@RayPeatFan said in Vit E and Vit K:
Where is the study that claims HD Vit K could contribute to Vit E deficiency?
No deficiency but possibly preventing from assimilation. No clear proof.
Most studies establish the fact that we should avoid HD vit E (> 300 UI) when taking vitamin K, especially K1. It makes sense (conversion to MK4 more complicated). But that's not this aspect I mentioned. I'm talking about HD MK4 supplement with 400 UI vitamin E.
So, studies establishing why or at least mention the advice we shouldn’t take Vit E at the same time as HD K2.
Mechanisms according to MG Traber (deduction)
https://academic.oup.com/nutritionreviews/article-abstract/66/11/624/1868525?redirectedFrom=fulltext
Vitamins E and K appear to share the same metabolic pathways because both undergo side chain ω- hydroxylation and b-oxidation to produce their respective metabolites.
Possible mechanisms for the vitamin E and K interaction
*) Vitamins E and K share the same metabolic pathways
*) Vitamin E competes for the enzyme (yet undiscovered) that truncates the K1 side chain to form menadione;
*) Vitamin E increases xenobiotic pathways that increase the metabolism and excretion of all vitamin K forms from the liver;
*) Vitamin E competes with K1 for the cytochrome P450 (CYP) that ω-hydroxylates the tail, thereby preventing the b-oxidation of the tail to form menadione. The latter mechanism is hypothetically less likely because, as discussed by Thijssen et al. (11), there is likely to be steric hindrance preventing the complete removal of the K1 side chain via b-oxidation for menadione formation. All of these mechanisms would decrease the production and/or availability of MK-4. The hypothesis that vitamin E interferes with the conversion of K1 to MK-4 is supported by the observations that MK-4 concentrations in extrahepatic tissue are lower in rats fed a high vitamin E diet.
