The Core
Why We Are Here => Water Cooler => Topic started by: rcjordan on May 06, 2018, 02:14:47 PM
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hat tip to Gimp's SO for first bringing up fasting as worth watching
I'm seeing enough reliable/authoritative study results to merit starting a thread.
MIT: Age-related loss of stem cell function can be reversed by a 24-hour fast
http://news.mit.edu/2018/fasting-boosts-stem-cells-regenerative-capacity-0503
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https://www.allaboutfasting.com/effects-of-fasting-ketosis.html
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Autophagy, and now evidence of stem cell repair -- it makes sense from an evolutionary perspective that nature would learn to take advantage of the feast and famine cycles of non-modern living.
It should be noted though that 24 hours for a mouse is probably a lot different than for a human -- that might be the equivalent of a four day fast for us.
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>equivalent of a four day fast for us.
I saw several articles prior to this one referenced another study. 3-day fasts kicked it in gear for humans, IIRC.
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There's a lot here, but this is the Rhonda Patrick QA where she was talking about fasting
https://tim.blog/2017/05/04/smart-drugs-fasting-and-fat-loss/
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https://vimeo.com/170735109
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Seen on Twitter:
Fasting made me realize that i eat so much just cause im bored
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I recall seeing something about people who don't eat a lot but right at the margin of what they need, tend to live longer.
There's a lot of misinformation surrounding food, too.
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I recall seeing something about people who don't eat a lot but right at the margin of what they need, tend to live longer.
But now researchers have published the results of an over two-decade study of caloric restriction in monkeys in Nature. And it turns out that the starving monkeys didn't live any longer than the monkeys who ate until they were satisfied.
https://io9.gizmodo.com/5939162/turns-out-those-longevity-maniacs-were-wrong-about-how-to-live-to-be-800-years-old (2012)
Better article
The results of this major, long-awaited study, which began in 1987, are finally in. But it did not bring the vindication calorie restriction enthusiasts had anticipated. It turns out the skinny monkeys did not live any longer than those kept at more normal weights. Some lab test results improved, but only in monkeys put on the diet when they were old. The causes of death — cancer, heart disease — were the same in both the underfed and the normally fed monkeys.
https://www.nytimes.com/2012/08/30/science/low-calorie-diet-doesnt-prolong-life-study-of-monkeys-finds.html
And way back in 2005, Aubrey de Grey guesstimated (really, truly, this was a purely theoretical argument) that caloric restriction would only increase lifespan by a small amount (2-3 years).
https://www.ncbi.nlm.nih.gov/pubmed?term=15711074
Oh, and let's not forget the results of the Minnesota Semi-Starvation experiment (1944-45), where subjects were first put on a 3200 calorie diet for 12 weeks and then on a 1560 calorie diet for 24 weeks (which is pretty close to what I've seen suggested for caloric restriction)
Among the conclusions from the study was the confirmation that prolonged semi-starvation produces significant increases in depression, hysteria and hypochondriasis as measured using the Minnesota Multiphasic Personality Inventory. Indeed, most of the subjects experienced periods of severe emotional distress and depression.[1]:161 There were extreme reactions to the psychological effects during the experiment including self-mutilation (one subject amputated three fingers of his hand with an axe, though the subject was unsure if he had done so intentionally or accidentally).[6] Participants exhibited a preoccupation with food, both during the starvation period and the rehabilitation phase. Sexual interest was drastically reduced, and the volunteers showed signs of social withdrawal and isolation.[1]:123–124 The participants reported a decline in concentration, comprehension and judgment capabilities, although the standardized tests administered showed no actual signs of diminished capacity. This ought not, however, to be taken as an indication that capacity to work, study and learn will not be affected by starvation or intensive dieting. There were marked declines in physiological processes indicative of decreases in each subject's basal metabolic rate (the energy required by the body in a state of rest), reflected in reduced body temperature, respiration and heart rate. Some of the subjects exhibited edema in their extremities, presumably due to decreased levels of plasma proteins given that the body's ability to construct key proteins like albumin is based on available energy sources.
https://en.wikipedia.org/wiki/Minnesota_Starvation_Experiment#Results
Fasting? Sure.
Long-term caloric restriction? As my grandmother told her doctor when she was 89 and the doctor told her she had to give up ice cream or she would die: "Well, frankly, I'd rather be dead then."
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>significant increases in depression
I too would be depressed if forced to lose 25% of my body mass in 24 weeks while eating war rations of bread and potatoes "designed to induce the same level of nutritional stress for each participant."
I wonder if a CR study with goal of improving blood bio-markers, coupled with a nutrition-packed diet of fresh veggies / fruit / proteins and healthy fats would produce significantly fewer psychological side effects.
Most Americans would benefit from some caloric restriction.
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I wonder if a CR study with goal of improving blood bio-markers, coupled with a nutrition-packed diet of fresh veggies / fruit / proteins and healthy fats would produce significantly fewer psychological side effects.
Of course, they can't ask the monkeys about depression, but they don't seem to have benefited.
But of course, if you put most Americans on a diet designed to improve bio-markers and loaded it up with veggies, proteins and healthy fats and removed junk food and sugar and all that crap, you probably wouldn't need caloric restriction to see excellent results.
Most Americans would benefit from some caloric restriction.
Well, there is that.
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Dr. Stephen Phinney - 'Metabolic Effects of Fasting: A Two-Edged Sword' (https://www.youtube.com/watch?v=_1r8ffLDFcE) -- Low Carb Down Under youtube channel
https://blog.virtahealth.com/science-of-intermittent-fasting/ text version
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Some of that article is really interesting stuff, but I think overall they're looking for the wrong results.
>any regimen involving fasting beyond 24-hours has not been proven effective in sustaining weight loss long term.
It's not supposed to be about weight loss, right? It's about autophagy, increasing insulin sensitivity, etc...
>The other obvious safety concern with fasting, whether intermittent or sustained, is its effects on medication requirements to manage diabetes .... medication requirements for adequate blood glucose control are dramatically reduced in just the first day or two of fasting or carbohydrate restriction
>Similarly, blood pressure is often markedly reduced in just the first few days of fasting
One doctor's concern is another doctor's desired outcome?
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As shown above, net protein breakdown begins within the first day of fasting, reaches its maximum rate within 2-3 days – typically a pound of lean tissue lost per day
That's a lot of lean tissue to lose. That's more than I thought and something I've been wondering about. Thanks very much for posting.
@Travoli - it sounds like they are responding to a certain amount of bro science that they want to refute, which is why they focus on the weight loss part. I agree - who cares? But actually, until recently, many if not most of the articles I've seen on intermittent fasting focus on the weight loss component. You may be stuck in your "informed person who actually reads" filter bubble again. It's a terrible burden ;-)
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@Trav again - check out their author pages. They are not always focused on weight loss
https://blog.virtahealth.com/author/jeffvolek/
Interesting, I just realized what company this is. A friend who is diabetic who has been managing his condition primarily through a ketogenic diet and also happens to be a software engineer just took a job there. He is really excited about the place and their work.
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>not always focused on weight loss
Lately, the new hotness has been on resetting the immune system by fasting.
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>many if not most of the articles I've seen on intermittent fasting focus on the weight loss component. You may be stuck in your "informed person who actually reads" filter bubble again. It's a terrible burden ;-)
Ugh.
BTW I don't think fasting is a panacea. Seems like it can be a great tool, situationally, by educated patients for certain goals. The weight loss industry has discovered it. Here comes a tsunami of overgeneralizations, misrepresentations and misapplications.
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The authors of that article are really only focused on helping diabetics manage their diabetes with no or very little insulin through a ketogenic diet.
The fact that they feel compelled to write an article about fasting, weightloss, and "nutritional ketosis" indicates that the tsunami is already coming.
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People fast during Ramadan to develop empathy for others, for example.
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The article and the lecture have a slightly different focus, in the lecture they get into some studies that examine metabolic damage from longer fasts. It seems that suggestions that fasts longer than 48 hours can reduce lean body mass.
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The day after Dr. Stephen Phinney's lecture Megan Ramos (who works with Dr. Jason Fung) outlines their fasting program and responds to Phinney's concerns. (https://www.youtube.com/watch?v=EY3cHwOyCmw) -- another high quality Low Carb Down Under lecture.