Supplement × Supplement·Evidence index
PubMed indexes 8 records that name Vitamin K1 and Vitamin K2 MK-4 together, either in the title or in an interaction, co-administration, or pharmacokinetic context. Each one is listed below with its study design and, where the abstract states one, the authors’ own conclusion, quoted and linked. This page reports that literature. It does not tell you whether to combine them.
Every statement below is attributed to a named, dated, linked source.
This page lists published research relevant to Vitamin K1 and Vitamin K2 MK-4. It deliberately does not state whether the combination is safe, whether it interacts, in which direction, at what dose, or how far apart to take them.
Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.
“Excess α-tocopherol decreased extrahepatic PK in rats fed PK but not MK-4 in rats fed MK-4.”
Names both Vitamin K1 and Vitamin K2 MK-4 in its title.
“In conclusion, dietary phylloquinone is a source of menaquinone-4 in breast milk. Phylloquinone supplementation to lactating mothers may be of benefit to the newborn infant, since both phylloquinone and menaquinone-4 are raised by supplementation.”
Names both Vitamin K1 and Vitamin K2 MK-4 in its title.
“Samples were measured from 191 healthy volunteers (51.2 ± 16.2 years (mean ± SD)) and the values concerning K1 were 0.044-1.357 ng/mL for women and 0.030-1.214 ng/mL for men. The values for menaquinone-4 and menaquinone-7 did not exhibit any differences between women and men, and were 0.050-1.598 and 0.074-0.759 ng/mL, respectively.”
Names both Vitamin K1 and Vitamin K2 MK-4 in its title.
“However, CAC did not have a significant correlation with plasma levels of PK, MK-4 or MK-7. In conclusion, plasma MK-7, MK-4 or PK level did not show significant correlation with CAC despite the association between plasma vitamin K levels and vitamin K-dependent proteins such as ucOC or PIVKA-2.”
Names both Vitamin K1 and Vitamin K2 MK-4 in its title.
“Vitamin K supplementation seems to tend to prevent bone loss in high-fat diet induced obese state. These findings suggest that vitamin K supplementation reversed the high fat diet induced bone deterioration by modulating osteoblast and osteoclast activities and prevent bone loss in a high-fat diet-induced obese mice.”
Names both Vitamin K1 and Vitamin K2 MK-4 in its title.
“This is the first report concerning IAP mRNA expression induced by oral administration of vitamin K. The results support the possible involvement of vitamin K in the regulation of IAP mRNA expression as a novel pharmacological effect of vitamin K.”
Names both Vitamin K1 and Vitamin K2 MK-4 in its title.
“This data suggests that the ingested phylloquinone was probably converted into MK-4 within the tissues themselves, rather than via hepatic metabolism. The evidence for this is that, after phylloquinone administration, (i) in each of the tissues, the MK-4 concentration increased much more slowly than that of phylloquinone, and (ii) the MK-4 concentration in the plasma and liver reached only much lower levels than those seen in other tissues.”
Names both Vitamin K1 and Vitamin K2 MK-4 in its title.
“Warfarin treatment lowered significantly the MK-4 concentrations, whereas MK-4 epoxide accumulated. The study shows the following: 1) dietary phylloquinone is accumulated mainly in the heart and liver, 2) the MK-4 accumulation in nonhepatic organs is due to synthesis rather than uptake and 3) MK-4 rather than phylloquinone may be the functional vitamin in nonhepatic organs.”
Names both Vitamin K1 and Vitamin K2 MK-4 in its title.
Search-based evidence indexes have real limits, and it is worth being explicit about them:
NutriStack is a free iPhone app for organising a supplement routine: what you take, when, and what the published record says about it. Its exploratory interaction checker covers Vitamin K1, Vitamin K2 MK-4, and several hundred other substances.
The checker is a research and organisation tool, not a clinical decision aid, and its per-pair assessments are excluded from search until they pass claim-level review.
NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.
