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Is it true? we don't gain weight more than the weight of food we eat?

  1. Aug 29, 2012 #1
    Hello, Chitose here

    Just as the topic said,

    I'm I right? to believe that our body never gain weight more than weight of food we eat (and drink).

    'cause mass won't come from nothing.

    we eat 100g of food, when it came out is less than that, part of it become our body mass (weight, height, etc) even drink also the same.

    I ask because my friend won't believe it.
    She try to diet, she says she eat vegetarian food (such as salad) for less calorie and high fiber, but she eat whole lot of it... and still fat...


    to control our body weight, which one is to considered most? calorie or amount?

    a single cup of instant noodle (High cal, low amount), and bowl of salad (Low cal, high amount) which one gonna make me fat?


    English is not my native language, sorry if I'm wrong in spelling or gamma.
  2. jcsd
  3. Aug 29, 2012 #2


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    Staff: Mentor

    No, it is not correct, the weight of the food you eat is irrelevant, it is how many calories that are in the food that matter.
  4. Aug 29, 2012 #3
    It sounds like your friend knows what she's talking about. The actual amount of energy, measured in calories, in the food is what matters. There are different forms of energy, called carbohydrates (sugars), lipids (fats), and proteins. Proteins aren't anything to worry about when it comes to controlling one's weight. It's sugars and fats that contribute significantly to body weight. Sugars do more to prevent one from burning the stored fats than to actually increase weight. Most of body weight (above normal) is stored fat. So, in short, eat less calories and especially avoid food/drink high in carbs, because the are used before fats stores, and thus slow weight loss.

    The point of fiber is that it's like filler. It has no calories, but it makes you less hungry just by the fact that it's in your stomach.
  5. Aug 30, 2012 #4


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    Staff: Mentor

    While I get what you are saying, you are lucky no physicist have seen it, as that would be a crackpot ban.
  6. Aug 30, 2012 #5
    Haha, how about this? There are several molecules, namely carbohydrates, triglycerides, and proteins, that the body is capable of breaking down to utilize their energy, which is stored in the chemical bonds therein.
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