Overview

SCIENTIFIC SCORE
Possibly Effective
Based on 16 Researches
7.1
USERS' SCORE
Questionable
Based on 24 Reviews
5.9
Supplement Facts
Serving Size: 1 Softgel
Amount Per Serving
%DV
Vitamin K₂ (as MK-7 [Menaquinone-7])
90 mcg

Top Medical Research Studies

We evaluated the effectiveness of vitamin K antagonists (VKAs) in treating left ventricular thrombosis (LVT). Over a year, a cohort of 90 patients was observed for LVT resolution and complications.

By the end of the study, approximately 70% of participants saw their blood clots resolve, with lower success rates linked to factors like reduced heart function. While VKAs showed promise, the treatment's safety profile was also notable, with few severe complications reported.
Read More
8
Thrombosis incidence varies by anticoagulant
We investigated the incidence of bioprosthetic mitral valve thrombosis (bMVT) after transcatheter and surgical mitral valve replacements. Analyzing data from 47 studies involving over 6,000 patients revealed that bMVT occurs more frequently in patients undergoing transcatheter procedures, though not significantly.

Interestingly, those treated with vitamin K antagonists experienced a notably lower incidence of bMVT compared to those on direct oral anticoagulants. This suggests that the choice of anticoagulant could influence thrombotic risks after these heart surgeries.
Read More
7
VKA treatment outcomes in atrial fibrillation
Our study involved a group of 1,350 patients with valvular and nonvalvular atrial fibrillation, all receiving vitamin K antagonists (VKAs). Over about 17 months, we noted an annual incidence of 4.4% for serious events like cardiovascular death and thromboembolic occurrences.

Key predictors included a history of thromboembolism and bleeding, low time in therapeutic range, and reduced kidney function. Notably, while VKAs are crucial, they come with risks that we need to monitor closely to improve patient outcomes.
Read More

Most Useful Reviews

9
Helps blood circulation
22 people found this helpful
As a Coumadin patient, K2 aids in removing calcium deposits from my blood vessels, which is crucial.
Read More
9
Necessary for health
15 people found this helpful
Statin medications impede vitamin K production, so taking MK7 is essential. This formulation in fat-soluble gel capsules enhances absorption, taken from Natto. It's reassuring that it doesn't thicken blood, even with high doses.
Read More
9
Stops nosebleeds
10 people found this helpful
Since taking this product, I’ve had no nosebleeds. It aids blood clotting and is easy to consume.
Read More

Medical Researches

SCIENTIFIC SCORE
Possibly Effective
Based on 16 Researches
7.1
  • All Researches
We examined a narrative review that highlights the effectiveness and safety of the four-factor prothrombin complex concentrate (4F-PCC), particularly Octaplex/Balfaxar. This treatment is designed to enhance clot formation and is available for reversing the effects of vitamin K antagonists like warfarin.

Over 20 years of clinical use revealed that 4F-PCC significantly lowers the international normalized ratio (INR) in patients, helping them achieve better clotting. Interestingly, only a couple of treatment-related thrombotic events were noted, indicating a balanced approach toward clotting without excessive risk.
Read More
We evaluated the effectiveness of vitamin K antagonists (VKAs) in treating left ventricular thrombosis (LVT). Over a year, a cohort of 90 patients was observed for LVT resolution and complications.

By the end of the study, approximately 70% of participants saw their blood clots resolve, with lower success rates linked to factors like reduced heart function. While VKAs showed promise, the treatment's safety profile was also notable, with few severe complications reported.
Read More
8
Apixaban lowers bleeding risk significantly
We aimed to find the best antithrombotic regimen for patients with atrial fibrillation (AF) who recently experienced acute coronary syndrome (ACS) or had a percutaneous coronary intervention (PCI).

In our analysis of a randomized clinical trial, we compared apixaban, a novel anticoagulant, to vitamin K antagonists and evaluated the overall safety and efficiency of these treatments.

Our results showed that apixaban effectively reduced major bleeding events without increasing ischemic risks compared to vitamin K. We recommend using apixaban with a low-potency P2Y inhibitor as the standard care approach.
Read More
8
Thrombosis incidence varies by anticoagulant
We investigated the incidence of bioprosthetic mitral valve thrombosis (bMVT) after transcatheter and surgical mitral valve replacements. Analyzing data from 47 studies involving over 6,000 patients revealed that bMVT occurs more frequently in patients undergoing transcatheter procedures, though not significantly.

Interestingly, those treated with vitamin K antagonists experienced a notably lower incidence of bMVT compared to those on direct oral anticoagulants. This suggests that the choice of anticoagulant could influence thrombotic risks after these heart surgeries.
Read More
8
NOACs outperform VKAs in treatment
We examined how novel oral anticoagulants (NOACs) compare to vitamin K antagonists (VKAs) in treating blood clots in patients with nonvalvular atrial fibrillation.

In our review of 12 studies with nearly 1,000 participants, we found that NOACs achieved better clot-clearing results than VKAs, with a rate of 78% compared to 64%. Importantly, there were no significant differences in safety between these treatments.

Thus, NOACs appear to be a more effective option without increasing adverse events, suggesting a promising alternative for managing blood clots in these patients.
Read More

User Reviews

USERS' SCORE
Questionable
Based on 24 Reviews
5.9
  • All Reviews
  • Positive Reviews
  • Negative Reviews
9
Helps blood circulation
22 people found this helpful
As a Coumadin patient, K2 aids in removing calcium deposits from my blood vessels, which is crucial.
Read More
9
Necessary for health
15 people found this helpful
Statin medications impede vitamin K production, so taking MK7 is essential. This formulation in fat-soluble gel capsules enhances absorption, taken from Natto. It's reassuring that it doesn't thicken blood, even with high doses.
Read More
9
Stops nosebleeds
10 people found this helpful
Since taking this product, I’ve had no nosebleeds. It aids blood clotting and is easy to consume.
Read More
9
Improves gum health
8 people found this helpful
If gums bleed, it's a sign of improper calcium distribution. Vitamin K2 aids calcium movement and prevents accumulation in vessels, strengthening them. It’s crucial if you're low in K2 or taking vitamin D.
Read More
9
Heart health improvement
8 people found this helpful
My husband, after three heart procedures, started this product. At his check-up, his doctor was astonished by his "perfect" ECG. His blood pressure has significantly improved as well.
Read More

Frequently Asked Questions

9
Improved symptoms
1 people found this helpful
It really worked! My vitamin D had been low, causing various symptoms. After learning that K2 helps vitamin D direct calcium properly, I found MK-7 effective. My vitamin D levels improved significantly, and my symptoms faded over two to three weeks. The capsules are small and easy to swallow. I trust Jarrow's non-GMO product and have started giving it to my father to help with his vitamin D deficiency.
9
Helped prevent clots
After experiencing thrombosis, I had issues with easily clogged blood vessels, but I noticed immediate improvements after taking this supplement.
7
Blood thickening caution
1 people found this helpful
Since taking this daily for several months, my ankles are less blue and my legs tire less. I suffered from severe varicose veins, which worsened while on warfarin, prompting me to switch to apixaban. This adjustment allowed necessary vitamin K in my body while avoiding blood clot issues. My hair and nails also grow faster.
9
Heart health improvement
8 people found this helpful
My husband, after three heart procedures, started this product. At his check-up, his doctor was astonished by his "perfect" ECG. His blood pressure has significantly improved as well.
9
Stops nosebleeds
10 people found this helpful
Since taking this product, I’ve had no nosebleeds. It aids blood clotting and is easy to consume.
9
Helps blood circulation
22 people found this helpful
As a Coumadin patient, K2 aids in removing calcium deposits from my blood vessels, which is crucial.
9
Bone health benefit
1 people found this helpful
MK-7 helps osteocalcin, allowing it to bind calcium to form bone matrix effectively. It facilitates the movement of calcium from arteries into bones. Therefore, vitamin K2 is essential for preventing issues like blood clots by regulating calcium levels properly.
7.5
Calcium management
1 people found this helpful
Vitamin K2, combined with vitamin D, aids calcium absorption into bones rather than leaving it in the bloodstream, which can lead to hardening of arteries and blood clots. This is an absorbable form of K2, which I take with my vitamin D and calcium citrate.
0
Not suitable for varicose veins
35 people found this helpful
I was advised not to take vitamin K alongside vitamin D due to my varicose veins, as it could contribute to blood thickening. I agree with my endocrinologist's caution regarding this combination.
2
Supports varicose veins
7 people found this helpful
While on warfarin, I was cautioned against taking blood-coagulating substances, yet this product has helped my tired varicose veins without noticeably affecting my INR.
9
Improves gum health
8 people found this helpful
If gums bleed, it's a sign of improper calcium distribution. Vitamin K2 aids calcium movement and prevents accumulation in vessels, strengthening them. It’s crucial if you're low in K2 or taking vitamin D.
7.5
Convenient consumption
1 people found this helpful
I took it with vitamin D. No side effects were experienced. It ensures calcium does not lead to atherosclerotic plaques, but goes directly to bone tissue. The capsules are odourless and easy to swallow. Long-term use may thicken the blood, so doctor consultation is recommended.
We examined a narrative review that highlights the effectiveness and safety of the four-factor prothrombin complex concentrate (4F-PCC), particularly Octaplex/Balfaxar. This treatment is designed to enhance clot formation and is available for reversing the effects of vitamin K antagonists like warfarin.

Over 20 years of clinical use revealed that 4F-PCC significantly lowers the international normalized ratio (INR) in patients, helping them achieve better clotting. Interestingly, only a couple of treatment-related thrombotic events were noted, indicating a balanced approach toward clotting without excessive risk.
We evaluated the effectiveness of vitamin K antagonists (VKAs) in treating left ventricular thrombosis (LVT). Over a year, a cohort of 90 patients was observed for LVT resolution and complications.

By the end of the study, approximately 70% of participants saw their blood clots resolve, with lower success rates linked to factors like reduced heart function. While VKAs showed promise, the treatment's safety profile was also notable, with few severe complications reported.
7
Vitamin K's role in clot management
We examined the effectiveness of vitamin K antagonists (VKAs) in patients with antiphospholipid syndrome (APS), a condition that increases the risk of blood clots. Our focus was on how monitoring INR levels affects treatment outcomes.

In a case study with two women suffering from APS, we noted that point-of-care testing often showed misleadingly high INR results. This could lead to inappropriate dosing of VKAs and a higher chance of recurrent clots.

However, our findings suggest that by developing individualized correction factors, we could enhance the accuracy of these tests, helping improve VKA management and patient safety.
8
NOACs outperform VKAs in treatment
We examined how novel oral anticoagulants (NOACs) compare to vitamin K antagonists (VKAs) in treating blood clots in patients with nonvalvular atrial fibrillation.

In our review of 12 studies with nearly 1,000 participants, we found that NOACs achieved better clot-clearing results than VKAs, with a rate of 78% compared to 64%. Importantly, there were no significant differences in safety between these treatments.

Thus, NOACs appear to be a more effective option without increasing adverse events, suggesting a promising alternative for managing blood clots in these patients.

References

  1. Karkouti K, Gareis M, Li C, Brandstätter H, Pichotta A, et al. Twenty years of the four-factor prothrombin complex concentrate Octaplex/Balfaxar: A narrative review. Transfus Apher Sci. 2025;64:104115. doi:10.1016/j.transci.2025.104115
  2. Valeriani E, Astorri G, Pannunzio A, Pastori D, Palumbo IM, et al. Long-term left ventricular thrombosis resolution in patients receiving vitamin k antagonists: a multicenter observational study. Intern Emerg Med. 2025. doi:10.1007/s11739-025-03922-6
  3. Geertsema-Hoeve BC, Radin M, Sciascia S, Urbanus RT, Huisman A, et al. Problem Solved? An Individual Ratio between Point-of-Care and Venous International Normalized Ratio Values in Two Patients with Antiphospholipid Syndrome: Two Case Reports. TH Open. 2025;9:a25425358. doi:10.1055/a-2542-5358
  4. Last J, Birschmann I, Lindau S, Konstantinides S, Grottke O, et al. Anticoagulant Management After Emergency Surgery or Major Bleeding in Anticoagulated Patients-Results of the Prospective RADOA Registry. Pharmaceuticals (Basel). 2025;18. doi:10.3390/ph18020170
  5. van de Munckhof A, van Kammen MS, Tatlisumak T, Krzywicka K, Aaron S, et al. Direct oral anticoagulants versus vitamin K antagonists for cerebral venous thrombosis (DOAC-CVT): an international, prospective, observational cohort study. Lancet Neurol. 2025;24:199. doi:10.1016/S1474-4422(24)00519-2
  6. Liporace IL, Oliveira GBF, Alves LBO, Galassi NM, Jeronimo AD, et al. Incidence and Predictors of Clinical Outcomes in Patients with Valvular and Nonvalvular Atrial Fibrillation Using Vitamin K Antagonists. Arq Bras Cardiol. 2025;122:e20240147. doi:10.36660/abc.20240147
  7. Hall EH, Sølsnes MH, Sandberg S, Sølvik UØ. Patient self-management of warfarin therapy - a long-term follow up study. Thromb J. 2025;23:14. doi:10.1186/s12959-025-00694-z
  8. Liu Y, Lam SHM, Romiti GF, Huang B, Chen Y, et al. Renal function and adverse clinical events in anticoagulated patients with atrial fibrillation: insights from the GLORIA-AF Registry Phase III. J Thromb Thrombolysis. 2025;58:165. doi:10.1007/s11239-025-03067-5
  9. Tannu M, Lopes RD, Wojdyla DM, Goodman SG, Aronson R, et al. Antithrombotic Therapy to Minimize Total Events After ACS or PCI in Atrial Fibrillation: Insights From AUGUSTUS. J Am Coll Cardiol. 2025;85:1157. doi:10.1016/j.jacc.2024.10.125
  10. Zorman MJ, Vibhishanan J, Dangas K, Castle J, Li KHC, et al. Valve Thrombosis and Antithrombotic Therapy After Bioprosthetic Mitral Valve Replacement: A Systematic Review And Meta-Analysis. Eur Heart J Cardiovasc Pharmacother. 2025. doi:10.1093/ehjcvp/pvaf005
  11. Mo GL, Wen J, Ye YY, Lu YQ, Gan TM, et al. Efficacy and Safety of New Oral Anticoagulants versus Warfarin in the Resolution of Atrial Fibrillation with Left Atrial/Left Atrial Appendage Thrombus: A Systematic Review and Meta-Analysis. Rev Cardiovasc Med. 2025;26:26055. doi:10.31083/RCM26055
  12. Kempers EK, Visser C, Geijteman ECT, Goedegebuur J, Portielje JEA, et al. Discontinuation of Anticoagulants and Occurrence of Bleeding and Thromboembolic Events in Vitamin K Antagonist Users with a Life-limiting Disease. Thromb Haemost. 2025. doi:10.1055/a-2524-5334
  13. Himmelreich JCL, Virdone S, Camm AJ, Pieper K, Harskamp RE, et al. Emulation of ARISTOTLE and ROCKET AF trials in real-world atrial fibrillation patients results in similar efficacy and safety as original landmark trials: insights from the GARFIELD-AF registry. Open Heart. 2025;12. doi:10.1136/openhrt-2024-002966
  14. Mapelli M, Celeste F, Maiolo G, Mancini E, Agostoni P. Incidental Diagnosis of Massive Mobile Left Ventricle Thrombi Following COVID-19 in a Heart Failure Patient. JACC Case Rep. 2024;29:102870. doi:10.1016/j.jaccas.2024.102870
  15. Gustafsson F, Uriel N, Netuka I, Katz JN, Pagani FD, et al. Aspirin and Hemocompatibility After LVAD Implantation in Patients With Atherosclerotic Vascular Disease: A Secondary Analysis From the ARIES-HM3 Randomized Clinical Trial. JAMA Cardiol. 2025;10:235. doi:10.1001/jamacardio.2024.4849
  16. Premkumar M, Bhujade H, Sharma P, Nain J, Ahluwalia J, et al. Experience With Dabigatran on Rate of Portal Vein Thrombosis Recanalization, Disease Progression and Survival. Aliment Pharmacol Ther. 2025;61:971. doi:10.1111/apt.18474
image