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Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

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Re: Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

#81

Post by argyleaf »

CamperBob2 wrote: post #70
rsync wrote: post #64

Earlier quoted context omitted.

"I'm personally very skeptical [as well]. I notice that almost nobody that recounts their fasting experience ever mentions sport." Allow me to step right up. First, as you might expect, aerobic and endurance exercise benefits greatly from being in a fasted (16-24 hr) state. You're light, quick and your body is devoting zero blood flow (and other resources) to digestion. I suspect you're not surprised by this. Second,…

First, as you might expect, aerobic and endurance exercise benefits greatly from being in a fasted (16-24 hr) state If that's true, why isn't it a universal practice in amateur and professional athletic competition? (Or, for that matter, why isn't it banned?)

I can't speak to endurance (I got into IF after my endurance-athlete days) but I know that body weight-based athletes do this to perform better. My experience is specific to rock climbing.

When you are right at the edge of your abilities being just a couple pounds lighter can feel like a world of difference (people hone down their rack to precisely what they need for a route, nothing more), especially on sport and boulder problems. My anecdata points to it being great for the project/performative aspects of the sport but as a tool for consistent progression/improvement, I am less confident in stating anything.

Re: Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

#82

Post by jacques_chester »

49para wrote: post #30
dvt wrote: post #17

I fast, on average, once a week. At least once a month, I try to do an extended fast (2-5 days) to force ketosis. I also do intermittent fasting basically daily (I only eat between 12-8). Been doing this for about 4 years now. Some anecdata: - Fasting > 24 hrs paradoxically gives you an extreme boost of energy and mental focus. I especially love how my olfactory sense is extremely heightened. It's pretty cool and eve…

Why would your body breakdown your organs when you still have plenty of adipose stores ? Do you have a citation for the "starvation mode" ? If it's the 1940's study from MN, that was only when the subjects where well into single digit fat %.

Bodies aren't finite state machines and the concept of "modes" can be misleading. What you have is a (very large) number of independent processes that have differing amounts of flow under different conditions.

So, for example, you don't click from building muscle to consuming muscle. What happens is that catabolism has a higher flow than anabolism, so the net balance is negative.

As the body becomes leaner in starvation conditions, processes that recover energy from gluconeogenesis or from lipolysis cannot produce "enough" energy. So feedback loops that suppress the breakdown of organ tissue weaken and eventually that loop shifts.

Re: Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

#84

Post by rsync »

fauigerzigerk wrote: post #72
rsync wrote: post #62

Earlier quoted context omitted.

"Unfortunately, eating healthy is hard and kinda' sucks. Egg whites and chicken + broccoli gets old pretty fast." I welcome any opportunity to point to almond butter as an extremely dense, and healthy, source of calories. Easy to add to a smoothie. Speaking more broadly, I would have a hard time with IF, etc., were it not for shifting about 20-30% of my calorie input to nuts, generally. Mostly raw in form.

>shifting about 20-30% of my calorie input to nuts I wouldn't do that. Nuts contain tons of metals that you don't want to overdose on.

"According to the finding of the research, any amount of Pb, Hg and Sn were not detected in the organic certified nuts. In the organic certified nuts, the levels ranged between 5.53-123.78 ppb Cd, 8.22-16.62 ppm Cu, 0.24-1.86 ppm Ni, 15.03-46.37 ppm Zn, 444.1-810.6 ppb Cr, 22.06-67.42 ppm Fe and 1.24-3.14 ppb As."[1]

Perhaps you are speaking of conventional (non organic) nuts and seeds ? I would not consider consuming those.

[1] https://www.cabdirect.org/cabdirect/abstract/20183271188

Re: Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

#85

Post by jniedrauer »

torben-friis wrote: post #35
dvt wrote: post #17

I fast, on average, once a week. At least once a month, I try to do an extended fast (2-5 days) to force ketosis. I also do intermittent fasting basically daily (I only eat between 12-8). Been doing this for about 4 years now. Some anecdata: - Fasting > 24 hrs paradoxically gives you an extreme boost of energy and mental focus. I especially love how my olfactory sense is extremely heightened. It's pretty cool and eve…

Are you fit? as in, do you lift weights or are active in sports that require strength? I ask because I wonder about the effects of extended fasts on muscle loss/retention, a big problem cutting weight for some people is that they get rid of some muscle mass along with the calories they wanted to eliminate.

I can speak to this a bit. I practiced intermittent fasting (eating once per day) for nearly a decade, while maintaining a very low activity level. My resting metabolic rate dropped significantly during this time (down to about 1300 kcal/day).

About a year ago, I increased my activity level significantly (distance running, hiking, strength training, cycling) and quickly found that:

a) I wasn't recovering quickly enough

b) It was extremely difficult to take in enough calories for a day in a single meal

c) I had very low energy when in ketosis

Eventually I gave up and just started eating on a typical 3-4 meal a day schedule. My RMR steadily increased back to baseline, I got a lot more explosive energy, my body began responding much more rapidly to training, and my recovery speed improved significantly.

Personally I think that intermittent fasting is not a good idea if you are very physically active. That's just my opinion from my own experience.

Re: Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

#86

Post by itchyouch »

davinic wrote: post #26
dvt wrote: post #17

I fast, on average, once a week. At least once a month, I try to do an extended fast (2-5 days) to force ketosis. I also do intermittent fasting basically daily (I only eat between 12-8). Been doing this for about 4 years now. Some anecdata: - Fasting > 24 hrs paradoxically gives you an extreme boost of energy and mental focus. I especially love how my olfactory sense is extremely heightened. It's pretty cool and eve…

Can you point to any studies that show the benefits of your vitamin regimen? You point out there are no studies on long term fasting but I am also unable to find the studies on the benefits of vitamins.

When it comes to vitamins, the typical, North American diet is likely deficient based on the following behaviors.

  I am inside all day and get no sun - Vitamin D
  I do not eat wild caught fish - Omega 3s
  I am vegan - B12
  I do not eat greens daily - Multivitamin + Magnesium Theronate/Glycinate
Most people are D & Omega 3 deficient. Also a bulk of folks are Magnesium deficient unless they are eating greens daily.

Re: Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

#87

Post by jodrellblank »

jniedrauer wrote: post #85
torben-friis wrote: post #35

Earlier quoted context omitted.

Are you fit? as in, do you lift weights or are active in sports that require strength? I ask because I wonder about the effects of extended fasts on muscle loss/retention, a big problem cutting weight for some people is that they get rid of some muscle mass along with the calories they wanted to eliminate.

I can speak to this a bit. I practiced intermittent fasting (eating once per day) for nearly a decade, while maintaining a very low activity level. My resting metabolic rate dropped significantly during this time (down to about 1300 kcal/day). About a year ago, I increased my activity level significantly (distance running, hiking, strength training, cycling) and quickly found that: a) I wasn't recovering quickly enou…

There is a range of IF between one meal per day, and not doing it at all. Prof Sachin Panda’s research on mice shows effects of 12hrs/12hrs, 8hrs eat/16hrs fast, and fasting some days but not every day.

Did you experiment with any other patterns?

Re: Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

#88

Post by ksaj »

dvt wrote: post #37
49para wrote: post #30

Earlier quoted context omitted.

Why would your body breakdown your organs when you still have plenty of adipose stores ? Do you have a citation for the "starvation mode" ? If it's the 1940's study from MN, that was only when the subjects where well into single digit fat %.

You can see that there was protein turnover just after 10 days in rats: https://www.ncbi.nlm.nih.gov/pubmed/7119891 In healthier rats, protein turnover (cannibalizing muscles / organs) was faster than in obese rats. I had some human studies bookmarked, I'll try to find them again. There were a few ketosis studies that discussed "starvation mode" so maybe try searching for that.

> I had some human studies bookmarked, I'll try to find them again.

Please do. Rat studies are helpful, but not definitive-- close but not exact. That's why it takes so long for medicines and therapies that are shown to absolutely work on rats still take forever to reach humans.

Re: Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

#89

Post by mikeklaas »

dvt wrote: post #80
whycombagator wrote: post #77

Earlier quoted context omitted.

> Egg whites and chicken + broccoli As an aside, a meal consisting of just this isn't very balanced. There is effectively 0 fats in it. Egg yolks are actually quite healthy and would have rounded this meal off nicely

My daily intake was 175g protein, 150g carbs, and 50g fats. To hit those macros reliably, egg whites for breakfast and chicken (or tuna) for dinner will quickly become a status quo :)

That's an insane macro ratio for most people, though. You don't need that much protein unless you're doing some intense weight training.

Re: Alternate Day Fasting Improves Physiological and Molecular Markers of Aging [pdf]

#90

Post by [deleted] »

l_t wrote: post #76
pizza234 wrote: post #59

Earlier quoted context omitted.

I'm personally very skeptical [as well]. I notice that almost nobody that recounts their fasting experience ever mentions sport. I personally found very hard already to progress on weightlifting during diet cycles, as I need to cut on volume significantly; can't imagine to do that while fasting, unless fasting would "flip a switch" in how the (my) body works, which I doubt.

I've experimented with fasting and weightlifting and I want to share some thoughts. First, fasting does not require that your overall calorie intake is reduced. If your cut-goal is 2000kcal per day, you can fast in the morning and eat all 2000kcal in the afternoon. Ultimately, I find this is actually an easier and less hunger-inducing way to each your cutting goals. Second, you're right. Doing weightlifting while fas…

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