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Food, Calories, Weight, Somebody tell me whats going on!

  1. 1 pound or less

    7 vote(s)
    100.0%
  2. More than 1 pound

    0 vote(s)
    0.0%
  3. I dont know

    0 vote(s)
    0.0%
  1. Jul 22, 2006 #1
    Tonight my father and I got into a debate over the weight of food ingested and its effect on the weight of the body.

    4,086 calories is needed to deposit or burn 1 lb of fat

    1,000 grams equals 2.2046 lb


    1 gram of fat is 9 calories
    1 gram of sugar is 4 calories


    1,000 grams of fat is 9,000 calories so that is 2.20 lb
    1,000 grams of sugar is 4,000 calories so that is 0.97 lb

    My argument is that if you eat one pound of any food, the most weight you can gain is 1 pound. Is there any truth to this? My father believes that the energy (calories) can increase the amount of weight, more than the weight of the food.
     
  2. jcsd
  3. Jul 22, 2006 #2

    Pengwuino

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    What exactly does your father think is burnt when you eat food if it isn't the food itself? You're not eating something called a "calorie", you're eating food which can be a form of chemical energy. That energy is measured in calories.
     
  4. Jul 23, 2006 #3

    Gokul43201

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    Lots. It follows directly from the law of conservation of mass.

    That is completely lacking in scientific rigor and hence makes for a worthless argument. You can say this to him in gentler terms, if you wish. But he's wrong.

    PS: In food, I also include water.
     
    Last edited: Jul 23, 2006
  5. Jul 24, 2006 #4
    if it wasnt for inorganic chemistry..... im wondering if there's research being done knowing that about the mass of food.
     
  6. Jul 24, 2006 #5

    selfAdjoint

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    You can't gain any more in any one day than the weight of the food you ate and fluids you drank. In fact if your elimination processes are working properly, you will gain strictly less.

    BUT if that food or those fluids were high in fats you'll gain more than if they weren't; your body will metabolize the fats readiy and store part of the resullt as fat in your body. And even if not fat, if the food or drink was high in calories, your body will have to burn less of the fat it has to satisfiy its energy requirements, so ON BALANCE (mass ingested minus mass egested) you will see a gain in weight, especially if you do this day after day.
     
  7. Jul 26, 2006 #6

    ShawnD

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    Your dad might be thinking of some kind of sponge efffect. Suppose you ate a 10g sponge and it could hold 5g of water. You'll gain 15g even though the sponge itself is only 10g. You wouldn't count the water against your diet because it's just water :wink:

    Think of it like a hydration (or is it dehydration?) reaction. Say you start with something like CH3-O-CH3. Add a water to that and you get CH3-OH + CH3-OH. It's retaining the water, like a sponge!

    Seems a bit unlikely, but I'm not a dietician.
     
  8. Jul 26, 2006 #7

    selfAdjoint

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    The main thing in food that can make you retain water is salt. So if you eat a pound of salty food, the most you can gain from the food is one pound, but you will also be drinking fluids during the day, and the salt can mean that less of that is excreted than if you had eaten salt-free food instead, so you wind up gaining more than a pound.
     
  9. Jul 27, 2006 #8

    ShawnD

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    I did not know that. Does this mean fat people can avoid that temperary "water weight" by reducing salt intake while dieting?
     
  10. Jul 27, 2006 #9

    DaveC426913

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    Yes.

    You know all those weight programs that promise you'll lose 10 lbs. in a week? That's all water. They mostly use diuretics and reduce salt intake.
     
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