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Thread: Big myth (?)... Missing meals -> Starvation -> body stores fat & slows metabolism ! page

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    OnlyBodyWeight's Avatar
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    Big myth (?)... Missing meals -> Starvation -> body stores fat & slows metabolism !

    Primal Fuel
    Everyone parrots this adage like it's Gopsel, but does anyone have any study proving this?

    This is the justification for eating breakfast, for example. .....(sound familiar?) "Otherwise, your body goes into starvation mode, and then you start to hoard fat (and slow the metabolism) b/c the body doesn't know where the next meal is coming from"

    While it sounds logical, this is not real science.
    Anyone have links to a study (ie: scientific proof) this junk-science is actually true?

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    Well the 6 meals is better than 3 isn't true, at least in this case of an "energy deficit". I don't know if I would be so bold to try to extrapolate 6 vs 3 to 3 vs 2 or 1 but it doesn't make any evolutionary sense to lower metabolism after only hours, humans aren't built to eat any arbitrary number of times like 3 or 2 or 6 times in a day, just to want to eat when it is imperative to survival and optimal functioning. It might make sense after a day or more that things would slow down and I suppose it would depend on perceived energy and food availability, so there is no absolute. Someone who used to weigh 300 pounds but was able to rapidly restore their leptin sensitivity and accumulate a good store of nutrients may very well go a long time, even a week or more just burning through the superfluous fat stores, whereas a very thin person may not do so well. It seems silly that twice a day would lower metabolism. If there was such a study that demonstrate it, they would have to control very things like insulin resistance and circulating leptin. I would also like to see such a thing.

    So I haven't really answered your question. Just speculated like a madman
    Stabbing conventional wisdom in its face.

    Anyone who wants to talk nutrition should PM me!

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    There's plenty of studies validating intermittent fasting. I don't need one invalidating "starvation mode" any more than I need to read about healthy whole grains. Skipping meals helps me. Skipping meals screws others up. Either can be perfectly primal.

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    Here is one of the more pointed studies I have looked at. If anything it makes me very excited about IF, and not at all worried about extending some fasts to break plateaus.

    If you scroll down to 2.1 you find this little gem:
    Although prolonged total starvation is associated with an absolute reduction in basal metabolic rate (BMR), during the first 2 days of starvation there is often a small absolute increase in BMR relative to values obtained after an overnight fast (Figure 1).
    This is my experience I am cautious to discuss because we are all different. But my metabolism increases if when I extend intermittent fasts. I have to be careful to eat before it down regulates, but herein lies the weight loss power of IF, imo.

    Lyle McDonald had this to say when asked the starvation mode question:
    Well there is no doubt that the body slows metabolic rate when you reduce calories or lose weight/fat. There are at least two mechanisms for this.

    One is simply the loss in body mass. A smaller body burns fewer calories at rest and during activity. There's not much you can do about that except maybe wear a weighted vest to offset the weight loss, this would help you burn more calories during activity.

    However, there's an additional effect sometimes referred to as the adaptive component of metabolic rate. Roughly, that means that your metabolic rate has dropped more than predicted by the change in weight.

    So if the change in body mass predicts a drop in metabolic rate of 100 calories and the measured drop is 150 calories, the extra 50 is the adaptive component. The mechanisms behind the drop are complex involving changes in leptin, thyroid, insulin and nervous system output (this system is discussed to some degree in all of my books except my first one).

    In general, it's true that metabolic rate tends to drop more with more excessive caloric deficits (and this is true whether the effect is from eating less or exercising more); as well, people vary in how hard or fast their bodies shut down. Women's bodies tend to shut down harder and faster.

    But here's the thing: in no study I've ever seen has the drop in metabolic rate been sufficient to completely offset the caloric deficit. That is, say that cutting your calories by 50% per day leads to a reduction in the metabolic rate of 10%. Starvation mode you say. Well, yes. But you still have a 40% daily deficit.
    So even if you do buy into starvation mode, which I do not mostly in protest of the melodramatic terminology, you still cannot slow your metabolism down to the point of an energy balance. You will continue to lose weight. Obviously, the implications for lean people are to exercise more caution than fat people.

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    I have read somewhere that skipped meals can increase cortisol production - but I didn't see any 'why' - whether it's to do with metabolism, or if people simply feel a bit stressed because they are hungry. I think there's a different between simply skipping a meal and a more extended fast, too.

    Personally I like to have my evening meal early and skip breakfast with the view that it gives my digestive system a good long rest.

    This is interesting
    http://www.ncbi.nlm.nih.gov/pubmed/7202017

    There's also this, but I don't know about Grehlin yet
    http://jcem.endojournals.org/cgi/con...tract/90/2/741

    Have you checked out Mark's post about IF? Undoubtedly he'll have some data.

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    Relationships between diurnal plasma cortisol peaks and meals were evaluated for 30 male subjects divided into 5 groups. At 1300 h, at the time of a slow increase of plasma cortisol in fasting subjects, a reproducible rapidly increasing meal-related peak appeared in all subjects studied. An identical meal at 2000 h led to a lower mean response, with larger interindividual variations. This attenuated evening response does not seem attributable to any daily rhythm in responsiveness nor to changing basal levels, since only slight nonsignificant rises in cortisol appeared after an identical meal at 1000 h. The usual mean cortisol pattern with a midday peak was observed in subjects accustomed to different activity and meal-time schedules, which excludes the role of dietary habits. Satiety did not seen to play a determining role in the response to the 1000 h meal, as was shown by comparing subjects who did or did not have breakfast after overnight fasting. Meal intake was not necessary to provoke peaking in cortisol levels, and it has been established that neural and behavioral factors associated with meal presentation play a predominant role in some subjects. The results given clear evidence of the influence of meal timing on the daily plasma cortisol pattern, but no clue was found as to why eating affects the pituitary-adrenal axis differently according to the time of day. The noon meal may at least have a synchronizing role on normally existing plasma cortisol fluctuations.

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    yes but what does it MEAN

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    I've heard people discuss starvation mode when dieting for long periods of time, but not after a meal, that seems rather ridiculous. It's difficult to expect our metabolism to be reduced enough that weight loss stops completely. Like the saying goes, try and find a fat prisoner of war.

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    it takes years for the body to get into starvation mode and unless someone develops anorexia then it is so unlikely to happen its not even a worry.

    as far as fasting, if you dont have stress in your life, have healthy adrenals and cortisol levels, and a good thyroid youll reap all the benefits from it. otherwise, i would highly NOT recommend it for anyone.

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