Question explored with the scientific record
Conversation so far
- 1 Side effects of proton pump inhibitors
- 2 Side effects of reducing stomach acid
- 3 Any risk Taking calcium tablets
- 4 Does vitamin K reduce risks from Taking calcium tablets
- 5 Does vitamin K reduce risks from Taking vitamin D
Answered on this page ↓
Does vitamin K reduce risks from Taking vitamin D
The short version: vitamin K is a plausible partner to vitamin D for the calcium-handling side, but no human trial here shows it prevents the harms of vitamin D, and the vitamin D risks themselves are mostly dose-dependent.
The mechanism is real. Vitamin D raises matrix Gla protein, the vitamin K-dependent protein that keeps calcium out of arteries, two to three fold [1]. Prolonged vitamin D at just 400 IU a day was linked to more hypercalciuria, kidney stones, hypercalcemia, and vascular lesions [1]. That is the case for pairing them.
The direct test is thin. In a 3-year trial, vitamin K1 plus calcium and vitamin D versus calcium and vitamin D alone showed no difference in coronary calcium overall, though adherent participants and those with existing calcium had less progression [3]. That is a subgroup signal, not a proven benefit.
| Finding | What it shows |
|---|---|
| Vitamin D raises MGP 2-3x [1] | Mechanism for K pairing |
| D at 400 IU/day linked to stones, high calcium [1] | Risk is dose-related |
| K1 vs K1+calcium+D, coronary calcium [3] | No overall difference; subgroup only |
| K status and mortality in heart disease [2] | Association, not causation |
My call: vitamin K is low-risk and mechanistically sensible alongside vitamin D, but the human outcome evidence is a subgroup signal, not proof. Confidence: low.
Sources used 3
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Matrix-GLA-Protein and Vascular Calcification: Can Diet Influence the Consequences of Matrix GLA Protein Inactivation? A Review
Dietary factors, particularly vitamin K and vitamin D interactions, modulate Matrix GLA Protein (MGP) carboxylation and related calcification pathways, with evidence from the reviewed literature suggesting diet can influence vascular calcification risk in CKD and other settings.
DOI: 10.23958/ijirms/vol06-i10/1235 -
The coincidence of low vitamin K status and high expression of growth differentiation factor 15 may indicate increased mortality risk in stable coronary heart disease patients
This prospective study in stable coronary heart disease patients shows that concurrent high desphospho-uncarboxylated matrix Gla protein (dp-ucMGP; low vitamin K status) and high growth differentiation factor-15 (GDF-15) at baseline identify a markedly increased risk of all-caus…
DOI: 10.1016/j.numecd.2020.09.015 -
Vitamin K supplementation and progression of coronary artery calcium in older men and women
A 3-year, double-blind randomized trial tested whether daily vitamin K1 (phylloquinone) supplementation (500 μg) with calcium and vitamin D slows progression of coronary artery calcium (CAC) in older adults; overall intention-to-treat showed no CAC progression difference, but ad…
DOI: 10.3945/ajcn.2008.27338