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

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49
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1answer
13k views

Why do Humans not produce Vitamin C like other mammals?

Why do most mammals produce their own Vitamin C? Why do Humans not?
7
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1answer
136 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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1answer
56 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
948 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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1answer
900 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 ...
5
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1answer
600 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?
5
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1answer
167 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
492 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 ...
4
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4answers
227 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?
4
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1answer
164 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? ...
4
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1answer
190 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?
4
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1answer
2k 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 ...
3
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1answer
127 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 ...
3
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0answers
61 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
59 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
58 views

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

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
44 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
67 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
54 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
45 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
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1answer
47 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 ...
1
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0answers
101 views

Were we able to create vitamin B12 in past?

All herbivores produce vitamin B12 de novo. Gorillas, for example, are "vegans" so I suppose some human ancestor was also herbivore. Have we ever been B12 self-producers? If so, why have we lost that ...
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0answers
46 views

Nutritious protein substance for vitamin enhanced crop?

I am not a bio or science major, but we have a subject, like an elective on biotechnology and we were tasked to think of a product that hasn't been invented yet. My groupmates and I thought of a ...
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0answers
50 views

Vitamin D oral intake, transportation and absorption

Several factors affecting vitamin D and its active form absorption and storage acidity of stomach (not significant effect) cytopathic effects of viruses cytopathic effects of bacteria where the ...
0
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1answer
39 views

Distribution of nutrients throuought a drink made of plants?

In an attempts to eat my veggies for the day in one shot, I blended together a bag of salad with some water. The mixture separated by density, a thick top layer containing the bits of leaves, and a ...
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0answers
35 views

Are vegetables really needed in our diet?

I want to believe that eating vegetables is necessary even when one takes vitamins, but I can't find any medical evidence for this. To make my question specific, suppose a study on twins were done in ...