75

Humans do not produce Vitamin C due to a mutation in the GULO (gulonolactone oxidase) gene, which results in the inability to synthesize the protein. Normal GULO is an enzyme that catalyses the reaction of D-glucuronolactone with oxygen to L-xylo-hex-3-gulonolactone. This then spontaneously forms Ascorbic Acid (Vitamin C). However without the GULO enzyme, ...


42

Laetrile/Amygdalin has been claimed to be a suitable treatment for 'cancer' (which is a summary term for an extremely heterogeneous class of diseases). Even though laetrile/amygdalin in these claims is often called a vitamin, it in fact is not a vitamin as the molecule is not essential for the metabolism (Greenberg (1980)). The claimed effects of laetrile/...


21

Short Answer: No. Background: First of all, there is no such thing as vitamin B17. The compound, amygdalin or laetrile, which is referred to by this term, is not a vitamin1. Amygdalin is indeed a cyanogenic glycoside (like glucosinolates, see this answer) which is poisonous to organisms including humans, because it forms cyanide which is toxic2. See this ...


14

Short version: This is nonsense, cancer does not arise from nutritional deficiencies. Long version: The substance is called Amygdalin, a poisonous cyanogenic glycoside. It can be found in higher concentration in the kernels of several plants including apricots, plums, bitter almonds, peach, plum. The semisynthetic, modified form is called Laetrile. Taking ...


10

Vitamin B12 (cobalamin) is a cofactor required by the enzymes methionine synthase (MTR) and methylmalonyl-CoA mutase (MUT). These are the only known enzymes that use B12 in humans, and are abundant in the liver. Since it is a cofactor, B12 is not consumed by any reactions, and hence there is no need to store large amounts of B12 beyond that bound to MTR and ...


9

Hodgins AM, Mittal GS, Griffiths MW. 2002. Pasteurization of Fresh Orange Juice Using Low-Energy Pulsed Electrical Field. J Food Sci 67(6):2294-2299 This is a study of non-thermal food preservation, but it cites two studies that measured ascorbate loss from pasteurisation. I can't cite the studies directly because I can't find them online. According to ...


6

There are two types of vitamins: Fat soluble vitamins - Vitamins A, D, E, K Water soluble vitamins - B complex Vitamins and Vitamin C Fat soluble vitamins get better abosorbed when fat content of food is good. The bile secretion is also very important. These vitamins form miscelles with the fat molecules and get absorbed as such. The absorption of these ...


6

The quantity of nutrients the body requires takes much more physical space than can be included in a simple pill or injection (used only a few times a day). But nutrition can be provided by IV (intravenous administration), and it is used today for some medical conditions. When the IV completely substitutes for normal digestion, it is called total ...


6

There are two pieces to this question: a) How does bone resorption (movement of Ca/Phos out of bone into the blood) result in net improvement in bone structure? Bones are constantly remodeling, primarily in response to mechanical stressors. Although you clearly already realize this, I will make it explicit: osteoblasts are the cells that create new bone; ...


5

I think the piece of missing information here is the distinction between macronutrients and micronutrients. The info from Mayo clinic quoted in the another answer addresses some reasons why whole foods might be better than pills for obtaining micronutrients (i.e. vitamins and minerals). While this may be true, most of it remains to be conclusively ...


5

As to the subject line, yes, lipid substances or any non-polar small molecule will enter the skin cells and the body below. The reason is because cell membranes simply consist of fatty substance that behaves like a solvent for other lipids. As to the specific question about this product, Monovin A. This is a veterinary product and the producer, Laboratórios ...


5

Vitamin A: One study conducted in the 60's claims that vitamin A acid prevents formation of comedones in Acne Vulgaris [1]. Another one conducted in the 70's found no significant improvement of plantar warts when vitamin A acid was applied topically [2]. Vitamin D: Agents like calcipotriene associated with topical steroids are effective against psoriazis [3]...


5

B12 is stored as mitochondrial 5-deoxyadenosylcobalamin, primarily in the liver (2 to 5 mg) but also about another 1/3rd in muscle. It's estimated that 0.1% of reserves are turned over per day, and the reference values for serum B12 are 180 to 914 ng/L. While the literature tends to use the term "storage," this coenzyme form of B12 would still be taking an ...


5

1) Vitamin D is a bit of an umbrella term that actually refers to a whole group of related molecules. One of these, vitamin D$_3$ (cholecalciferol) is formed spontaneously from ergosterol in the presence of UV radiation, which happens in the skin when exposed to sunlight. Cholecalciferol is then converted to calcitriol, the active form, in the liver. Here is ...


5

Yes, it is possible that there is a vitamin or other essential nutrient that has not been identified so far. Essential nutrient means any substance normally consumed as a constituent of food which is needed for growth and development and/or the maintenance of life and which cannot be synthesized in adequate amounts by the body (fao.org). Essential nutrients ...


5

The common scientific belief around 1900 was that the only dietary components needed to support life were protein, fats, carbohydrates, and salts.[1] In 1912 Hopkins reported on experiments showing that "accessory factors" seemed to be needed.[1] In 1916, some of the factors began to be characterized in the paper "The Relation of the Unidentified Dietary ...


4

Vitamin B12 (cobalamin) is a water-soluble vitamin required for homocysteine methyltransferase. In order to be absorbed, it must bind to intrinsic factor (IF), which is produced by the parietal cells of the stomach. The absorption of the vitamin B12-IF complex occurs in the terminal ileum (of the small intestine). The quote just means that if there isn't ...


4

Are there vitamins that make us smarter? Vitamins are micronutrients required in small quantities for normal human metabolism. Extra high (supra-physiological) doses do not generally result in improved performance. Of course, if one is deficient in certain vitamins (e.g. Vit B-1 deficiency causing Wernicke-Korsakoff encephalopathy), taking a vitamin can ...


4

Here in Australia there are more cases of vitamin D shortage than in England. Given the double amount of sun hours per annum here in Down Under, that's quite counter intuitive. In fact, an estimated 31% of adults in Australia have inadequate vitamin D status, increasing to more than 50% in women during winter–spring and in people residing in southern states (...


4

This is a typo. In the text he states: ... only 0.120 milligrams (120 micrograms) of MK-4 ... So, he knows the correct conversion. Then: ... the "same" product is almost 40 times more potent in one country ... 40 times 120 micrograms is 4800 micrograms -- which is close to 4500. So, that suggests that the (4,500 micrograms) in the table is ...


4

They were more or less named in the order that they were found. Letters F-J are skipped because many of those were reclassified or later found not to be vitamins. The K comes from the German word for Koagulation because the vitamin is involved in the coagulation of blood. The discovery dates of the vitamins and their sources / Year of discovery /Vitamin ...


4

Disclaimer: the denaturation is the process of protein unfolding from their native state. Since vitamin C is not a protein, it cannot denaturate. I think that the word you're looking for is simply "degradation". Vitamin C can exist either in its reduced form L-ascorbic acid (L-AA) or in the oxidised form dehydroascorbic acid (DHAA). The active (antioxidant) ...


4

According to PeaceHealth: The vitamin B-complex refers to all of the known essential water-soluble vitamins except for vitamin C. Vitamin B was once thought to be a single nutrient. Researchers later discovered these extracts contained several vitamins. Each member of the B-complex has a unique structure and performs unique functions in ...


3

Generally speaking, bulk essential nutrients (e.g. amino acids, fatty acids) are used stoichiometrically to form macro cellular structures and are 'baked in' to the structures or compounds they are used to make. Once those structures are destined for degradation, sometimes the bulk essential nutrients can be recovered and reused in the synthesis of other ...


3

Since, you didn't state whether you were referring to a concentrate or not, i'm assuming the following forms of Vitamin A were obtained via pill or topical suspension - except for the Carotenoid. α-carotene and β-carotene are (primary) precursors to Vitamin A. Likewise with, Retinal, Retinol but not with Retinoic Acid (irreversibly metabolized/end point) ...


3

UV light promotes the photo-oxidation of ascorbic acid (AsA) to dehydroascorbic acid (DHA). DHA can be reduced to AsA by a specific dehydrogenase using reduced glutathione as reductant. I'm pretty sure that all cells are able to carry out this recycling of ascorbate. Interestingly, in plants it appears that ascorbate acts as an electron donor to ...


3

The main effect, of vitamin B6, is neurological, becouse moderate variations in the intracellular concentration of pyridoxal 5'-phosphate (PLP), the biologically active form of vitamin B6, can have pronounced modulatory effects on steroid-induced gene expression. So you cannot get the effect of stress hormones. Also neurological damage has been reported ...


3

Your shown homocysteine pathway is way too simple. Especially the production of the neuromodulator H2S from excess sulfur amino acids is not shown. In the last years many more enzymes and reactions have been discovered. I have summarized human sulfur amino acid metabolism in reactome.org, so please use this link to discover all the details and new papers. I'...


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