Phylloquinone intake in people on haemodialysis compared with healthy controls
What it found
People on haemodialysis took in roughly half the phylloquinone (vitamin K1) of healthy adults.
Between 70% and 90% fell below recommended levels, about double the rate seen in controls.
What they found
Studies in people
Lower phylloquinone in dialysis patients
Dialysis patients took in significantly less phylloquinone than healthy controls. This gap remained even when researchers adjusted for body weight or total calories eaten.
Most patients fell short
Depending on the guideline used, 71% to 89.2% of dialysis patients did not meet recommended phylloquinone intakes. That was roughly double the shortfall seen in the healthy group. Using a measure based on body weight, 49.5% of patients were low compared with 24.7% of controls.
Overall eating was reduced
Dialysis patients ate less overall, taking in fewer calories, proteins, fats, carbohydrates, fibre and minerals. Most vitamins, including A, C, D and E, were also lower, except for vitamin B12 which was similar in both groups.
Linked nutrients identified
A statistical model pointed to low vitamin A and low iron intake as markers that predicted a phylloquinone shortfall. The authors note the iron link is new and needs more study.
Other findings
Food sources of phylloquinone
Phylloquinone comes mainly from green leafy vegetables and cabbages, which supply 40% to 50% of typical intake. Because it dissolves in fat, eating it with vegetable oils like olive oil helps the gut absorb it.
What the authors conclude
- They conclude that people on haemodialysis take in far too little phylloquinone, which could raise their risk of broken bones and hardened blood vessels.
- They advise that dietary guidance for dialysis patients should pay attention to getting enough vitamin K from food.
- The authors say it still needs to be proven whether eating more phylloquinone or taking supplements actually improves health outcomes in these patients.
How it was done
Vitamin K helps activate proteins that build bone and keep blood vessels from hardening. People on dialysis often cut back on green vegetables to control potassium, which may also lower their vitamin K1 intake, but little data existed for those eating a Mediterranean diet.
Researchers tracked what 91 adults on dialysis and 85 healthy adults ate over seven consecutive days. Participants kept detailed food journals between 2013 and 2014, which staff then checked in person.
What it can’t tell you
- This work only recorded what people ate, so it cannot show whether low phylloquinone directly causes bone fractures or hardened arteries.
- Food journals rely on memory and honesty, meaning actual intakes could be higher or lower than reported.
- The study did not measure vitamin K levels in the blood, so scientists do not yet know how much of the missing intake translated into a true deficiency.
Who paid
- Authors work at
- National Research Council (CNR) - Institute of Clinical Physiology (IFC), Italy; University of Padua, Italy; University of Pisa, Italy
The paper
- Title
- Low vitamin K1 intake in haemodialysis patients
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Fusaro M, D'Alessandro C, Noale M, et al (2017). Low vitamin K1 intake in haemodialysis patients. Clinical nutrition (Edinburgh, Scotland). doi:10.1016/j.clnu.2016.04.024Free full textPubMed 27234935DOI
Summary written 1 Oct 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error