@OrpingtonClose said in Whats the deal with "Vitamin" A?:
Is it good or bad?
Here is some info I collected through my decoder
Note that all people won’t agree with what follows.
*) ## High intake of vitamin D (5 000 UI) or a deficiency of Retinol
An excessive intake of vitamin A (retinol) can cause a deficit of Vit D by antagonism. U-shape activity. Retinol (the active form of vitamin A) is an antagonist of vitamin an excess or a deficiency of one or the other of these vitamins will counteract the functioning of the VDR receptors, leaving them unoccupied or inactive.
Moreover “Any intracellular capable of producing a substance that blocks the VDR would have an effective strategy for disabling the immune system!”
https://mpkb.org/home/pathogenesis/vitamind/metabolism
Excerpt: Bacteria and the VDR
Hormonal changes result from change in 1,25 dihydroxyvitamin-D
*) Technical explanation, in short.
An excess of vitamin A (or a vitamin D deficiency) prevents the formation of heterodimers: essentially homodimers (RXR-RXR) will be formed, leaving the VDR unoccupied and inactive.
Source: Zoëhlo (French Pharmacologist)
*) I eat once a week 2 chicken livers (lightly roasted, with one onion), in 250 ml soup. Or I take 10 000 UI retinyl palmitate (once softgel) with a meal (fat required).
It’s not a good idea to take more than 3 000 mcg in once. The Tolerable Upper Intake Level (UL) for adults is set at 3,000 μg/day. Most vitamin A is stored in the liver. ## The half-life of vitamin A is estimated to be 128 days, so it can take many months for retinol levels to normalize after vitamin A toxicity. (4)
10 000 UI = 3 mg = 3 000 mcg
Conversion :
*) Retinol: UI in mcg => x 0.33.
6 000 of retinol Estroban x 0.33 = 1980 mcg.
4. Institute of Medicine (US) Panel on Micronutrients
Dietary reference intakes for vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc. Washington, DC: National Academies Press (US); 2001. Google Scholar
*) Vitamin A has effects of thyroid hormone
Vitamin A lowered TSH and increased T3 in both lean and obese humans. “The effects of vitamin A supplementation parallel the effects of supplementing T3 - i.e. lower TSH and T4 and higher T3 levels”. Haidut
http://www.ncbi.nlm.nih.gov/pubmed/23378454
*) ## Interaction between fat-soluble vitamins
Vitamin K2 is the substance that allows dependent proteins A and D to be activated / come to life. While vitamins A and D act as signaling molecules, indicating to the cells to produce certain proteins, vitamin K2 activates these proteins by giving them the physical capacity to link calcium.
In order to truly understand the fat-soluble vitamins, however, we must understand that vitamins A, D, and K cooperate synergistically not only with each other, but also with essential minerals like magnesium and zinc, with dietary fat, and with key metabolic factors like carbon dioxide and thyroid hormone.
Useful info:
https://mirzoune-ciboulette.forumactif.org/t2017-english-language-corner-1-liposoluble-vitamins#29442
https://mirzoune-ciboulette.forumactif.org/t667-vitamine-a-sous-estimee#5923 (studies links)
The greatest use of vitamin A is at the level of production of pregnenolone, progesterone and the other steroid hormones associated with youth.
“Vitamin A is for the production of pregnenolone, progesterone, and the other youth-associated steroids”. http://raypeat.com/articles/articles/alzheimers2.shtml