Cholecalciferol + Menaquinone · D3/K2 · Vitamin D + Vitamin K
Baseline hormone-axis support that amplifies GH secretagogue outcomes.
FDA
Approved
WADA
Not Listed
HALF-LIFE
~2–3 weeks (D3); days (K2 MK-7)
ROUTE
Oral
SCHEDULE
Daily
In Plain English
Baseline hormone-axis support that amplifies GH secretagogue outcomes.
Status & Legality
What do these mean?Hormone axis support
Calcium metabolism
Immune modulation
GH secretagogue adjunct
Vitamin D3 acts as a steroid hormone precursor, regulating over 1,000 genes including those involved in testosterone and GH signaling. K2 (MK-7) directs calcium deposited by D3 into bone rather than soft tissue. Most people running peptide protocols — especially GH secretagogues — are D-deficient without knowing it, which blunts the hormone-axis response. Testing and optimizing is a high-leverage, low-cost intervention.
Hypercalcemia only at very high doses (>50,000 IU long-term)
Nausea at doses >10,000 IU without food
K2 interaction with warfarin — caution
Excellent safety at recommended doses
Taking D3 without K2 long-term — D3 increases calcium absorption; K2 (MK-7) directs it into bone rather than soft tissue; the K2 is not optional
Not testing 25(OH)D before supplementing — baseline levels vary widely; some need 2,000 IU, others need 10,000 IU to reach optimal range (50–80 ng/mL)
Supplementing without fat in the same meal — D3 is fat-soluble; absorption drops significantly without dietary fat at the same meal
Warfarin — Vitamin K2 affects clotting cascade; monitor INR carefully if on warfarin
Thiazide diuretics — can cause hypercalcemia when combined with high-dose D3; monitor calcium
Calcitonin and bisphosphonates — generally safe; complementary bone health mechanisms
Test before supplementing D3 — about 40% of people are deficient at baseline, and the correct dose depends on your starting level. 5,000 IU D3 + 100 mcg K2 (MK-7) is the most common protocol, but genuinely deficient individuals may need more to reach optimal range. K2 is not optional for chronic high-dose D3 supplementation.
TESAMORELIN
FDA-approved GHRH analog — visceral fat reduction.
THYMOSIN ALPHA-1
Immune modulator — infection resistance and anti-cancer.
CREATINE MONOHYDRATE
Muscle-preservation insurance during GLP-1–driven weight loss.
Free, no account needed
Drop your email and we'll send the one-page starter checklist beginners actually need first. No account needed.
No spam, and we never sell your email. Just the checklist. Email support@pepvault.us to opt out any time.
Stats
Sources & Studies
Martineau AR. et al., BMJ, 2017