Questions tagged [nutrition]
The study of the appropriate provisions required to sustain life in an organism or the provisions themselves.
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Does food lose some of its mass in form of energy during metabolism?
I had an argument with someone.
I argued that when a cat eats 1 kg of food, the sum of subsequent output (poo + pee + sweat + change of body mass) must be equal to 1 kg.
My opponent argued that the ...
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What is the percentage of food that goes to a lamb fetus?
Does any one know the percentage of food eaten by a pregnant ewe that goes to the lamb fetus?
Specifically how much does the mother take for her body from every one kilo of food
and how much does ...
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How can a drink contain 1.8 kcal energy while 0 g fat/carbs/protein?
How is it possible that the Red Bull Zero contains 0 gramms of fat, carbs and protein, but it still has 1.8 kcal of "energy".
I always thought that the human body can gain energy only from 3 kinds of ...
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Why doesn't the soil get depleted after repeated clearing of vegetation?
In my neighborhood, there is a hillside owned and maintained by the local municipality. The hillside is generally overgrown with vegetation. Work crews clear out the vegetation multiple times ...
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Why do we need to diversify our food sources to live healthy, where other animals live happy on one source?
We read about eating different food to get all vitamins and minerals our body need, and often you find people fail to get the daily amount of a certain thing.
I wonder why we humans need to do this ...
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What are the bare minimum nutrients required to survive as a human?
I am trying to determine the bare minimum nutritional requirements to survive as a human, ignoring energy (caloric) requirements. Another way to ask this question is: What elements can humans not live ...
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What allows grass eaters to digest cellulose?
Scientists are saying that it was a small step for the Panda to move from a meat diet to a grass diet. The article only refers to differences in the Panda's skull, presumably for better chewing.
I've ...
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Why are dietary recommendations for methionine consumption combined with cysteine?
I want to understand the amino acids missing in certain vegetables. I looked up the US recommendations for amino acids
(source: wikipedia).
I don’t understand why they pair
Methionine + Cysteine: 25 ...
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Why is exclusive breastfeeding recommended for 6 months only?
The WHO recommends exclusive breastfeeding for the first 6 months of a child's life.
Review of evidence has shown that, on a population basis, exclusive breastfeeding for 6 months is the optimal ...
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Understanding food composition data from USDA for Vitamin A
When researching the nutritional value of carrots the Vitamin A comes in two measurements as RAE and UI:
https://ndb.nal.usda.gov/ndb/foods/show/11124?n1=%7BQv%3D1%7D&fgcd=&man=&lfacet=&...
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What is the consensus, if it exists, on the (absence of) biological effects of artificial sweeteners?
I tried to Google (and PubMed) the question, but it seems to be fairly polarized debate and there does not seem to be a consensus as to whether sweeteners like asparatme, acesulfame etc. have ...
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How does zoo and laboratory animal feeding work?
What steps are taken to ensure those animals are fed adequately? When dealing with larger populations of animals, how is it ensured that all of those animals received food during a certain time period,...
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How do people measure how many calories or proteins/fats/сarbohydrates are in some food?
How is the composition (in fats, proteins or carbohydrates) of a certain food estimated and how is the amount of calories provided by the food calculated?
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Why are plants unable to take up Phosphorus directly in their organic form like Phytic Acid?
I am researching acquisition strategies of phosphorus by decidious trees. I am reading a lot that plants take up nutrients as their inorganic form. In the case of P according to literature this is ...
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How does a glucose molecule enter the cell from blood vessel?
The transporters in the plasma membrane of the cells promote the entry of glucose molecules from the extracellular matrix to the cytosol of the cell. Could someone explain how does the nutrient ...
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Can supplements affect DNA? (Could 10,000% Methylcobalamin affect MTHFR genotype)
Originally titled "Could B12 supplementation affect dna test results for B12 need?" - B12 just seems like a good example question to frame the more general question of "Can supplements affect DNA?"
I ...
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Why does protein have 4 calories per gram?
As I understand it, protien that isn't used for building and repairing the body is inefficiently converted into glucose in the liver (at a rate of roughly 3 grams of protein per gram of glucose ...
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Glycogen replenishment after exercise
In the body, the liver holds between 90-110 grams of glycogen in storage, while skeletal muscle storage makes up another 400 grams.
If a person exercises and depletes both stores, when a carbohydrate ...
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How is the urea cycle regulated with respect to protein deficit?
Proteins cannot be stored in the body. Excess proteins from the diet are deaminated in the urea cycle that takes place in the liver. The liver is the first contact since these amino acids are ...
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Why does drinking milk lead to increased fractures?
Milk has always been associated with strong bones due to the high amount of protein and calcium in it. Yet reading it up on wikipedia,
A study published in The BMJ that followed more than 45,000 ...
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Is this answer about the limiting factor correct?
The graph shows the result of adding both phosphorus and nitrogen to different algae populations. I have a hard time figuring out why the correct answer is C, I thought that groups 4 and 5 would have ...
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Where different types of proteins can be found in food?
According to https://www.youtube.com/watch?v=KSKPgaSGSYA (created by one of the largest supermarket chains in the UK), different proteins have different roles in human body:
(Group 1) They’re like ...
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How big is a baby's stomach?
There is a lot of contradictory information on baby feeding volumes on the internet. A common claim is that a baby's stomach is the size of a hazelnut or small marble, with a volume of 5-7 ml. But ...
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sweet receptor's affect on insulin release
So I understand the basics of how the body releases insulin to keep blood glucose levels in check and (loosely) that higher insulin levels can lead to more (or at a faster rate) glucose being stored ...
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Is there a standard way of measuring culture nutrient levels in real time?
I am working on optimizing growth rates for a culture, and one thing I'm trying to monitor is nutrient consumption rates to pinpoint any bottlenecks, i.e. the culture goes through all the calcium in a ...
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Is biotin a hapten? If so, how does it work as a hapten in the human body?
https://en.wikipedia.org/wiki/Hapten
Hapten's aren't synonymous with allergens. It is defined as a foreign molecule that can bind to an antibody but does not evoke an immune response unless combined ...
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Ingestion of cellulose digesting prokaryotes? [duplicate]
If humans digest cellulose digesting prokaryotes, can we start digesting cellulose like cows?
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Carbohydrate diet and dental health
I read that human started carbohydrates rich diet after adopting agriculture before that meat was main energy source which has comparatively less carbohydrate. High carbohydrate started destroying ...
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Where do kombucha SCOBYs get nitrogen?
Kombucha can be brewed even with tiny amounts of inocculate, such as the little bit of sediment at the bottom of store-bought kombuchas. Over 1-2 weeks, this can grow into an inch thick film covering ...
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Why does enteral carbohydrate yield higher energy than parenteral?
The following is written in a well-known textbook of surgery:
Each gram of enteric carbohydrate provides 4.0 kilocalories (kcal) of
energy. Parenterally administered carbohydrates (eg, ...
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Are peanut proteins similar to chicken meat proteins?
I'm studying amino acids content in vegetable food. I was looking at peanut protein and noticed its similarity with chicken meat, as you can see in the table below (quantities are measured in grams). ...
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Why do plants produce and store both amylose and amylopectin?
Since both forms of starch has its primary purpose of storing glucose and hence releasing energy, why are there 2 variations of this sugar? Is it possible for an organism to contain/depend only on 1 ...
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What nutrition do flies find in feces?
How are flies able to extract nutrition in feces when the originating animal wasn't able to? What makes flies more capable?
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What is the most readily usable form of nutrients/energy source for heterotrophic microorganism in general?
Consider a nutritious mixture containing abundant soluble sugars, soluble lipids and soluble protein etc. Would heterotrophic microbes preferentially use sugars first > lipids > proteins > insoluble ...
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Plant vs animal protein digestibility?
The protein scoring methodologies ( https://en.wikipedia.org/wiki/Protein_Digestibility_Corrected_Amino_Acid_Score) rate plant proteins of a lower quality than animal proteins. Now I can understand ...
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How do we know we have to use the mouth for eating and drinking?
I have a question that I am very curious to: how do we know we have to use the mouth for eating and drinking? Because we have multiple openings where, if we didn't know better, could put food and ...
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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. ...
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Raw food diet digestion
I haven't really paid attention to the raw food diet and the claims of its supporters until now. A passage from this website says:
The basic premise behind preparing raw food is not to cook food ...
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How much time can a human survive only drinking water and eating sugar? [closed]
If a person only drinks water and eats glucose, how long could they survive before getting any symptoms? When would the damage become irreversible? When would that person die from lack of minerals, ...
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Human can't digest cellulose.....but the length of small intestine is approximately same in humans and herbivores [duplicate]
My question is why herbivores are able to digest cellulose and why can't we??
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How a vegan can consume all the needed varied proteins / amino acids?
I would like to ask if there are some proteins that the human body needs and can being endowed only from meat?
According this:
Other protein sources, such as fruits, vegetables, grains, nuts and
...
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Organ of ingestion in lice [closed]
I want to know that what the name of the organ used by lice for ingestion is? (also please explain if possible). In my research, I got this wiki page that didn't help me out. Then I found this link ...
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What does a typical, perfectly healthy vaccinium corymbosum (highbush blueberry) leaf look like?
What does a typical, perfectly healthy vaccinium corymbosum (highbush blueberry) leaf look like?
Colour (darkness of green, redness)
Waxiness
Veins
I'm guessing that soil ph, nutrients, and other ...
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Watering plants with soaked forest soil [closed]
I am thinking of mixing forest soil with water and water plants with that.
I was hoping that nutrients from soil would get released into the water, so in effect, fertilize the soil.
I am not sure if ...
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Does hunger necessarily mean that we should eat?
People feel hunger sooner after they eat food that consists mostly of carbohydrates. For example, if someone eats a good portion of rice then most likely they will be hungry after a couple of hours. ...
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Need / consumption of magnesium
Does doing sports makes a human require more magnesium and – if any – how strong is this effect?
Do athletes take magnesium supplements (e.g. pills of magnesium carbonate) because they build muscles ...
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Is human blood useful as food?
Lacking other resources, could a healthy adult slit his wrist to feed a starving child with his blood? Would it be nutritional and would a starving dehydrated child eat it?
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What would happen if all magnesium was removed from a person's body? [closed]
Magnesium is essential to bodily functions. It enables ATP from which most energy is produced in cells. It regulates over 300 biochemical reactions in the body. It is important to the transfer of ...
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Why aren't nucleic acids on Nutrition labels? [closed]
All the other macromolecules are listed on the Nutrition labels and nucleic acids do have some caloric value, why aren't they on the nutrition facts?
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Protein content in sprouted beans
I have checked on Wikipedia which says that sprouted mung beans has way less protein than normal one, while on web you will find articles saying sprouted beans are best, which is true, how do I eat ...