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Intermittent fasting Watch

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    (Original post by Hypocrism)
    What? The stresses or pressures are the factors that determine which mutations propagate, and which are inherited by mere chance alone. A removal of a stress (here, lack of food) doesn't cause the body to rapidly adapt to the new situation of ease, this is why it's reasonable to assume that a cave man diet is healthy, possibly healthier in some ways than modern styles of eating.

    Also, we have only had relatively plentiful food for maybe 10,000 years at best. That's not enough time for these hypothesised mutations you are suggesting to develop (because they would be numerous) and propagate through the human population. Perhaps it's in progress, but I doubt it since as I said, adapting to survive (ie avoid death) due to a stress is far faster evolutionarily (can be in very short time periods) than just adapting to survive slightly better after removal of a stress, because the former is just a far larger evolutionary pressure. This is especially true when you consider that we are talking of a very small reproductive advantage-most deaths until recently were not due to eating in the wrong pattern, they would be due to disease or predation or starvation. Any reproduction would be done at ages affected minimally or not at all by the new patten. So the idea that we have adapted to a slightly better eating pattern is frankly ridiculous.

    Now like I say, I don't think IF is more healthy than modern timing of eating. I think it's really a non-issue, we are equipped with physiological mechanisms to cope with regular food meals and scarce food meals. But the logic behind assuming it has benefits for certain physiological processes is sound.


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    No, the stresses and pressure don't drive the mutation. The mutations are seemingly completely random, it's the stresses and pressure that drive mutations onto the next generation i.e. a random mutation that mutates in a group that survives these pressures. It may seem like our environment causes the mutations but it's not, we are the way we are today because these mutations survived and thus drove the evolutionary process not, the evolutionary process drove us to mutate to the way we are today. We actually don't know what drive mutations, hence why evolution (as a whole) is still regarded as a theory and not a fact (or I suppose you can call it a law). We know evolution happens, but we don't know what are the mechanisms that cause change. Certainly it's never been proven that evolution happens because of the stresses of the environment.

    Infact the saying "survival of the fittest" comes from this, as it is the ones that survive that pass on thier traits to their offspring and thus shape the species. Like I said it's death in numbers that made us what we are today, it was those random mutation that were "lucky" enough to develope in the generations that happened to survive. It may well be that many mutations helped us survive, hence why europeans are better adapted to colder climates. But these mutations or adaptations weren't caused by the stresses that were killing us. If that were the case and it was our changing environment or the stresses of the environment that caused evolutionary mutations then today you could arguing the evolutionary process is starting to stop because we have less pressures in our environment meaning less need to adapt. However we know that evolution is still happening like it always has thus it can't be our harsh environment that causes mutations.

    Although now that you memtion it's only been 10,000 years since a change in diet thus perhaps not enough time for us to have changed that much does make sense. However I'm still skeptical of the whole "it was good for the cavemen" argument.

    Yeah I agree with your last point
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    (Original post by 3 Phase Duck)

    >Still the same biological makeup

    >the way our bodies react.. have changed.
    care to explain how that's possible? what is the logical biological plausability behind that?
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    (Original post by HFerguson)
    care to explain how that's possible? what is the logical biological plausability behind that?
    'Still the same biological makeup' means we like cavemen are homo sapiens sapiens. We are the same species, the dna is the same. Assuming you are talking about cave dwelling homo sapiens (or cave dwelling modern day humans).


    'The way our bodies react' means despite being the same species, our bodies react different to different things. I.e. a european homo sapien sapien is better adapted to living in colder climates than a subsahran african (all things being equal).
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    (Original post by 3 Phase Duck)
    No, the stresses and pressure don't drive the mutation. The mutations are seemingly completely random, it's the stresses and pressure that drive mutations onto the next generation i.e. a random mutation that mutates in a group that survives these pressures. It may seem like our environment causes the mutations but it's not, we are the way we are today because these mutations survived and thus drove the evolutionary process not, the evolutionary process drove us to mutate to the way we are today. We actually don't know what drive mutations, hence why evolution (as a whole) is still regarded as a theory and not a fact (or I suppose you can call it a law). We know evolution happens, but we don't know what are the mechanisms that cause change. Certainly it's never been proven that evolution happens because of the stresses of the environment.

    Infact the saying "survival of the fittest" comes from this, as it is the ones that survive that pass on thier traits to their offspring and thus shape the species. Like I said it's death in numbers that made us what we are today, it was those random mutation that were "lucky" enough to develope in the generations that happened to survive. It may well be that many mutations helped us survive, hence why europeans are better adapted to colder climates. But these mutations or adaptations weren't caused by the stresses that were killing us. If that were the case and it was our changing environment or the stresses of the environment that caused evolutionary mutations then today you could arguing the evolutionary process is starting to stop because we have less pressures in our environment meaning less need to adapt. However we know that evolution is still happening like it always has thus it can't be our harsh environment that causes mutations.

    Although now that you memtion it's only been 10,000 years since a change in diet thus perhaps not enough time for us to have changed that much does make sense. However I'm still skeptical of the whole "it was good for the cavemen" argument.

    Yeah I agree with your last point
    You've misread me. I didn't say that pressures drove the mutations to arise-I said that the pressures drive which mutations propagate. Basically the same as what you just tried to explain back to me :rolleyes:

    (Although an interesting point: why are DNA Polymerases inaccurate? Why wouldn't evolution cause them to become more and more accurate to aid survival? The answer is that there's a balance between increasing the polymerase's accuracy and being able to pass down the genes more faithfully, and decreasing the polymerase's accuracy to allow evolutionary change. In this way, evolutionary pressures actually do drive mutations because they push the accuracy of the polymerase down from perfect! A perfect polymerase would slow evolution because it would be restricted to things like recombination, which would slow the rate of genetic shift. But this is just a special case, you're correct in saying that evolutionary pressures do not directly cause any individual mutation to occur.)

    Random mutation, non-random reproduction. Selection pressures determine who survives, which determines which genetics are passed to offspring. It's not chance as you are almost implying in some areas.

    Genes that are unaffected by selection pressures stay (in general) at a constant % in a large population by chance alone. So if you have a pressure keeping a gene at 60% say, and the pressure is removed, it will stay at 60%. That's why the diet won't be significantly changed, at least not as quickly as the time period we have, because there is no significant pressure causing the optimal diet to change.

    We actually don't know what drive mutations, hence why evolution (as a whole) is still regarded as a theory and not a fact (or I suppose you can call it a law). We know evolution happens, but we don't know what are the mechanisms that cause change. Certainly it's never been proven that evolution happens because of the stresses of the environment.
    This is simply incorrect. We know that inaccurate DNA polymerases cause mutations, and we know that selection pressures cause some to propagate through a population better than others, hence are "naturally selected" for. We also know ways that mutations can occur-in meiosis, from radiation or oxidative stress, and non-mutative evolution in homologous recombination. There's also other areas I'm sure that I don't know about-I'm talking from the medical student perspective, not the biology student perspective. But it's still clear that we do know how mutations can arise.

    And "Theory" is the highest order of knowledge that science can provide without mathematical models. A Law is a different kind of knowledge, one that doesn't suggest a mechanism but instead describes observations, and so evolution can never be a "Law", it's not the right kind of knowledge.

    But these mutations or adaptations weren't caused by the stresses that were killing us. If that were the case and it was our changing environment or the stresses of the environment that caused evolutionary mutations then today you could arguing the evolutionary process is starting to stop because we have less pressures in our environment meaning less need to adapt. However we know that evolution is still happening like it always has thus it can't be our harsh environment that causes mutations.
    This is just incorrect, nobody would claim that evolution "stopped". As long as reproduction continues, evolution continues, because those that reproduce pass down those genes that have allowed them to reproduce in that environment. Yes, it's a set of vastly different genes to those that previously caused evolutionary change because we've drastically changed our environment, but we still have evidence that, for example, our prefrontal lobes are increasing in size, indicating evolution towards increased ability to predict events and plan based on them (ie: think).

    In summary: we are almost genetically identical to cavemen, there is no reason to suggest that the optimal diet has changed from that time. That isn't in support of IF, it's just in support of the logic behind IF, which is sound.




    (Original post by 3 Phase Duck)
    'Still the same biological makeup' means we like cavemen are homo sapiens sapiens. We are the same species, the dna is the same. Assuming you are talking about cave dwelling homo sapiens (or cave dwelling modern day humans).


    'The way our bodies react' means despite being the same species, our bodies react different to different things. I.e. a european homo sapien sapien is better adapted to living in colder climates than a subsahran african (all things being equal).
    How do you suggest the body reacts differently to the same stress when the DNA is "identical"? If our DNA is identical, we must react in exactly the same way. If our DNA is not identical, we don't have the exact same biological make up. Which statement are you withdrawing?
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    (Original post by Hypocrism)
    You've misread me. I didn't say that pressures drove the mutations to arise-I said that the pressures drive which mutations propagate. Basically the same as what you just tried to explain back to me :rolleyes:
    Well I must have not understood what you meant.

    (Although an interesting point: why are DNA Polymerases inaccurate? Why wouldn't evolution cause them to become more and more accurate to aid survival? The answer is that there's a balance between increasing the polymerase's accuracy and being able to pass down the genes more faithfully, and decreasing the polymerase's accuracy to allow evolutionary change. In this way, evolutionary pressures actually do drive mutations because they push the accuracy of the polymerase down from perfect! A perfect polymerase would slow evolution because it would be restricted to things like recombination, which would slow the rate of genetic shift. But this is just a special case, you're correct in saying that evolutionary pressures do not directly cause any individual mutation to occur.)

    Random mutation, non-random reproduction. Selection pressures determine who survives, which determines which genetics are passed to offspring. It's not chance as you are almost implying in some areas.[/QUOTE]

    I'm not sure what you mean by your last part.

    Genes that are unaffected by selection pressures stay (in general) at a constant % in a large population by chance alone. So if you have a pressure keeping a gene at 60% say, and the pressure is removed, it will stay at 60%. That's why the diet won't be significantly changed, at least not as quickly as the time period we have, because there is no significant pressure causing the optimal diet to change.
    Fair enough.

    This is simply incorrect. We know that inaccurate DNA polymerases cause mutations, and we know that selection pressures cause some to propagate through a population better than others, hence are "naturally selected" for. We also know ways that mutations can occur-in meiosis, from radiation or oxidative stress, and non-mutative evolution in homologous recombination. There's also other areas I'm sure that I don't know about-I'm talking from the medical student perspective, not the biology student perspective. But it's still clear that we do know how mutations can arise.
    Are these the same mechanisms that cause evolutionary mutations and not somatic mutations?

    And "Theory" is the highest order of knowledge that science can provide without mathematical models. A Law is a different kind of knowledge, one that doesn't suggest a mechanism but instead describes observations, and so evolution can never be a "Law", it's not the right kind of knowledge.
    I wasn't claiming evolution was a law. Infact I said it wasn't. I used the word law to justify my point for the reason why evolution isn't considered a fact, I wasn't trying to claim it could ever be a law. Although I was only doing this because i was in turn trying to justify my explantation when I thought you were trying to say pressures cause mutations.

    This is just incorrect, nobody would claim that evolution "stopped". As long as reproduction continues, evolution continues, because those that reproduce pass down those genes that have allowed them to reproduce in that environment. Yes, it's a set of vastly different genes to those that previously caused evolutionary change because we've drastically changed our environment, but we still have evidence that, for example, our prefrontal lobes are increasing in size, indicating evolution towards increased ability to predict events and plan based on them (ie: think).

    I know nobody would claim evolution would stop, that was the point I was trying to make.


    In summary: we are almost genetically identical to cavemen, there is no reason to suggest that the optimal diet has changed from that time. That isn't in support of IF, it's just in support of the logic behind IF, which is sound.


    How do you suggest the body reacts differently to the same stress when the DNA is "identical"? If our DNA is identical, we must react in exactly the same way. If our DNA is not identical, we don't have the exact same biological make up. Which statement are you withdrawing?
    Why are you quoting the word identical, I never said idenitcal.


    Neither. If we have the same dna as all homo sapiens share the same dna i.e. we are 99.9% the same. But we also know that europeans are better suited to the european environment than sub saharan africans. Our bodies react differently to the environment around us. But we are the same speicies, so it could be plausible to claim that what's good for a caveman might not necessarily be good for us in this age. We are the same species still, but it's also reasonable to suggest we have changed ever so slightly from then and our bodies react differently.
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    (Original post by HFerguson)
    want to rep this post but im all out of rep! I consider myself a "seasoned eater", and 3000kcal in one sitting is a push. It's just not possible to get 4000kcal in 5 hours. You'd be doing nothing but eating for the entire time, and then you'd feel nauseous and bloated, it's ****ing stupid.

    If you want more GH, then I would recommend you supplement it exogenously, if you know what im sayin...

    I don't think IF is a "magic bullet" that will unlock OMG SUPER LEAN GAINS MODE; if it fits your schedule better or you prefer it, great. Fasting probably is good for us, and the evidence base behind fasting and its beneficial effects is growing, but you shouldn't feel obliged to do something like IF. Do whatever you're happy and comfortable doing. "Little and often" may be the given advice but there's no evidence that this "stokes the metabolic fire" as so many claim. Meal frequency has no effect in that regards.
    It definitely is possible...

    http://www.youtube.com/watch?v=Zw8iljkD1So


    Obviously I'm not going to be eating like that, but I think you are overestimating how much 4000kcal is. I plan to workout early fasted, then come home and eat. My pre and post workout shake (with milk) will probably constitute about 1000kcal alone.
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    (Original post by TheCount.)
    It definitely is possible...

    http://www.youtube.com/watch?v=Zw8iljkD1So


    Obviously I'm not going to be eating like that, but I think you are overestimating how much 4000kcal is. I plan to workout early fasted, then come home and eat. My pre and post workout shake (with milk) will probably constitute about 1000kcal alone.
    I train fasted after 20 hours; I have my protein shake post workout then I can't eat for at least another hour, then I struggle to get in 2000kcal, but that's just me - I wish you the best of luck! "Just cos I can't do it doesn't mean it can't be done"
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    (Original post by Pegasus2)
    Actually, been thinking. It probably is possible to eat 4k's worth in that time frame but it's still a lot.

    I was thinking along the lines of 4x fried egg, 4x bacon, 4x fried bread...
    Okay, what about the other 3000 calories?
 
 
 
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