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Body can make anything such as proteins, fats etc from simple sugars

  1. Aug 18, 2010 #1
    I'm not a science student. So, please keep your reply simple and straightforward. Thank you.

    Human body needs water, carbohydrates, proteins, fats, and vitamins in order to function properly and survive. Please correct me if I'm wrong. I once read that apart from some essential amino acids, essential fatty acids, water and vitamins, a human body can almost make anything such as proteins and fats etc from simple sugars like glucose. But is the rate of production of complex molecules from glucose so high that it can meet the daily needs of a human body? Please let me know.
  2. jcsd
  3. Aug 18, 2010 #2
    the need for glucose and amino acid stores in our body is just one example of highly different nutritive pathways that exist. there are several various nutrients needed to sustain life in addition to sugars that cannot be synthesized from sugars. many vitamins for example must be directly ingested and can't be produced internally. vitamin A is one. Vit A is the most lacking in 3rd world diets and the statistics show its the #1 deficient nutrient in the world's hunger spots, someone google check me this is ten year old a and p recollection. other metals such as selenium, salt, calcium etc are also required and must be ingested, cannot be made from sugars, they are their own elements.
    in no way can proteins be made from sugars they must be ingested, broken down to amino acids, and then sequestered by cells as needed to produce the body proteins directed in given cells.

    fats and sugars are interchangeable depending on the species at hand and the body runs head-spinning conversions between the two, in the presence of oxygen or not etc (biochem majors speak up)

    Off hand, without googling anything, Im guessing there are probably a hundred individual nutrients required to sustain life in humans, sugars are just a small percentage of it.
  4. Aug 18, 2010 #3


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    If you're trying to indirectly ask how much you can restrict your diet, you can eat only essential amino acids, essential fatty acids, and inorganic minerals. The Chukchi, for instance, have existed for centuries at least eating only reindeer for most of the year. So your analysis is a little backward. Not only can you not survive off of carbohydrate alone, but it's actually the only macronutrient you don't actually need to ingest at all.
  5. Aug 18, 2010 #4
    Hi LYN

    Yes, this is what I was trying to ask. If I eat only essential amino acids, fatty acids, and inorganic mineral, then I believe my body will start cannibalizing itself for other things. First it would eat out stored fats, then bones etc. Do you really think one can survive on water, amino acids, fatty acids, and inorganic minerals? Perhaps, one could but only for a certain period of time. Please guide me.
  6. Aug 19, 2010 #5
    A standard human lifestyle requires between 1000 and 2000 calories of energy daily(sugar, protein, or fat), chemicals that it has lost the ability through evloution to produce like vitamins(named because they are vital), essential amino acids, essential fatty acids, and inorganic minerals(metals for enzyme activity and others for ion exchanges). Vitamin D is an exception as you can make your own if you get enough sun exposure. Every other item your body needs can be made on it own. Exercise might also be vital to ensure the quality of life, however you didnt quite ask that.
  7. Aug 19, 2010 #6
    The biggest deals are: essential aminos (you WILL die without any one of them eventually) and vitamins/minerals. Eat pure sugar and your organs and muscles will be pudding before you die; Scurvy is just one mild example. You can live on blubber and seal meat, with the occasional bit of partially digested greens from the gut of said seal. You cannot live on toast.
  8. Aug 19, 2010 #7
    what an interesting thread Im curious as to where OP was coming from with the first post. is it a school question, or a diet in consideration...
  9. Aug 19, 2010 #8


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    The problem with limiting your diet to "essentials" only, is it doesn't provide your body with enough "quick burn" energy needed to sustain a healthy and active lifestyle. I suppose if you wanted to sit on the couch all day and take up lethargy as a pastime, then that may mean your nutritional demands, the average person however, needs to ingest expendable fuels need to keep up the supply of ATP you tear through each day.
  10. Aug 20, 2010 #9
    nice call quality of life wasn't even considered so far.

    and stomach pangs

    at least we arrived at the fact glucose stores are depleted by different mechanisms than being broken down to make proteins, lets rattle off some ways glucose stores are used up in the body to show the OP how they are being depleted and what its used for when changing states:

    -glycogen stores in muscle
    -metabolic pathways for respiration
    -excretion in urine? guess
    -exclusive fuel for brain cells

    thats all I can think of ya'll add some more
  11. Aug 20, 2010 #10
    Yeah i think some small ammount of sugar is needed in some form. Even if its only 1/100 of total calories. The liver would go into hysterics trying to provide all the needed sugar. Probably even fatal. And you cant say its just making enough for the brain to survive with because there probably isnt a communication system to tell the body not to grab it because its all for the brain.
  12. Aug 20, 2010 #11
    Thanks a lot, everyone, for your replies and guidance.

    I was speaking about a couch potato who . If he takes water, essential amino acids, fatty acids, vitamins, minerals, and glucose, would he be able to enjoy his life as far as his couch domain is concerned? In other words, is this true that the body can sythesize materials such as proteins and fats from glucose?
  13. Aug 21, 2010 #12


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    Its not that straightforward. The body can synthesize many nutrients from precursors, whether or not the body can do that efficiently enough to maintain "life" is another matter all together.

    Proteins are made from translation of RNA transcripts, by joining amino acids together. Making some of those non-essential amino acids, like glycine or glutamic acid means taking away substrate from other cellular metabolism processes like glycolysis or the citric acid cycle.

    While those wouldn't be considered "essential amino acids", I think it would be pretty hard to meet your nutritional demand for non-essentials by eating sugars.

    Also, many other substances in the body are considered "non-essential" because the body's ability to make them, but again we run into efficiency problems.

    In some people, despite their amount of exercise and what they eat, they get high levels of cholesterol produced by the liver. On the flip side, some people's liver doesn't make enough cholesterol (an important precursor to all kinds of hormones and something integral to cell membranes), which when lacking in their diets will result in a deficiency and a disease state.

    Let's also not forget that your body goes through cycles of higher and lower nutrient demands, such as when you get sick, are growing or healing (etc).

    A nutritionally minimal diet would really depend on the person, their health and their lifestyle/life cycle. Its not something that would be a healthy choice to try.
  14. Aug 21, 2010 #13
    A person could SURVIVE in this state. But a disease state would follow. We just didnt evolve to be so autotrophic(self sustaining). It would be unethical to test a human to this level. Also going to the restroom without dietary fiber would be miserable. If this stiuation happened to a friend or family member the best thing to do would involve a social worker, a psychiatrist, and an electric cattle prod.

    (JK about the cattle prod)
  15. Aug 21, 2010 #14
    I think we're all agreed: DO NOT TRY THIS AT HOME. :rofl:
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