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Fasting triggers stem cell regeneration of damaged, old immune system (2014)

news.usc.edu

11–20 of 175 posts

Re: Fasting triggers stem cell regeneration of damaged, old immune system (2014)

#11

Although I haven't attempted this myself, I have seen many people attempt to endure a 72 hours fast (as part of diagnosing a potential pheochromocytoma) and the majority experience this as extremely difficult. I wonder if multiple shorter fasts — e.g., a 24 hours fast once a week — could be as beneficial.

I have fasted for approximately a week on 4 different occasions and interestingly enough the 72 hours that you mentioned are indeed the hardest. For me personally it started getting easier at that specific 72 hour mark.

In regards to the multiple 24 hours fast I was wondering the same thing reading this article. Although I think it might not work because of the white blood cells regenerating.

Re: Fasting triggers stem cell regeneration of damaged, old immune system (2014)

#12

Do they literally mean zero intake of calories for 72 hours? That sounds like a long time. How do you prepare for that nutrition wise and mentally? People eat at night during the ramadan.

About 3 years ago, I undertook a water fast that lasted about 17 days. It does take a lot of mental preparation. Nutrition wise, I ate only fruits for about a week before the fast. The first few days were very hard, but then I simply did not feel hunger at all. I intended to continue the fast for 30 days. But from about the 4th day onwards my mouth started having an awful odour and my tongue had a thick white coating that was the source. Into the third week, I simply couldn't bear that smell anymore and gave up. for getting back to regular food, I did the same thing and had only juices and fruits for about 3-4 days.

Now, I'm not an expert, but I read while preparing for the water fast that your body has nutrients it needs to survive for a few weeks. I didn't take any supplements during that time. Unfortunately, at that time i didn't have the means to measure and quantify what changed after the fast. I do remember being in a great mood for a few days after the fast. I don't know how much it benefited me, but it was an interesting exercise

Re: Fasting triggers stem cell regeneration of damaged, old immune system (2014)

#13

Although I haven't attempted this myself, I have seen many people attempt to endure a 72 hours fast (as part of diagnosing a potential pheochromocytoma) and the majority experience this as extremely difficult. I wonder if multiple shorter fasts — e.g., a 24 hours fast once a week — could be as beneficial.

I regularly fast for 20+ hours (calorie restriction, I do drink water because I am not an idiot) once or twice a week. You get very used to it.

While its not something I look forward to, it's purely psychological. A few hours after I miss 'breakfast' my tummy rumbles two or three times and then my body doesn't care anymore.

The max time I've fasted is forty hours and I have to say if you can get past the first fours hours, it's easy. I didn't really plan to fast that long, circumstances led to it. I actually found it hard to eat after it. I normally eat a very small 500-600 calorie meal after a fast but I couldn't finish it after the long fast.

I think we underestimate how adaptable our body is and how intermittent fasting is actually the norm for most mammals.

Re: Fasting triggers stem cell regeneration of damaged, old immune system (2014)

#14

Although I haven't attempted this myself, I have seen many people attempt to endure a 72 hours fast (as part of diagnosing a potential pheochromocytoma) and the majority experience this as extremely difficult. I wonder if multiple shorter fasts — e.g., a 24 hours fast once a week — could be as beneficial.

I have fasted for approximately a week on 4 different occasions and interestingly enough the 72 hours that you mentioned are indeed the hardest. For me personally it started getting easier at that specific 72 hour mark. In regards to the multiple 24 hours fast I was wondering the same thing reading this article. Although I think it might not work because of the white blood cells regenerating.

I don't think that's fasting any more, sounds more like starvation, to me.

Re: Fasting triggers stem cell regeneration of damaged, old immune system (2014)

#15

Do they literally mean zero intake of calories for 72 hours? That sounds like a long time. How do you prepare for that nutrition wise and mentally? People eat at night during the ramadan.

About 3 years ago, I undertook a water fast that lasted about 17 days. It does take a lot of mental preparation. Nutrition wise, I ate only fruits for about a week before the fast. The first few days were very hard, but then I simply did not feel hunger at all. I intended to continue the fast for 30 days. But from about the 4th day onwards my mouth started having an awful odour and my tongue had a thick white coating…

That odour is probably the ketones coming into play when the body starts using fat for energy, instead of carbs or protein. And yes, it's a well known fact.

Re: Fasting triggers stem cell regeneration of damaged, old immune system (2014)

#16

Earlier quoted context omitted.

Probably there is some minimum, because when you drink just regular water that has some calories as well. And not drinking for a day might be he worst dietary idea ever. UPDATE: Water doesn't contain calories. Sorry for the misinformation. My mouth (actually my hands) was faster then my brain. :-)

Please explain where the calories in plain water come from.

According to mass-energy equivalence, every gram of water contains ~2.15*10^13 calories.

Re: Fasting triggers stem cell regeneration of damaged, old immune system (2014)

#17
I tried searching for the original article, but this is the closest I could find that had a better writeup than from the telegraph: https://news.usc.edu/63669/fasting-triggers-stem-cell-regene...

This is the most relevant summary: "In both mice and a Phase 1 human clinical trial involving patients receiving chemotherapy, long periods of not eating significantly lowered white blood cell counts. In mice, fasting cycles then “flipped a regenerative switch,” changing the signaling pathways for hematopoietic stem cells, which are responsible for the generation of blood and immune systems, the research showed."

So, mice, and people undergoing chemotherapy. Not exactly (for those who have had friends and relatives ever had to undergo chemotherapy, you will understand what I mean) the common population.

I'll pass on this intermittent fasting "fad" for now!

Re: Fasting triggers stem cell regeneration of damaged, old immune system (2014)

#20

Earlier quoted context omitted.

Please explain where the calories in plain water come from.

According to mass-energy equivalence, every gram of water contains ~2.15*10^13 calories.

I think you're missing an algebraic sign there.
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