The study of the appropriate provisions required to sustain life in an organism or the provisions themselves.

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21
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2answers
2k views

Why is it advised that infants are fed mother's milk?

I have heard that mother's milk is preferred over other baby foods, because it contains immunoglobulines (secretory IgA), and other essential nutrients. But why is mother's milk so special? Any ...
14
votes
2answers
233 views

Relationship between our microbiome and personalized nutrition

Recently, it has been asked whether there are 'metabolic types' between humans that can benefit from a sort of personalized nutrition. One answer suggested that one discerning factor could be the ...
12
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1answer
19k views

What is the composition of human feces?

Are there any studies or general information on the composition of human feces? I'd specifically like to know the percentage of carbohydrates and amino acids relative to the amount that was ingested ...
11
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4answers
2k views

Has there ever been an attempt to create nutritionally tailored food for adult human consumption?

For all domestic animals, and for all animals kept in laboratory, complete and precise composition of perfect food is figured out (cat food, dog food, cattle, rats, laboratory monkeys and apes) -- ...
11
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2answers
6k views

Can humans transdermally absorb minerals from ocean water, and if so how much?

According to several studies quoted here, chemicals can be absorbed by the skin transdermally, at least under certain conditions. When it comes to elements in seawater like sodium, magnesium, ...
10
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2answers
155 views

Do macrophages get nutritional value from the pathogens that they eat?

X-posted on reddit AskScience here. I know that macrophages engulf foreign bodies and transport them to various waste excretion pathways (sorry if the terminology is wrong), and if the foreign bodies ...
9
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1answer
164 views

What are the survival limitations of alcohol?

This question was inspired by watching one of the Pirates of the Caribbean movies; particularly where Jack Sparrow allegedly survives on a desert island by finding an unlimited supply of rum. I've ...
8
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1answer
115 views

Why do humans require vitamin B12 supplementation while herbivores do not?

This question came about from reading the comments of this (very unclear) question, which the author did not properly clarify. Vegans are often recommended to take vitamin B12 supplements, as the ...
7
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2answers
398 views

Why do carnivores evolve?

If humans can live without consuming other animals, then why we do it; from a biological point of view, why do we eat meat? I would also extend the question to another animals, because many animals ...
7
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2answers
170 views

Is cyanocobalamin toxic?

I see that cyanocobalamin is not naturally occurring, and is synthesized in vivo to methylcobalamin. As part of the synthetic pathway, cyanide is broken off. All opinions I can find are that this ...
7
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1answer
82 views

Do blood glucose “spikes” contribute to insulin resistance, or is prolonged elevation required?

There's increasing public discussion about the health risks of chronic insulin resistance* (IR). In many cases there's a focus on high glycemic index foods that "spike" your blood sugar, which implies ...
7
votes
2answers
265 views

How was the guided daily amount (GDA) calculated?

We are constantly shown nutritional information on food packaging stating this food contains "x" amount of your guided daily amount. A linked to the values is here. How were these values calculated? ...
6
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2answers
225 views

Tap vs. mineral water for drinking

I was told a human should drink a small glass (0,3 liter) of mineral water per day to get the minerals. What is the rationale behind this? What is the difference between tap water and mineral water in ...
6
votes
3answers
108 views

laboratory mice, nutrition, and humans

It seems that many nutrition experiments [directed at human diet] are carried on laboratory mice. Is there any justification that nutrition that is good or bad for laboratory mice will also be same ...
6
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2answers
341 views

Is there a biological reason for spreading food intake into breakfast-lunch-dinner?

I keep hearing over an over how humans can satisfy their entire daily caloric need in one sitting at a fast food restaurant. At the same time I'm looking at the kitchen plates, cups, etc, and they ...
6
votes
1answer
2k views

Powdered meal replacement vs regular meal

Can a person live with this alternative nutrition? Of course, assuming that eating pleasure is assumed the same. The nutrients that contain are far better than average meal a person eats the majority ...
6
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2answers
197 views

Do omnivore mammals vary food preferences based on dietary needs?

I'm wandering if mammals that can eat many different kinds of food (omnivores) vary their preference for food not only based on the availability, but also based on dietary needs? I'm looking at this ...
5
votes
3answers
117 views

Where can you find the quantities of each amino acid of a particular protein or food?

Taking a potato as an example. If I wanted to know how much µg or % of each of it's amino acids there are in 1 gram of pure potato protein, where can I find this information? Is there a freely ...
5
votes
1answer
193 views

What are 'acid stable' amino acids?

I tend to see terms amino acid, acid stable amino acid, and free amino acids used often in ...
5
votes
1answer
211 views

Possible to Gain More Weight than the Food You Eat

I was wondering if it's possible gain more weight than the mass of the food you eat. At a first look, this is impossible because of the principle of mass conservation, but are there other things to ...
5
votes
1answer
117 views

Mites on ginger root

I was just looking at some mouldy ginger found in the fridge under the microscope and was horrified/delighted to find (what looked to be) mites growing in it. I have searched the web and can only find ...
5
votes
1answer
134 views

Fats as energy source

As we know that the preferred source of energy for our body (source) are carbohydrates but heart muscle is an exception and need some explanation for this exception, that why the preferred source of ...
5
votes
2answers
250 views

How do large herbivores get enough protein?

The food they eat seem extremely low on protein. Do they need less protein per mass unit than carnivores? Most of them grow quite a lot in the first year, is most of that from the mothers milk?
5
votes
1answer
61 views

Vitamin and mineral contents of common fruits

I'm looking for nutritional data, mostly vitamin and mineral contents of common fruits, such as apples, bananas, oranges, kiwis etc. Are there scientific (published and peer-reviewed) sources that ...
5
votes
1answer
170 views

functional hypocholesterolemia due to very high HDL or low LDL?

Nutritional and medical recommendations about cholesterol seem to focus exclusively on hypercholesterolemia, and as such, they provide only a maximum desirable level for LDL and a minimum for HDL. ...
5
votes
0answers
69 views

How does a garlic clove thrive inside a closed refrigerator?

A garlic clove has been growing very well inside a closed refrigerator. It has developed beautiful green stalks, which I think are the equivalent of leafs. Since they are green, I assume they ...
4
votes
1answer
7k views

What does the term 'bioavailability' mean?

From what I've read, Bioavailability is the degree to which food nutrients are available for absorption and utilization in the body. How would you explain this with an example?
4
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1answer
219 views

What are minerals (other than zinc) that the human body cannot store

It is known that zinc is an essential mineral that the body cannot store. What are other minerals, especially metals, that the body cannot store? (other than water-soluble vitamins such as vitamin B ...
4
votes
1answer
24 views

Enzymes and Digestion

If biological enzymes (protease,amylase,lipase etc.) just speed up the reaction (in the digestion process), then what actually digests the food?? (I'm a secondary student)
4
votes
1answer
302 views

Do plants have preference for the form of nitrogen as nutrient?

In the nitrogen cycle (ecology), it is usually described that plants can use nitrogen in the form of ammonium (NH4+) and nitrate (NO3-). Do plants prefer one form of nitrogen over the other?
4
votes
1answer
77 views

Oxidation means inflamation?

All right, I was reading article on nutrition, that focussed on content analysis of pastry-like food product for kids. I have to say that I am not sure this article would pass the imaginary smell ...
4
votes
4answers
304 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
votes
2answers
167 views

Can carnivores survive on a (processed) vegetarian diet? Why or why not?

There are many differences in for example the digestive system between carnivores, herbivores and omnivores. It seems that in certain kinds of species adaptability with respect to diet is possible. ...
4
votes
1answer
2k views

Which are mobile and immobile elements in plants?

I am confused with this element or nutrient classification in the plants, since some authors set elements like $\ce{S}$ and $\ce{Ni}$ as mobile and other as immobile elements (Citation 1, 2, 3, 4, 5). ...
4
votes
1answer
438 views

Is the amount of phosphoric acid added to colas enough to disrupt the function of the kidney over the long term?

Both Coca-Cola and Pepsi add phosphoric acid $H_3PO_4$ to their colas to give them a signature "bite". The kidneys use a phosphoric acid/dihydrogen phosphate/hydrogen phosphate homeostasis as one ...
3
votes
3answers
296 views

What Defines a Food as Edible?

With many foods today containing chemicals, agents and preservatives etc... What biological criteria must a new food and its constituent components satisfy biologically, to be defined as edible? ...
3
votes
1answer
391 views

What is the distinction between the terms detrivores, decomposers, saprotrophs and saprozoic organisms?

All of them feed on dead and decaying matter (detritus). Detrivores and decomposers are distinct, as it says on Wikipedia, in the fact detrivores consume macroscopic clumps of detritus while ...
3
votes
4answers
377 views

Why do the humans become sleepy after meals?

I don't know about all the mankind, but I know enough people, who becomes sleepy after their meals. Also, I'm not sure, what kind of food do they consume, but I personally get sleepy almost from any ...
3
votes
1answer
143 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
votes
2answers
32 views

Is there evidence to suggest that nutrients in vitamin capsules are not as readily absorbed as the same nutrients in whole foods?

I recently fell ill with a cold, and began to take a vitamin C capsule each day to help my immune system. When I noticed no change in my condition, I began to incorporate an abundance of citrus into ...
3
votes
1answer
813 views

From a purely biological perspective, how does an optimal human diet look? [closed]

There is hardly any subject as contested in the media as what humans should eat. Usually, such discussions are devoid of actual scientific reasoning, though they all claim to be backed by scientific ...
3
votes
1answer
60 views

Which part of oranges contain fiber?

I think it's pith, but here (non-english country) many chef suggest orange's vascular veins which look "fibrous" and have similar translated word with "fiber" itself. Please enlighten me which?
3
votes
1answer
31 views

Why is it so hard to find the amount of biotin in food? [closed]

According to the WHO publications biotin is a thing we need. Although its non toxic, so you can't get too much. However, excluding a few (small) lists that deal exclusively with biotin content there ...
3
votes
1answer
86 views

What's the difference between diuretic veggies and alcohol that make the latter bad?

So I'm reading this article to Treat Fluid Retention and it suggests Eat foods with diuretic properties. But also Avoid drinks that will dehydrate the body such as tea, coffee and alcohol. ...
3
votes
1answer
84 views

Chemoautotrophy in large organisms?

The major nutritional mechanisms include chemoautotrophy, heterotrophy (including parasitism and saprotrophy) and photoautotrophy. All of these modes of nutrition developed first in prokaryotic ...
3
votes
0answers
36 views

How to quantify quality of vegetables and fruits?

I am interested in knowing if there have been studies in quantifying the quality of vegetables and fruits. By simple examination, it is possible for us to identify if a particular vegetable is ...
3
votes
0answers
72 views

Why doesn't lard taste good? [closed]

I mean looking from evolutionary perspective sugar tastes sweet and individuals that had this perception ate more sugar and survived and those that didn't perceive sugar as sweet didn't eat it and ...
2
votes
2answers
161 views

Does the human body convert water?

I just read Andy Weir's "The Martian" (which was very good) and one line made me wonder: [...] a human body only borrows water. Is that true? Does all water "that goes in, go out"?
2
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2answers
347 views

How do roots obtain nutrition?

I have a city garden (see picture below) and yesterday I was nurturing it and I pulled up a small plant. I saw its root system and laid it in the sun to dry a bit and then scraped of the rest of the ...
2
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1answer
104 views

Consequence of Plants as Incomplete Protein Source

Some years ago, in a 1000~ level biology course we learned that the DNA essentially encodes formulas for creating proteins from amino acids. While the human body can synthesize many many amino acids, ...