Prof. Giorgi Pkhakadze, MD, MPH, PhD
Vitamin D3 + K2: Absorption vs Direction — How the Pairing Works
D3 decides how much calcium enters the body; K2-activated proteins influence where it ends up. What the combination evidence actually…
Who Is at Risk of B12 Deficiency: Older Adults, Vegans, Metformin and PPI Users
B12 deficiency clusters in four predictable groups — and its cruellest feature is that irreversible nerve damage can arrive before…
All-trans vs Cis MK-7: The Isomer Problem Most Supplement Labels Hide
Two MK-7 molecules can share a label claim while only one works: the all-trans isomer is biologically active, the cis…
MK-7 vs MK-4: Why Half-Life Decides the Dose
Two menaquinones, one decisive number: MK-4 vanishes from blood in hours while MK-7 circulates for days. That difference is why…
Why Exactly 100% NRV: Vitamin A’s Narrow Safety Margin Explained
For most vitamins, the gap between daily reference and safety ceiling is vast. For vitamin A it is 3.75× —…
Why High-Dose Oral B12 Is the Evidence-Based Dose
500 µg of B12 is 20,000% of the reference value — a number that looks like marketing until you learn…
K2 vs K1: Why Menaquinones Reach Bone and Blood Vessels
One vitamin, two destinations: K1 serves the liver's clotting factory, while K2 circulates long enough to activate the proteins that…
Vitamin A and Pregnancy: The Teratogenicity Warning Explained
Retinoic acid is one of the master signals of embryonic development — which is exactly why excess preformed vitamin A…