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Food cravings.

  1. Aug 19, 2010 #1
    This probably falls under some "wholistic approach" myth towards dieting.

    This is a very tricky idea but it's one I hear a lot from various people in my life. I have NEVER once seen an article addressing this assumption about hunger and it might simply be an urban legend/hypothesis or folklore. People that I meet make this assumption all the time. There is no link or source or paper that I know of regarding this. It is urban folklore as far as I can tell.


    Can the human body cause a sensation of hunger for the exact nutrients it needs (to be healthy) at a specific time?

    A craving for protein, carbs, salts, fats and then into specific vitamins and proteins etc because that is the exact requirement at that specific moment?

    If a person is hungry and craves fish (seemingly at random to the person) is there any evidence that this person requires any nutrient that fish provides at that specific time?


    Another example. Oysters are high in zinc..

    Is there any evidence that a person craving oysters is lacking in zinc?

    That is just an example.
    It would seem like a very tough phenom. to study.


    I am not talking about a general sense of craving food when you are simply hungry (I can understand that.) I mean hungry for a very specific food that has a very specific nutrient that you just so happen to be depleted in.


    Many people I speak to assume this to be true but I am not so certain it is true. I get ice cream cravings, chocolate cravings but mostly cravings for salty food : none of it is a healthy craving. Although occasionally (rarely) I will desire a food like broccoli and mention it to my wife and she will say "You probably need iron."
     
    Last edited: Aug 19, 2010
  2. jcsd
  3. Aug 19, 2010 #2
    People definitely get cravings for specific things that they require nutrients from. Pregnant women are the best example, as are people starving (e.g. survivors on life-rafts etc).
    From experience, its pretty clear that most cravings (e.g. chocolate) are something else.
     
  4. Aug 19, 2010 #3
  5. Aug 19, 2010 #4

    Ivan Seeking

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    We need a definitive link.
     
  6. Aug 20, 2010 #5

    Chronos

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  7. Sep 4, 2010 #6
    " In fact, scientists have largely debunked the theory that food cravings are our bodies' ways of nagging us that we need a specific type of nutrient "
    http://www.howstuffworks.com/framed....com/article.cfm?id=are-food-cravings-the-bod

    That quote was in that clip above with a link and yet when I read the link it was not confirmed.


    They did add this at the end though.

    ""Cravings" undoubtedly represent a true bio-psycho-social paradigm in which sociocultural factors, stressful environments and hormonal fluctuation participate in a complex drama performed on a neurological stage and the result has varied--and as yet incompletely understood--implications for nutrition and health. "

    I read that as : Inconclusive.


    Look I would love it if we could tell what our bodies needed at specific times by understanding our own hunger better: the correct amounts of vitamins, the right amino acids, the right combinations of fats, carbs, proteins at specific times when we require them only. I would love to be full when I have satiated myself with the exact correct amount and specific types of food by simply feeling it. I doubt that it could ever work like that for anyone though.

    Also what about that sensation when you feel like you've gone past hunger and are no longer hungry? Is there even a name for that? I doubt it is a healthy state to be in, yet I think everyone has experienced it. The cravings are gone at that point yet we probably do need food. I bring that up because in that case the cravings are incorrect. Perhaps that is experiencing the sensation of catabolism? If I knew a name for that after hunger feeling I could look it up.
     
    Last edited: Sep 4, 2010
  8. Sep 9, 2010 #7

    FlexGunship

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    Actually, if you take a survival class, they tell you to wait for this feeling before hunting or foraging. The feeling of hunger is largely the feeling of your stomach emptying not actually being empty (which is why your stomach growls when you feel hungry). The feeling of an empty stomach is the feeling you describe. We are such a privileged society/species now, that we equate an emptying stomach with an empty stomach.

    Most people have not actually felt primal hunger. Don't eat for 36 hours and see how you feel. That's hunger. It comes with a headache and sometimes cramps. If you go for about three days (maybe a bit longer) you will feel muscle pain as your body begins the slow process of ramping up to eat itself. Full metabolism of muscle begins at between 5 to 7 days using ketones created from stored fat. During this time you can no longer regulate your blood sugar levels and will begin hallucinating.
     
  9. Sep 10, 2010 #8
    To piggyback on FlexGunship's post, we do eat in survival school, but not much. About a third of an onion, a third of a potato, an ounce or two of meat, and some salt each day.

    Here's what happens:

    Day 1: You're hungry.

    Day 2: You're hungry, have a headache, and are tired.

    Day 3: You're hungry, are tired, and a bit sore, but begin to slip into "hunter mode." You gather local food sources, including berries, leaves, whatever is edible.

    Day 4: You're hungry, alert, and light on your feet.

    Day 5: You're scanning the woods for anything and everything you might catch by any primative means, from squirrel to rabbit to deer. If you're lucky/skilled enough to catch something, you share it with the group that night and are deemed a hero.

    It's usually by day 4 or 5 you're fed a decent, well-rounded meal. The instructors don't want people hallucinating during training.
     
  10. Sep 10, 2010 #9
    Absolutely, though it's not terribly specific. For example, I know if I stop taking my GNC vitamins, my food cravings change considerably, and I often wind up chowing down on some strange things (like sardines) when I should be eating better. Whether that's because I'm missing vit A or vit D is unknown. Taking vitamins takes care of my vitamin and minerals cravings, so at that point it's merely for water, salt, carbs, protein, and fats.

    Again, I don't think the cravings are quite that specific. But the body knows a good bit better than we think it does.

    Case in point: About 2/3 of the way through his summer visitation with me, I caught my son squirting pickle relish into his mouth. After chiding him for the breach in decorum, I realized he'd known it was there and had access to it for 5 weeks, so why now? "Son, when's the last time you took a chewable vitamin?" "I don't, Dad. I'm out." "Oh? How long have you been out?" "About five or six days."

    I think you're right. I think one way to do it would be to allow people to eat from a large smorgesbord, keeping track of everything they eat and how much. The key would be to vary their intake of various combinations of nutrients by means of a "vitamin pill" that's tailored to leave out some key ones here and there.

    By knowing what's in the vitamin pill for that week (or month), and monitoring their eating habits, I think there's be some useful data, there.

    And I know just where you can obtain such subjects: Soldiers in Iraq and Afghanistan. That's all the dining halls are: smorgesbords. Particularly in Talil, Iraq.
     
  11. Sep 11, 2010 #10

    loseyourname

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    Well, it's obvious that doesn't always work. Frontiersmen back in the day frequently died from inadequate fat intake due to the overly lean game meats they were eating, yet died without ever feeling hungry or craving fat.

    The hungry headache feeling followed by loss of hunger is called ketosis and doesn't necessarily have anything to do with actual hunger. You can induce the same feeling by eating an extremely low carbohydrate or even no carbohydrate diet while maintaining a very high caloric intake, even in excess of weight maintenance. The feeling is just your body adapting to fat metabolism, which it has to do whether the fat is your own body fat or fat you're eating.
     
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