When it comes to sound nutrition: (see too the green type below)
(I copied this...): Vitamins are organic compounds which have to be obtained from the diet, either because an organism does not have the enzymes necessary to synthesize them or because it cannot produce them in sufficient quantities.
Humans cannot synthesize vitamins A, B1 (thiamine), B2 (riboflavin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folate), B12 (cobalamin), E and K but are able to synthesize some vitamin B3 (niacin) and D. (of course one also has to be careful not to do so much that dose becomes an issue of more than merely a loose stool which is the only adverse side effect of ascorbic acid)
The last vitamin required by humans, vitamin C (ascorbic acid), (it needs D3 to adequately implement it in the human body: https://www.youtube.com/watch?v=4TxpxfnLZNE video analysed and cataloged below) is a special case in that this organic compound is synthesized by the large majority of vertebrate and invertebrate species. Interestingly, the vertebrate organ used to synthesize vitamin C changed twice from the kidney to the liver during evolution, once in birds and once in mammals. Whereas vitamin C is produced by the kidneys of fishes, amphibians, reptiles, and older bird orders, it is produced by the liver of more recent bird orders and of mammals . This switch to a larger organ in more active species has been interpreted as being the result of selective pressures to maintain biochemical homoeostasis under more stressful conditions [2, 7]. This is reflected by the fact that the human daily recommended intake for vitamin C (60 mg) (still ridiculously and appallingly low, our vertebrate kin produce around a gram per 10 pounds of body weight per day until stressed when they can produce up to a gram a pound! ) is the highest among all vitamins [8, 9].
The above comes from this site which is pretty terse scientific data or you can continue read what I "cherry picked":
As you read here anything italicized and/or in parantheses is not their original content.
Vitamin C is a water-soluble compound with anti-oxidant properties that protects living organisms against oxidative stress. It is also essential for collagen synthesis,(new cells do not form without vitamin C) which is why insufficient amounts of this vitamin lead to scurvy (and unnecessary oxidative stress that leads to disease, "a disorder of structure or function",). Its other functions include the synthesis of carnitine, neurotransmitters and the catabolism of tyrosine, among others.
...no species (except we humans) lacking GLO activity (the ability to internally synthesis our own ascorbic acid) has ever been found to have a diet poor in vitamin C.
Life altering revelations about the function of D3 and ascorbic acid in white blood cells:
Here's a cataloged list pertaining to subject and minute discussed:
1:00 D3 known to regulate 2776 genes,
2:40 when deficiencies coexist with diseases:
those diseases present sooner rather than later,
are more severe rather than less severe,
and the treatments for the diseases are less effective until you have identified the coexisting deficiencies and corrected them!
3:35 most people are D deficient and
"you have to be C deficient" because we can't make it!!! you only get what you intentionally put in and you are not putting it in!!!
5:00 because we can't make it (C) we have to have a significant reserve...not having a reserve, (not continuously having it saturating our system) is why we have trouble in the first place...
6:35 Can humans make vitamin C as a hormone? YES...
10:00 5,000 IU is now a common dose of D3 but you need 10,000
13:35 Iodine unloads almost all the heavy metals...
everybody is iodine deficient!!!...
14:10 self monitoring is the way most things will go, you can get a test kit from... I looked on Amazon and they're pretty expensive. I'd say just do the 10,000!!!
15:50 What happens when our demand for vitamin C goes way up?
16:05 How can you survive with a ZERO plasma level of vitamin C?
17:40 If you want to have a good C level it's imperative that you have a good D3 level. Shoot for 80 ng/ml.
D3 amplifies glutathione production
18:15 The only place vitamin C is safe is in the white cells because we don't pee out white cells. White cells are what carry vitamin C to target.
19:13 All mammals have a glutathione mechanism to recycle vitamin C.
19:30 Linus Pauling
20:05 When D3 amplifies a gene that's good for us... D3, the Guardian
21:08 Intravenous C should be our model (liposomally encapsulated C has a higher absorption rate than intravenous!!!)
21:55 Ten subjects.
I literally wept when I heard about the Atlanta 1000 bed trauma center and the results of enlightened use of vitamin C. If you aren't moved to action upon hearing such a revelation I don't know what else to say or do.