Comparison
Vitamin D3 vs Vitamin K2 (MK-7)
Vitamin D3
Hormone-like vitamin synthesized in skin from UVB. Profoundly involved in brain function, mood, and inflammation.
Vitamin K2 (MK-7)
MK-7 form has longest half-life and best cardiovascular evidence. Pair with vitamin D3.
| Field | Vitamin D3 | Vitamin K2 (MK-7) |
|---|---|---|
| Category | vitamin | vitamin |
| Dose range | 0.025–0.125mg | 0.05–0.18mg |
| Half-life | 360h | — |
| Onset | — | — |
| Evidence | EVIDENCEA | EVIDENCEB |
| Safety | ●●●●● | ●●●●● |
| Legal (US) | USOTC | USOTC |
| PubMed refs | 9200 | 1200 |
The comparison in plain English
Auto-generated from dataVitamin D3 and Vitamin K2 (MK-7) are both in the vitamin category respectively. Vitamin D3 Hormone-like vitamin synthesized in skin from UVB. Vitamin K2 (MK-7) MK-7 form has longest half-life and best cardiovascular evidence.
Bottom line
Vitamin D3 (evidence A, safety 5/5) has a weaker evidence base than Vitamin K2 (MK-7) (evidence B, safety 5/5). Vitamin D3 has the slightly cleaner safety profile. For users new to either, the higher-evidence option is the safer first try.
Choose Vitamin D3 if
Vitamin D3 is the better fit when your goal aligns with its mechanism (Vitamin D3 (cholecalciferol) is converted to 25-hydroxyvitamin D in the liver and then to the active hormone 1,25-dihydroxyvitamin D (calcitriol) in the kidneys) and the dose range (0.025–0.125mg) suits your protocol. Half-life is 360h.
Choose Vitamin K2 (MK-7) if
Vitamin K2 (MK-7) is the better fit when your goal aligns with its mechanism (Vitamin K2 (menaquinones) is the cofactor for gamma-carboxylation, the enzymatic step that activates matrix Gla-protein (which directs calcium away from arterial walls toward bones) and osteocalcin (which incorporates calcium into bone matrix)) and the dose range (0.05–0.18mg) suits your protocol. Half-life is —h.