OnePin Peptide Library · Metabolic
Vitamin D3 + K2
D3/K2 · Cholecalciferol + MK-7 · D3 K2
Vitamin D3 (cholecalciferol) is a fat-soluble secosteroid hormone precursor essential for calcium homeostasis, immune function, and hundreds of downstream gene-regulatory effects. Vitamin K2 (menaquinone, specifically MK-7 and MK-4 forms) is a fat-soluble cofactor essential for activating matrix Gla protein (MGP) and osteocalcin - proteins that direct calcium INTO bone and AWAY from arterial walls. The two vitamins are almost always co-supplemented because D3 increases calcium absorption and K2 determines where that calcium deposits.,Vitamin D deficiency is extraordinarily common - meta-analyses suggest 40-60% of adults in northern latitudes have serum 25(OH)D <30 ng/mL (deficient or insufficient). Modern indoor lifestyles, sunscreen use, obesity (vitamin D sequestration in adipose tissue), and darker skin pigmentation all contribute. Adequate vitamin D status is associated with better immune function, bone health, muscle strength, mood, and reduced all-cause mortality.,K2 supplementation without D3 is less commonly indicated (dietary K2 from natto, aged cheeses, egg yolks is usually adequate), but co-supplementation prevents the theoretical concern of D3-driven calcium causing vascular calcification in the absence of K2. The MK-7 form of K2 has a 72-hour half-life vs MK-4's 1-hour half-life, making MK-7 dramatically more efficient for daily or twice-weekly dosing.
Take with a fat-containing meal (fat-soluble vitamins require fat for absorption). Test 25(OH)D after 8-12 weeks to titrate dose. Typical target: 40-60 ng/mL.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
How it works
Vitamin D3 is hydroxylated in the liver to 25-hydroxyvitamin D (calcidiol, the storage form measured in blood tests) and then in the kidneys and peripheral tissues to 1,25-dihydroxyvitamin D (calcitriol, the active hormone). Calcitriol binds the vitamin D receptor (VDR), a nuclear receptor expressed in virtually every tissue, and regulates transcription of >1,000 genes involved in calcium homeostasis, cell growth/differentiation, immune function, and antimicrobial peptide production (cathelicidin).,Vitamin K2 activates vitamin K-dependent proteins via gamma-carboxylation of glutamate residues. The key K2-dependent proteins are: (1) osteocalcin - binds calcium and incorporates it into bone hydroxyapatite, (2) matrix Gla protein (MGP) - prevents calcium deposition in arteries and soft tissues, (3) Gas6 - supports cell survival and phagocytosis. Without K2, these proteins circulate in inactive (uncarboxylated) form and calcium can deposit in inappropriate locations.,The D3+K2 synergy is mechanistic: D3 increases calcium absorption from the gut and mobilization from bone. K2 then directs that calcium into bone (via osteocalcin activation) and prevents arterial deposition (via MGP activation). The Rotterdam Study demonstrated this: high K2 intake was associated with 50% lower cardiovascular mortality and 57% lower arterial calcification.
Vitamin D3 is hydroxylated in the liver to 25-hydroxyvitamin D (calcidiol, the storage form measured in blood tests) and then in the kidneys and peripheral tissues to 1,25-dihydroxyvitamin D (calcitriol, the active hormone). Calcitriol binds the vitamin D receptor (VDR), a nuclear receptor expressed in virtually every tissue, and regulates transcription of >1,000 genes involved in calcium homeostasis, cell growth/differentiation, immune function, and antimicrobial peptide production (cathelicidin).,Vitamin K2 activates vitamin K-dependent proteins via gamma-carboxylation of glutamate residues. The key K2-dependent proteins are: (1) osteocalcin - binds calcium and incorporates it into bone hydroxyapatite, (2) matrix Gla protein (MGP) - prevents calcium deposition in arteries and soft tissues, (3) Gas6 - supports cell survival and phagocytosis. Without K2, these proteins circulate in inactive (uncarboxylated) form and calcium can deposit in inappropriate locations.,The D3+K2 synergy is mechanistic: D3 increases calcium absorption from the gut and mobilization from bone. K2 then directs that calcium into bone (via osteocalcin activation) and prevents arterial deposition (via MGP activation). The Rotterdam Study demonstrated this: high K2 intake was associated with 50% lower cardiovascular mortality and 57% lower arterial calcification.
What to expect
Weeks 1-4: Blood levels rising but subjective effects minimal. Test 25(OH)D after 8 weeks.
Evidence
Interactions & stacking
What's safe to combine, and what belongs in a separate pin.
Safe & synergistic
Keep separate
Pharmacokinetics
Storage. Store at room temperature (20-25C) in a cool, dry place. Protect from light. Capsules/softgels shelf-stable 2+ years. Liquid D3 drops stable when capped tightly. Both D3 and K2 are fat-soluble and stable in oil carriers.
Regulatory status
Classified as dietary supplements in the US - no prescription required for typical doses. Vitamin D is available as prescription at 50,000 IU (ergocalciferol D2 or cholecalciferol D3) for deficiency correction. K2 has no prescription equivalent.
Put it to work
Calculate, log & track
Open Vitamin D3 + K2 straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
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The guide & community
The complete Vitamin D3 + K2 walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
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