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Are Raw Fruits And Vegetables Fattening?

  1. Jun 14, 2013 #1
    Can a person become obese, from eating too many raw apples, or too much raw kale?
  2. jcsd
  3. Jun 14, 2013 #2


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    Staff: Mentor

    Yes, you would have to consume more in calories than you burn, but anything that exceeds that threshold will cause you to gain weight.
  4. Jun 14, 2013 #3
    So you believe a person can become morbidly obese, if they eat too much kale?
  5. Jun 14, 2013 #4


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    They'd probably get sick first, but yes if they could manage to keep it down. This is not different from someone losing weight eating battered chicken fried bacon and ice cream all day. It's calories the body is able to use and/or store versus calories burned.


    But there's no point to this discussion if it's not nutritionally balanced.
  6. Jul 4, 2013 #5
    Just as you posted earlier, it is all about calories in verses calories expended.

    Herbivores are walking proof that weight gain & fat can be put on just by eating plants alone. Most leafy plant matter is relatively low calorie with the bulk of its caloric potential stored as cellulose. Cellulose is tough and hard to digest, but as a herbivore knows, if you consume enough then you can get by on the plant matter alone. Many herbivores spend the bulk of their waking hours eating (grass, etc) as a result.

    Plant wise, fruits and berries contain a high caloric concentration of fructose and it is very easily converted to glucose during digestion. This is why animals are drawn to fruiting trees and plants... easier calories to get than the same amount obtained from digesting pounds and pounds of grass.
  7. Jul 5, 2013 #6


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    An apple a day keeps the doctor away

    I long ago read that apples, an addiction of mine, were the only food with negative energy content - taking more energy to digest than you got out of them.

    But more recently I read that this is no longer true as they have now been bred by the superficial consumer society to have more sugar content.

    But maybe they are still better than other fruit at least?

    It is quite a practical matter - I think we should be told, and perhaps someone here can tell us.
  8. Jul 5, 2013 #7

    jim mcnamara

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    I do not know where the apple information came from. Do you have a citation? It would help a lot.


    Shows the kcal content of apples. This is a discussion of the same claim for celery from Snopes.com

    Note that the same volume of celery has way fewer calories than does apple. If your statement about the caloric change in apples is verifiable, then we can look at it.

    Just to note - you are really talking about the metabolic cost (net energy harvest== calories in food - calories to digest) of some foods that are very hard to digest -- are mostly cellulose for example. Humans also can not digest chitin very well. Cooking affects digestibility of apples and celery. And per E O Wilson: humans evolved to eat cooked food, not raw.
  9. Jul 5, 2013 #8


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    There are no foods that burn more energy than the calories they supply, it's a myth. Found that out last year when I did some research. This article explains it.

  10. Jul 5, 2013 #9
    It's called negative calorie food:
    The idea is that your body burns more calories to digest the food than you extract from the food itself.

    The whole calorie labeling of food is really ridiculous and misleading. These numbers are obtained by burning individual ingredients (fat, sugar) and measuring how much heat is released. Of course sugar and fat have a lot of calories, they burn very well. That doesn't say too much about how much of that energy is being absorbed by my body. Like Jim said, cooking affects digestibility, which is not taken into account.
  11. Jul 5, 2013 #10
    Thanks Evo, you were just ahead of me.
  12. Jul 5, 2013 #11


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    What about drinking cold water? It is, in principle, negative calorie (water provides no caloric value, and it takes energy to bring the water to thermal equilibrium with your body). Of course, the amount of energy used to heat the water is basically negligible.
  13. Jul 5, 2013 #12
    The [STRIKE]Hitchhikers Guide[/STRIKE] wiki link has this to say about drinking cold water:

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