Questions tagged [vitamins]

Questions regarding organic compounds required by an organism as a vital nutrient in limited amounts.

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72
votes
1answer
52k views

Why do Humans not produce Vitamin C like other mammals?

Why do most mammals produce their own Vitamin C? Why do Humans not?
23
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1answer
5k views

Can vitamin B17 cure cancer?

I have heard that a 'vitamin B17' can cure cancer, but that the medical industry never talks about it, since making it legal would cause them loss of billions. But I have never found a reliable report ...
13
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3answers
10k views

Is cancer caused by vitamin B17 deficiency?

I have read in an article on the internet that cancer is caused due to deficiency of vitamin B17 which has been removed from our diets long ago in the western food. But some people say that vitamin ...
9
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1answer
3k views

How can haired mammals synthesize vitamin D?

The human body can synthesize vitamin D in the skin from cholesterol, when sun exposure is adequate. But how can haired mammals do it? Do not they need it?
8
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1answer
2k views

Pasteurisation of orange juice and Vitamin C

In the UK at present, one of the examination boards has set a "controlled assessment" (an experiment that pupils do at school under exam conditions) that involves testing a hypothesis that vitamin C ...
8
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1answer
1k views

Why do Arctic predators accumulate vitamin A?

Top predators in the Arctic are known to accumulate vitamin A, often to levels that are toxic for human consumption. A 2012 study by Senoo, Imai, et al. found that the livers of several predator ...
7
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2answers
5k views

How is vitamin B12 stored in the body although it is water-soluble?

Vitamin B12 is stored in the liver for a long time. How is it stored?
7
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1answer
519 views

Counterintuitive action of Vitamin D?

Vitamin D acts in a way which to me is counterintuitive. It functionally supplemets Parathormone. It in the intestinal tract steps up calcium absorption by altering nuclear gene expression and also ...
6
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3answers
2k views

How is a substance classified as a vitamin?

From wikipedia A vitamin is an organic compound and an essential nutrient that an organism requires in limited amounts. There are many essential nutrients to an organism. Glucose for example. ...
6
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1answer
437 views

Can the absorption of vitamins be enhanced?

Are food additives like vitamins better absorbed when you mix them among fruits? I heard that secondary substances in fruit promote the absorption.
6
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1answer
470 views

Functionality of vitamin A, Bx, C, D, E, K as used in cosmetics for the skin?

I was wondering if someone can compare the functionality of vitamin A, Bx (x means numbers, such as 1, 2, 3, ...), C, D, E, K in the skin? They are used in cosmetics but what is their actual effect? ...
6
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1answer
2k views

Is it possible for a substance to be absorbed by the hair or the scalp?

I've heard that the aplication of Monovin A in the hair would allow it to grow faster. Monovin A seems to be only A vitamin, according to the first website. Could the application of A vitamin in the ...
6
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1answer
2k views

Are there any effects of elevated Cysteine levels on cognitive function?

I'm looking at this diagram of homocysteine metabolism and see two distinct pathways that the amino acid may get metabolized to: with vitamin B12 it gets converted back into methionine, while with B6 ...
5
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3answers
96 views

What's unique for vitamin B-12 group?

I've been trying to figure out what makes the vitamin B group really big with 8 vitamins. Chemically they have different structures. Solubility: not only vitamins from this group are water soluble ...
5
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2answers
118 views

What vitamins exist for other animals but not humans?

As you probably know, humans are among the minority of animals that require Vitamin C and don't produce it ourselves. For whatever reason (multiple theories exist), we lost the ability. Meanwhile, the ...
5
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5answers
3k views

Why can't you just take a vitamin? Why you need a healthy diet on top of that?

From what I understand, your body needs certain amounts of vitamins and minerals to maintain health. Why can't we just take enough pills to obtain these vitamins and minerals?
5
votes
1answer
6k views

What does vitamin B6 and B12 absorption depend upon?

I'm looking at my question about homocysteine metabolism and am doing a followup inquiry into vitamins B6(Pyroxidine) and B12(Cyanocobalamin). I've found this interesting bit about vitamin B12 and am ...
5
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1answer
427 views

Why plants (eg. parsley) can keep vitamin C despite all the sun?

I have read that vitamin C is highly sensitive to light. So, how could parsley, for instance keep its vitamin C as it's flooded with sunlight?
5
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1answer
316 views

What biological systems are affected by Vitamin B6 (or B vitamins in general)?

B vitamins and particularly the B6 vitamin appears to the one of the main ingredients in energy drinks. There has been anecdotal evidence from people interested in dreaming that ingestion of vitamin ...
4
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1answer
759 views

How many almonds a day can cause toxicity for vitE?

Vit E in high doses is dangerous for tissue. How many almonds a day taken regularly can cause this? RDA Males : 10mg/day Females : 8mg/day Pregnancy : 10mg/day Lactation : 12mg/day 15 mg = 33IU for ...
4
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1answer
211 views

In theory, would it be possible to create an injection of Vitamins, Minerals, sugars etc so that eating was no longer necessary?

I am wondering, out of pure curiosity, whether with current medical & biological science, (or indeed with accepted probable future developments in those areas), in theory, would it be possible to ...
4
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1answer
496 views

Effect of heat-treatment of Vitamin C

When it is in the body, does it matter if vitamin C has peviously been heat-treated? Can the body still use it? For instance, if vitamin C is added to 90 degree celsius water does it matter if you ...
3
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2answers
2k views

Vitamins. How they got their names?

There are several types of vitamins. A,B,C,D,E,H,K,P, etc. etc. So how they got their names?
3
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2answers
268 views

What is the definition for vitamins?

I have found the following definition on Wikipedia: An organic chemical compound (or related set of compounds) is called a vitamin when the organism cannot synthesize the compound in sufficient ...
3
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1answer
85 views

How does the inability to produce vitamin C helped weight gain?

I recently wondered how do dogs cope without vitamin C intake like us. A few Wikipedia pages later, I learned that our dry-nosed ancestors lost about two-thirds of the gene responsible for vitamin C ...
3
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0answers
111 views

Can the Human body Synthesise Vitamin D from Phytosterols?

I know that the human body can synthesise vitamin D from cholesterol, but can it do so from phytosterols?
2
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1answer
511 views

Is it possible that there are unknown vitamins?

Is it possible that there are vitamins or other essential nutrients about which we still do not know?
2
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1answer
265 views

How could 45 milligrams of a substance equal 4,500 micrograms? [closed]

In this book, the author repeatedly states that 45 milligrams of vitamin K2 equals 4,500 micrograms. I thought 1 mg = 1000 mcg. How could this be?
2
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1answer
136 views

Vitamins that could help “make us smarter”? [closed]

I was at Sprouts health store and saw a lot of vitamins/herbs that claimed to be "Study Aids" etc, so if there is any basis to it, where exactly does it hold truth? And are these supplements safe?
2
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1answer
579 views

Is vitamin D a vitamin or a hormone?

Some people like to say that vitamin D is a hormone. A simple set of differences between hormones and vitamins is described here. Vitamin D is not (for the most part) absorbed through food but ...
2
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1answer
510 views

Why do provitamins-A do not cause Vitamin-A toxicity?

Why do beta-carotene and other provitamins like alpha-carotene not cause vitamin-A toxicity but rather carotenosis (Orange skin) whereas retinal, retinol, and retinoic acid cause vitamin A toxicity ...
2
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1answer
38 views

What happens to intrinsic factor exactly at the terminal ileum, where B12 is absorbed?

IF is very important for IF-dependent B12 absorption in the terminal ileum, the mechanism by which most of dietary B12 is absorbed. The B12-IF complex bind to IF receptors on enterocytes, but does the ...
2
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1answer
62 views

Do vitamins help our memory?

It is commonly believed that vitamins can help our memory. Is this really true? What is the biological basis of this? Is there any specific research paper on the subject?
2
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1answer
152 views

What is the role of Homocysteine in cognitive function?

I'm looking at this link : Homocysteine and cognitive impairments and am looking for more information on specific cognitive impairments associated with elevated levels Homocysteine. That article is ...
2
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1answer
309 views

Do You Need Vitamin B12 To Utilize Folate

Just wondering if Vitamin B12 is necessary for the body to utitlize folate. My husband is on Methotrexate for rheumatoid arthritis, a medicine which is known to destroy folate. The doctors therefore ...
2
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1answer
87 views

The human organism knows what we have to eat? [closed]

My mother has told that if your organism needs a vitamin, you want fruits include that vitamin. For example you have lack of C-vitamin you would like to eat lemon. Is there any explanation for it, or ...
2
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1answer
104 views

Effects of having too much vitamin D?

I saw there was another question about vitamin D; however, I do not believe this is a repeat. What are some of the effects/side effects of having too much vitamin D in your body?
2
votes
1answer
100 views

How essential is vitamin B3 to the diet?

I know this might seem contradictory since by definition a vitamin is an essential part of the diet but I have read that nicotinamide, a form of vitamin B3, can be synthesised from L-tryptophan. Is it ...
2
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0answers
26 views

A question about dicumarol

I know that dicumarol was discovered in moldy sweet clover as it caused hemorrhage in cattles, but if someone had thromboembolic disorders causing uncontrolled thrombosis,would it be fine to eat moldy ...
2
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0answers
135 views

How long does it take for Vitamin D3 to have physiological effect

As far as I understand Vitamin D3 has no direct physiological effect but has to be first converted. If a person if given a mega-dosis. (50000-200000 IU) of Vitamin D3, how long does it take till the ...
1
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2answers
127 views

Rampant low Vitamin D

Why have people inadequate vitamin D status? Is it just (the lack of) sun exposure, or is it related to hormone and thyroid function?
1
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2answers
4k views

Is there enough vitamin B12 in lakes, rivers and ponds, for humans not to need to take supplements?

Vegans will often say that having an animal-free diet is best for our health and is actually the diet that humans should be eating to function optimally. To which meat eaters will raise the issue of ...
1
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1answer
126 views

Is the serum concentration of calcitriol different at different times in the day?

Given that calcitriol has a relatively short half-life in adults it would be possible that the serum concentration is at different times of the day different if it gets produced in different ...
1
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1answer
283 views

How does vitamin A deficiency arise?

How does vitamin A deficiency arise? I am living in a "developed" country, so excuse me if I miss some facts that are real, and threatening, in other parts of our world. I heard about https://en....
1
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1answer
147 views

Do vitamins protect you from common cold? [closed]

Do vitamins (taken as pills) boost your immune system, and make you less likely to contract diseases such as common cold or flu?
1
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2answers
551 views

Why does B12 deficiency enlarge red blood cells?

I'd like to know why B12 deficiency enlarge red blood cells
1
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1answer
618 views

Is there a correlation between B12 deficiency and cardiovascular disease?

I've read in several health sites that state that high blood homocysteine, as well as low B12 intake, is not only correlated, but actually causes cardiovascular diseases. In order to verify those ...
1
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1answer
61 views

Microbiome Context for Amino Acid Essentials and Non-Essentials

Given what we are now learning about the diverse mix and variance of microbiomes (aka bacterias via human gut project), is it possible that synthesis of aminos can be done by specific bacteria and ...
1
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1answer
116 views

Does vitamin C decrease after reacting with oxygen free radicals?

From the research that I have done, I know that antioxidants such as vitamin c donate electrons to oxygen free radicals and effectively neutralize them. They themselves do not become free radicals as ...
1
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0answers
58 views

Question about vitamin b6 product and cycling

Can the b6-product of a vitamin b6 reaction such as transaminase be recycled back to active vitamin b6 in man, and if so by means of what reaction?