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

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49
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11answers
11k views

Can humans survive without consuming life? [closed]

Some people say that it's awful that humans eat animals. They feel that it's barbaric, because you're killing life and then on top of that, you're eating it, and that you should eat vegetation ...
14
votes
2answers
168 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 ...
11
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4answers
1k 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) -- ...
10
votes
2answers
93 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 ...
8
votes
2answers
2k 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, ...
8
votes
1answer
13k 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 ...
7
votes
2answers
76 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
votes
2answers
191 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
votes
2answers
157 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
101 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
votes
2answers
172 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 ...
6
votes
0answers
49 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 ...
5
votes
2answers
255 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 ...
5
votes
1answer
58 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
148 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. ...
4
votes
1answer
170 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 conversation of matter, but are there other things to take into ...
4
votes
1answer
192 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
62 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
54 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
1answer
48 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 ...
4
votes
1answer
53 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 ...
4
votes
1answer
291 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 ...
4
votes
0answers
23 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 ...
3
votes
3answers
206 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
5k 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?
3
votes
4answers
214 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
122 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
1answer
297 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
3answers
155 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?
3
votes
1answer
36 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
80 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
79 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 ...
2
votes
1answer
735 views

How do nutrients get to the cells they need to get to?

I understand the basics of digestion. I know that nutrients get absorbed by the microvilli, enter the bloodstream and travel to the liver but after all that, what is the biological mechanism that ...
2
votes
1answer
17 views

Is it possible to accurately measure micronutrient levels with the blood volume from a Dermal / Capillary puncture?

I have not been able to find much information beyond what tests are normally done with Capillary puncture sampling, as opposed to what tests are possible. Could we test for a single micronutrient, or ...
2
votes
1answer
72 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 ...
2
votes
1answer
468 views

Can animals use the nitrogen in chitin to build proteins?

Fungi and insects contain chitin, which is about 6% nitrogen. Can an animal - like me - make use of this as a nitrogen source to build proteins? Are there any animals that can do this? Are there ...
2
votes
1answer
28 views

Can plants directly use sulfuric acid?

In the explanation of the sulfur cycle, it is often said that sulfur moves from the atmosphere to the ground by acid rain in the form of sulfuric acid. Can plants directly use sulfuric acid to ...
2
votes
1answer
54 views

How do C. elegans manage nutrition?

If there is ample amount of food, do C. elegans worms know when to stop eating or do they store extra energy? Could they put this extra energy to use by moving faster or putting more eggs?
2
votes
1answer
63 views

Leaves not liked by herbivores

I at times have many goats grazing in our locality. Recently a few cows were seen too. I just offered one of the cows a few leaves from Jasminum sambac plant growing in our garden. The cow smelled and ...
2
votes
1answer
32 views

Metabolism of different saccharides

Learning about carbohydrates, I wonder what the differences there are in terms of metabolism, and overall health between the different types of saccharides. In other words, does the body use ...
2
votes
1answer
39 views

What is the common diet of food-related IBS patients? Besides most patients being lactose intolerant, what other intolerances do they face?

I am currently writing a paper on irritable bowel syndrome, and I was wondering what the common diet of a patient with food-related IBS consists of. I've already begun discussing the pathogenesis of ...
2
votes
0answers
44 views

Zinc and brewer's yeast

I'm hoping for some information relating to yeast nutrition (specifically Saccharomyces cerevisea) in beer fermentation. Zinc is well-known to be necessary for yeast cultures to perform successful ...
1
vote
2answers
403 views

Organisms that contain rare chemical elements

By accident, I found a slide from a Polish chemical presentation, that talks about a small group of biological organisms which contain chemical elements not found in the human body, like: B (boron), ...
1
vote
2answers
37 views

How do the 'energy making' processes in the body differ for fat calories, protein calories, and carb calories? [closed]

How does the body make energy from each of the macronutrients? Is there a difference in the efficiency of the distinct processes and would the least efficient process be 'better' for weight loss?
1
vote
1answer
59 views

Is it easier to burn a calorie of fat or a calorie of a carbohydrate?

Say someone eats 100 calories of chocolate vs. 100 calories of carrots. Something tells me that eating the chocolate will lead to you generating more fat. Will it? Is it harder to burn the calories ...
1
vote
1answer
281 views

Human Body “Fat” Equilibrium

Here's my theory: If you consume x calories each day with y amount of caloric expenditure each day you gain zero weight, regardless of x and y being out of balance. If you then mechanically ...
1
vote
3answers
42 views

What are some places where biofilms could develop? [closed]

I'm trying to think of places where a biofilm could develop other than on medical equipment or food processing equipment such as stainless steel mechanized blades or knives. I'm thinking more along ...
1
vote
1answer
36 views

Is the sense for salt depending on the electrolyte level in our body?

I often noticed, after (heavy) physical activity like cycling, running, swimming or working an isotonic drink (to recover the electrolyte level) tastes less "salty" compared to when drinking it before ...
1
vote
1answer
68 views

Do chickens always lay eggs?

http://de.wikipedia.org/wiki/Hühnerei says it takes up to 24 h for a chicken to produce an egg. Is that dependent on the chickens nutrition, i.e., if it does not get enough food or the wrong kind, ...
1
vote
1answer
263 views

What are the pros and cons of eating earth (soil)?

I wonder if there are any benefits to eat earth. What I mean by earth is the topsoil that is sometimes on vegetable (I eat organic vegetables and some of them like spinach are full of topsoil). I ...