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Why some people are more prone to weight gain/obesity than others

  1. Jul 6, 2010 #1
    Although there can be several different factors/reasons for this, I think one of the factors has to do with how the body packs fats, extra calories. The ones less prone to weight gain problem have genetically-controlled high ratio of fats per unit volume than that of the less fortunate ones, according to so-called world standards, of course.
  2. jcsd
  3. Jul 6, 2010 #2
    There are a number of contributing factors on the table from the bacterial content of the gut, to issues with satiation. I don't believe that the issue is one dimensional or as simple as you seem to imply.
  4. Jul 6, 2010 #3
    Hi Nismar

    I didn't say it's one-dimensional and a plain issue; I just voiced my opinion about something which I consider contributes to weight gain.

    Best wishes
  5. Jul 6, 2010 #4
    I think genetics definately has the most impact on how much weight we gain. I'm sure there are lots of other smaller factors such as "bacterial content of the gut" but when tit comes to tat genetics is probably most the dominant factor
  6. Jul 7, 2010 #5
    In that case, I think you're right, more than any other cause the way the body manages adipose tissue is probably the single greatest factor.
  7. Jul 7, 2010 #6
    Thank you for the clarification, Nismar. Riddler, my thanks also to you.
  8. Jul 7, 2010 #7


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    One factor, that I don't know whether actually exists, might be the following:

    A reduced efficiency to transform fat in a usable form, so that a greater intake of food is needed in order to gain sufficient nutrition.
    A side-effect would be an accumulation of unused fat, i.e, weight gain.

    Again, this is mere speculation on my part..
  9. Jul 7, 2010 #8
    Hi Arild

    I'm sure that your speculation has some validity. Thanks for sharing it with us.
  10. Jul 7, 2010 #9
    look up the Pima indians. they manage to "transform fat in a usable form" just fine when living a more primitive, less sedentary lifestyle. that is, when "forced" to burn it off.

    for some other people, an increase in calories consumed can result in more activity involuntarily via non-exercise activity thermogenesis (NEAT).
  11. Jul 7, 2010 #10
    It can't be a greater factor than diet.
  12. Jul 7, 2010 #11
    Really? You don't know some skinny people (ectomorphs) who can eat anything and not gain a pound? You don't know people who pack on the pounds with the slightest deviation from a diet?
  13. Jul 7, 2010 #12
    Hi Proton

    What kind of relationship are you trying to suggest between 'Pima' and 'some other people'?

    NEAT increases with overfeeding and decreases with underfeeding. Thus, NEAT could be a critical component in how we maintain our body weight and/or develop obesity or lose weight. The mechanism that regulates NEAT is unknown. However, hypothalamic factors have been identified that specifically and directly increase NEAT in animals. By understanding how NEAT is regulated we may come to appreciate that spontaneous physical activity is not spontaneous at all but carefully programmed.

    Source: http://www.ncbi.nlm.nih.gov/pubmed/12468415
  14. Jul 7, 2010 #13
    Pima, as a group, are quite prone to overeating, obesity, and the diseases that accompany that. within the context of a modern sedentary lifestyle, that is.

    as a group, people other that Pima are somewhat less likely to suffer this fate. this suggests a strong genetic component.

    some of us in the not_Pima group (perhaps even a few Pima) have a fairly strong resistance to becoming obese in the face of the modern lifestyle of caloric excess and sedentary living. NEAT appears to be a big factor here.
  15. Jul 8, 2010 #14
    1. Young people, high metabolism, low musculature, lots of inner-body fat which isn't as visible as the hypodermal one.
    2. Older people, women in particular.

    When speaking of OBESITY as a large phenomenom, I doubt it's genetic mutations that has made a third of Americans obese.
  16. Jul 8, 2010 #15
    Why not? There is also the addictive element of the Dopamine-Reward system, and we know that some are more prone to addiction than others. Metabolism, behavior... I don't claim that nature is the winner, but I don't think you can pin that one for a third of Americans, on nurture.
  17. Jul 9, 2010 #16
    well, at least two things are pretty clear. we eat more calories than we did a few decades ago. and we burn fewer calories via activity of various types. i think we're mostly just victims of our own success. gluttony and sloth have been known problems for ages. it is part of human nature (or dopamine reward systems, if you like). the only difference now, i think, is that the option is much more available. people didn't get fat so much before because their environment did not permit it.
  18. Jul 9, 2010 #17
    Then why are only one third of Americans overweight, and so few Japanese compared to them?
  19. Jul 9, 2010 #18
    because we're not all the same ?
  20. Jul 10, 2010 #19
    ...Which brings me back to genetics.
  21. Jul 10, 2010 #20
    "Super Size" that order! My remote broke and i"ll need those 4000 cals. to change channels..!...:biggrin:
  22. Jul 10, 2010 #21
    to an extent. for many of us, we're adapted to a different environment, and the environment has changed. we weren't so fat before the environmental change, so i think it is fairer to say that a change in environment has made us more obese, not genetics.
  23. Jul 11, 2010 #22
    Proton, I subscribe to what you saying. Genetics do have a role to play and we are all different - some more prone to obesity and some less. We cannot simply accuse genetics of all this. We have started to love and save our calories!
  24. Jul 11, 2010 #23
    I'm the same weight I was at 21 years of age, or at most 5 pounds heavier. I think satiation has something to do with it. If I'm hungry and busy, I can put hunger aside, which is often. At rare times I will wolf down food, and others stare in wonder that I don't gain weight. They don't know that, more often, I'm abstaining from food, and that I find being overstuffed very uncomfortable.

    Point 2: Those of Japanese decent, living in America, can be just as overweight as those of European decent. Is it in parity? I don't know.
  25. Jul 11, 2010 #24
    I'm an ectomorph also. My total weight variance in 28 years has been less than 5 pounds. My eating has ranged from huge to next to nothing, and my exercises has ranged from 8 to 10 hour days of intense labor to an entirely sedentary lifestyle. My muscle tone has varied greatly, yet my weight has stayed the same.
  26. Jul 11, 2010 #25


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    Sounds like my_wan stands for "my weight always normal". :smile:
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