Intermittent fasting

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cornivore
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Joined: Wed Jun 20, 2018 3:23 am
Diet: Vegan

Re: Intermittent fasting

Post by cornivore »

Lots to consider! All together, it wasn't that simple, was it? Not even for the birds.
cornivore wrote: Fri Aug 24, 2018 7:21 pm I have to wonder, if the snake diet is a 22 hour intermittent fast, then what does a 48 hour one correspond to in the wild kingdom? I suppose it's more like a vulture diet. They'll typically eat every two or three days. Oddly enough there's a disturbing story to this. Vultures that feed most often are more likely to die when a carcass is poisoned by veterinary drugs. A decline in vulture populations has occurred recently because of this... I guess how ever long someone is comfortable fasting between meals, more power to them...
This is where striking a balance could be tricky. Since I was looking further into Adulterated food, etc. (pardon my french); it's an example of how people might be in a similar situation to the vultures (having adulterated food in common, in one way or another).

Well then, how do people respond to longer fasts? A recent study on periodic fasting indicates that it is "safe and well tolerated" for the average person (in a medical setting, at least), and that they feel better throughout the process. It does not end at fasting, though (in order to take refeeding syndrome into consideration) with a "stepwise re-introduction of solid food thereafter"... I'd like to emphasize that people may respond most adversely to how they eat afterward, keeping in mind that food can be more acutely disruptive to a person than starvation (this is the bad news before the good news, hypothetically, if periodic fasting ended at the buffet table).
In conclusion, this one-year observational study demonstrates the safety of a periodic Buchinger fast of between 4 and 21 days, as well as its beneficial effects on health and well-being. Periodic fasting led to marked weight loss and improvements in several cardiovascular risk factors, such as overweight, abdominal circumference and blood pressure. It was accompanied by normalization of numerous blood parameters and led to pronounced improvement of the major health complaint in most participants. Importantly, periodic Buchinger fasting was not linked to relevant perception of hunger. On the contrary, it was subjectively experienced as enjoyable, which is an important factor for compliance.

—Safety, health improvement and well-being during a 4 to 21-day fasting period in an observational study including 1422 subjects
Another recent study on periodic fasting measured muscle loss in an individual, which seems to confirm that it is more likely to occur with longer than intermittent fasts. The previous study I looked at (Adaptive Response to Fasting) says "when fasting is continued, muscle protein catabolism declines", however it doesn't appear to have declined after a few days (as mentioned there), in this case. So I guess individual results may vary.
One subject participated in a 14-day periodic fast (PF) under daily supervision of nurses and specialized physicians, ingesting a highly reduced intake: 200 Kcal/day coupled with active walking and drinking at least 3 L of liquids/day. The fasting was preceded by a 7-day pre-fasting vegetarian period and followed by 14 days of stepwise reintroduction of food.

During the fasting period, body weight (BW) decreased by −7.9 kg (9.5% of total mass). After the refeeding period, BW remained −4.7 kg (−5.7%) at 4 months. These BW changes were associated with a whole quadriceps muscle volume changes of −30mm3 (−3.2%) after fasting and −41mm3 (−4.4%) after re-feeding.

—Long-Term Multi-Organs Composition Changes of a 14-Days Periodic Fasting Intervention...
Between the two concepts, I'd think that if a person (or a vulture) could eat less at a time, with one or two days of fasting in between feeding, it would reduce exposure to adulterants (as would eating more, with a longer interval in between, i.e., feast and famine). Vultures don't necessarily have that luxury, or thought process. Neither do people, typically, but I'm thinking that would be a good balance, if possible. It seems that people on periodic fasts feel okay while losing muscle, somehow, but they're just walking around in a controlled setting, and may need more strength to do other things, like maintaining thermoregulation in adverse weather (and control of the mind and body, for safety especially). I'm also thinking that "adulterants" come in many forms, as the physical state of being of those periodic fasters was normalized while they were not eating for an extended period of time, so keeping one's exposure to food (in general) to a minimum could be best for intermittent fasting also. In that way, it could be thought of as the mimicry of periodic fasting, by reducing the amount of food eaten, yet involve enough nutrients to maintain musclular conditioning, without one becoming underweight (having eaten frequently enough, yet infrequently too). Vultures have a large wingspan to conserve energy to that effect, so I think it can be a natural balance in principle (if people were somehow conserving energy in the process). Obviously people tend to conserve more than enough energy to become overweight, so I think it's a fair comparison either way.

Although, human adaption to cooked food is thought to be the kind of efficiency gain that allowed them to develop larger brains (so I'm not comparing them to vultures by diet, just its adulteration, and conservation otherwise).
Despite a general trend for larger mammals to have larger brains, humans are the primates with the largest brain and number of neurons, but not the largest body mass. Why are great apes, the largest primates, not also those endowed with the largest brains? Recently, we showed that the energetic cost of the brain is a linear function of its numbers of neurons. Here we show that metabolic limitations that result from the number of hours available for feeding and the low caloric yield of raw foods impose a tradeoff between body size and number of brain neurons, which explains the small brain size of great apes compared with their large body size. This limitation was probably overcome in Homo erectus with the shift to a cooked diet. Absent the requirement to spend most available hours of the day feeding, the combination of newly freed time and a large number of brain neurons affordable on a cooked diet may thus have been a major positive driving force to the rapid increases in brain size in human evolution.

—Metabolic constraint imposes tradeoff between body size and number of brain neurons in human evolution
So cooking food can allow one to conserve more energy, and also reduce its health risks (as noted in the topic on raw food). Personally I've confirmed this by gaining weight lately while cooking more for the sake of experimentation (without adverse effects otherwise). Kind of a Polynesian style vegan cuisine, with seasonings for basic taste, but no spices (and I don't really miss them). I was also reading We, the Tikopia, for comparison. It is an ancient tradition, actually. I'm pretty sure it compliments the fasting traditon (We, the Tirthankara, so to speak)...
Jebus wrote: Thu Jun 29, 2017 2:47 am However, does it make a difference if one eats 20 percent fewer meals or if one eats all meals but with 20% less food?
Not to go off on a tangent there, except I think it depends on this, that, and the other. ;)
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