Vitamin B6 (P5P) vs Vitamin K2 (MK-7)

Mechanism

Pyridoxal-5-phosphate (P5P) is the active coenzyme form of vitamin B6, required by over 150 enzymes. Key roles: transamination and decarboxylation of amino acids, serving as a cofactor for aromatic L-amino acid decarboxylase (converting 5-HTP to serotonin and L-DOPA to dopamine), glutamic acid decarboxylase (producing GABA), cystathionine beta-synthase (homocysteine transsulfuration to cysteine), serine hydroxymethyltransferase (one-carbon folate metabolism), glycogen phosphorylase (glycogenolysis), and aminolevulinic acid synthase (heme synthesis).

Standard Dosing

25-50mg P5P daily

Timing

Morning with food. Often included in B-complex.

Cycle Duration

ongoing

Side Effects

• Peripheral neuropathy at chronic doses >200mg/day (numbness, tingling)
• Photosensitivity
• Nausea
• Vivid dreams

Contraindications

• Levodopa monotherapy
• Doses >200mg/day chronically (peripheral neuropathy risk)

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Mechanism

Vitamin K2 (menaquinone-7) activates vitamin K-dependent proteins via gamma-carboxylation of glutamic acid residues. Key targets: osteocalcin (directs calcium into bone matrix), matrix Gla protein (MGP, inhibits arterial calcification), Gas6 (cell signaling, neuroprotection), and protein S (anticoagulant). MK-7 has a long half-life (~72 hours vs 1-2 hours for K1) enabling consistent carboxylation activity with once-daily dosing. It works synergistically with Vitamin D3 to regulate calcium metabolism — D3 increases calcium absorption while K2 directs its deposition.

Standard Dosing

100-200 mcg MK-7 daily

Timing

With fat-containing meal alongside Vitamin D3.

Cycle Duration

ongoing (mandatory co-supplement with Vitamin D3)

Side Effects

• Generally very well tolerated
• Rare: mild GI discomfort
• Theoretical thrombotic risk in deficiency-rebound scenario (unproven)

Contraindications

• Warfarin/coumarin anticoagulant therapy (unless specifically directed by physician with INR monitoring)

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