Vitamin K status, supplements and kidney function in CKD
What it found
In people with chronic kidney disease, vitamin K supplements improved vitamin K status markers but did not consistently improve kidney function.
In population studies, low vitamin K status was linked to worse kidney function, though many links weakened after accounting for baseline kidney function.
What they found
Studies in people
Supplementation and kidney markers
Across nine trials, vitamin K supplements improved markers of vitamin K status but showed no consistent benefit on kidney function measures such as eGFR, creatinine or proteinuria. Two studies found a significant decline in kidney function after supplementation.
Low vitamin K status and kidney function
Seven cohort studies found links between low vitamin K status (high dp-ucMGP levels) and worse kidney function, including reduced eGFR, incident CKD, microalbuminuria, and end-stage kidney disease. Many of these links weakened or disappeared after adjusting for baseline kidney function.
Kidney transplant recipients
In kidney transplant recipients, one cohort study found that high dp-ucMGP levels were linked to higher risk of graft failure even after full adjustment, while another found the link weakened after adjusting for baseline eGFR. Trials in transplant recipients showed no treatment effect on eGFR or proteinuria.
Type 1 diabetes and CKD cohorts
In a type 1 diabetes cohort, higher dp-ucMGP levels were linked to a higher risk of end-stage kidney disease, but this link was lost after adjusting for baseline eGFR, albuminuria and diabetes duration. In a small CKD cohort, higher dp-ucMGP levels were linked to a 4.02 times higher risk of a 30% or greater drop in eGFR or progression to end-stage kidney disease.
Animal and lab studies
Animal study on vitamin K
An experimental study in rats found that vitamin K1 supplementation had beneficial effects on insulin, blood glucose, creatinine, albumin-creatinine ratio, urea and uric acid after damage to pancreatic beta cells. The authors note this could point to a protective role of vitamin K against diabetes-related kidney effects.
What the authors conclude
“No clear effect of supplementation was observed on the reported kidney markers in patient populations.”
Also in their conclusions
- They conclude that observational studies show a link between low vitamin K status and worse kidney function over time.
- They state that interventional studies did not suggest that vitamin K supplementation could prevent decline in kidney function markers.
- They call for more cohort studies and clinical trials in larger patient groups with kidney endpoints to clarify whether vitamin K supplementation could prevent kidney function decline or CKD development in high-risk groups.
How it was done
The authors wanted to review the evidence on whether vitamin K deficiency or supplementation affects kidney function, because vitamin K deficiency is common in CKD patients but the therapeutic effects of supplementation are uncertain.
They searched PubMed for studies on vitamin K status or supplementation and kidney outcomes. They included 16 studies: 9 clinical trials (8 randomised, 1 non-controlled) and 7 cohort studies, in general adult populations and in patients with CKD, kidney transplants, haemodialysis, or type 1 diabetes.
What it can’t tell you
- The cohort studies can show links over time but cannot prove that low vitamin K status causes kidney function decline.
- The trials tested specific doses and forms of vitamin K for limited durations, so they cannot show whether other doses or longer use might work.
- The animal study results cannot be directly applied to people.
Who paid
- Conflicts
- A. Linneberg has received investigational products from Kappa Bioscience AS for an intervention trial (The InterVitaminK Trial; clinicatrials.gov identifier NCT05259046) using vitamin K2 supplements as the active intervention. The remaining authors declare no personal or financial conflicts of interest.
- Authors work at
- University of Copenhagen, Denmark; Copenhagen University Hospital, Denmark
The paper
- Title
- The Role of Vitamin K Deficiency in Chronic Kidney Disease-A Scoping Review
- Type
- Study
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Tybjerg Wegge V, Kjær Torbensen M, Linneberg A, Aaberg Lauridsen J (2025). The Role of Vitamin K Deficiency in Chronic Kidney Disease-A Scoping Review. Nutrients. doi:10.3390/nu17152559Free full textPubMed 40806143DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error