)

If your genotype is TT, you carry two copies of the effect allele. This is associated with reduced CYP4F2 enzyme activity, which means your body may break down Vitamin K1 more slowly. As a result, dietary Vitamin K1 from foods like spinach, kale, broccoli, and other green leafy vegetables may stay in circulation longer and lead to higher average Vitamin K1 levels compared to people with other genotypes.

Considerations and practical tips:

  • Diet: You can include leafy greens regularly, but be mindful of large or abrupt increases in Vitamin K intake if you are on medications that affect clotting. Maintain a consistent pattern of Vitamin K intake to help your clinician interpret any blood tests.
  • Supplements: Avoid starting high dose Vitamin K supplements without medical supervision, especially if you use blood thinners. A standard multivitamin with typical amounts of Vitamin K is usually safe, but check with your clinician.
  • Lifestyle: Pair Vitamin K rich foods with healthy fats for best absorption. Regular physical activity and a balanced diet support bone and vascular health.
  • Testing: If you take anticoagulant medication or have concerns about clotting or bone health, discuss targeted blood tests with your healthcare provider.
1 effect allele — CT (likely reduced enzyme function)

If your genotype is CT, you carry one copy of the effect allele and are likely to have mildly reduced CYP4F2 function. Your body may clear Vitamin K1 somewhat more slowly than someone without the effect allele. Dietary Vitamin K1 from leafy greens and other sources may remain higher for longer periods, potentially increasing circulating levels depending on how much Vitamin K you eat.

Considerations and practical tips:

  • Diet: Maintain a varied intake of Vitamin K foods. Consistency is important if you are taking medications that are sensitive to Vitamin K.
  • Supplements: Use caution with high dose Vitamin K supplements. Discuss any supplements with your healthcare provider, especially if you take anticoagulants.
  • Lifestyle: Enjoy a balanced diet with healthy fats to aid Vitamin K absorption. Weight bearing exercise and adequate calcium and vitamin D support bone health along with Vitamin K.
  • Testing: If clinically indicated, your provider may monitor clotting markers more frequently during diet or medication changes.
0 effect alleles — CC (typical enzyme function)

If your genotype is CC, you carry two copies of the non-effect allele and your CYP4F2 enzyme typically functions at standard efficiency. Your body processes Vitamin K1 at a routine rate, and your Vitamin K1 levels are likely to reflect your dietary intake without the slower clearance seen in the other genotypes.

Considerations and practical tips:

  • Diet: Continue eating a variety of Vitamin K rich foods such as leafy greens for Vitamin K1 and fermented foods or certain animal products for Vitamin K2.
  • Supplements: Routine multivitamins that contain Vitamin K are usually sufficient for most people. Only consider additional supplementation under clinical guidance.
  • Lifestyle: Absorb Vitamin K better by eating it with healthy fats. Maintain regular exercise and bone supporting nutrients like calcium and vitamin D.
  • Testing: Usual care and screening practices apply. Discuss any concerns about clotting, bone health, or cardiovascular risk with your healthcare provider.

Diet, supplements, and lifestyle — practical recommendations

Food-based approaches are the safest way to support Vitamin K status for most people.

Dietary tips

  • Include leafy greens daily in meals: spinach, kale, collard greens, Swiss chard, and lettuce varieties.
  • Add cruciferous vegetables: broccoli and Brussels sprouts contribute Vitamin K and other nutrients.
  • Include fermented foods and select animal products for Vitamin K2: natto, certain cheeses, and grass fed meats if they fit your diet.
  • Always eat Vitamin K rich foods with a source of healthy fat such as olive oil, avocado, nuts, seeds, or full fat dairy to improve absorption.

Supplement guidance

  • A standard multivitamin that contains the recommended daily amount of Vitamin K is typically sufficient for most people.
  • Do not start high dose Vitamin K supplements without consulting your clinician, especially if you take blood thinning medication.
  • If you have concerns about bone health or vitamin levels, ask your healthcare provider about targeted testing and tailored supplement advice.

Lifestyle and monitoring

  • Stay active with weight bearing exercise to support bone strength.
  • Maintain consistent dietary patterns of Vitamin K to minimize fluctuations that could matter if you are on medications affecting clotting.
  • Discuss lab testing with your clinician if you take anticoagulants, have a bleeding or clotting disorder, or have concerns about bone or vascular health.

Important notice

PlexusDx provides educational information about genetic predispositions only. This content is not medical advice. Always consult your healthcare provider before making changes to medications, diet, or supplements based on genetic information. Your clinician can interpret this information in the context of your full medical history, current medications, and clinical testing. If you are on blood thinning medications, do not change your diet or supplements without medical supervision.

If this genetic variant is present in your PlexusDx results, the following tests and reports are commonly used to explore it further:

🧬 Genetic Tests:

🧪 Blood Tests:

📄 Genetic Report:

Frequently Asked Questions About Vitamin K and CYP4F2 rs2108622

What does the CYP4F2 rs2108622 genotype mean for vitamin K1 levels?

CYP4F2 rs2108622 affects how quickly your body breaks down Vitamin K1. If you carry the effect allele (CT or TT), CYP4F2 activity is reduced, which can slow Vitamin K1 clearance and may lead to higher circulating Vitamin K1 levels compared with the typical CC genotype.

How should I adjust my diet for vitamin K1 and vitamin K2 based on CYP4F2 rs2108622?

For most people, support Vitamin K status with food-based consistency: eat leafy greens daily for Vitamin K1 (spinach, kale, broccoli, collards) and include fermented foods and select animal products for Vitamin K2 (natto, certain cheeses, grass-fed meats if appropriate). Pair Vitamin K foods with healthy fats (olive oil, avocado, nuts, seeds) to improve absorption, and aim for a stable intake pattern—especially if you’re medication-sensitive to Vitamin K.

Is vitamin K supplementation safe if I have CYP4F2 rs2108622 and take blood thinners?

Be cautious with high-dose Vitamin K supplements. If you take blood thinning medications, do not change diet or supplements without medical supervision, regardless of genotype. In most cases, a standard multivitamin with typical Vitamin K amounts may be sufficient, but targeted discussion with your healthcare provider is recommended, and blood tests may be used when clinically appropriate.

What tests can help me learn more about Vitamin K and CYP4F2 rs2108622?

The Optimal Diet and Weight Loss Genetic Test delivers over 295 genetic insights related to nutrition response, body composition, metabolism, and fitness. The Diet and Nutrition Genetic Report translates your results into personalized, actionable guidance. Your healthcare provider can also recommend targeted blood tests based on your specific pathway results and health history to complement your genetic insights with current biomarker data.

Medical and Editorial Standards

Medical review process: This article was reviewed for medical accuracy, scientific clarity, evidence alignment, and appropriate discussion of genetics, medications, supplements, biomarkers, and health-related claims.

Sources and evidence: PlexusDx educational content is developed using peer-reviewed research, clinical literature, reputable medical references, and, where applicable, public health or regulatory guidance. References are included at the end of the article when scientific, medical, or health-related claims are discussed.

Commercial transparency: PlexusDx offers genetic testing, blood biomarker testing, personalized supplement recommendations, and related precision wellness services. Product mentions are intended to help readers understand available options and should not be interpreted as medical advice.

Important disclaimer: PlexusDx educational content is for informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making decisions about medications, supplements, genetic testing, lab testing, or health-related care.