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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]

#61

Post by pizza234 »

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 %.

This phenomenon (specifically, body breaking down muscles), is a very practical, and doesn't really need studies.

When doing bodybuilding (or sports in general), one can very easily measure their own bodyfat, and losing more muscle than fat is the enemy #1 during diet cycles (whose objective in fact is to minimize muscle loss and maximize fat loss).

Of course, "plenty of adipose stores" is relative. I guess that if one is 30% BF and never does any activity, as soon as they start to lift some weights, they'll put muscles and lose fat quickly for some time, independently of the calories deficit.

The other exception is when one takes anabolic steroids.

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

#62

Post by rsync »

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…

"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.

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

#63

Post by throwaway_law »

mytailorisrich wrote: post #56
throwaway_law wrote: post #40

Earlier quoted context omitted.

- Even on fast days, make sure you take vitamins (I take Fish Oil, Zinc, a Multivitamin and Magnesium) I have done some fasting recently (water, some water/apple cider vinegar in the morning; coffee, green tea, Ooolong tea), and have a similar vitamin intake (B complex; calcium/D combo; Magnesium; Zinc; Iron; Fish Oil). During the fasting I don't take the Fish Oil, I haven't read anything about it specifically, but j…

In general with a good diet there is no need to continuously take vitamin supplements.

In my case I am an endurance athlete, so at minimum supplementing electrolytes is helpful (also during the fast electrolyte supplements have at least seemed beneficial to my experience). Also, most American's are low on Vitamin D, and trust me I prefer it from the sun myself, but currently Im an office worker, so I supplement that.

Anecdotally, I can tell you that historically I used to get sick 2-3 times a year minimum, and since I began taking vitamins 5 years ago I got sick 1 time.

But I do generally agree with you about vitamins and minerals coming from diet over supplements, but I also say if you can get all your vitamins and minerals from food, your just not running enough (thats a joke).

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

#64

Post by rsync »

pizza234 wrote: post #59
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'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'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, I do a 1.5 hour heavy leg workout which includes squats, deadlifts and other assorted "big" movements with weight that is significant, compared to my body weight. No issues at all. I wouldn't do this on a 24 hour fast, but it is my regular habit to do this workout while in a 16-18 hour fasted state and in general I have very slightly better results than if I had eaten recently. Again, the issue is the amount of blood flow (and other resources) your body is putting into digestion.

Finally, while it is easy and enjoyable to do my BJJ workouts in a fasted state, I cannot, then, do several rounds of sparring at the end without more recent calories. Or rather, I can but I after round one or two I am running out of gas.

YMMV. You should just try it. It costs nothing.

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

#65

Post by [deleted] »

SwellJoe wrote: post #12
tempsy wrote: post #4

I was heading to the gym near the Twitter HQ in SF yesterday and saw Jack Dorsey walk past. He looked extremely thin and borderline sick to me. I think he does more extended fasts over the weekend but it’s a bit unnerving when someone in a position to influence behavior like he is seems to be taking fasting to an extreme.

I've seen a lot of people say stuff like this, but it's kinda gross. If you want to criticize things someone has said about their diet and health practices, that's fine (and hopefully, you'll cite sources for why they're wrong), but if you're going to make it about how they look, and make your own diagnosis about their health, that's not really OK. You don't know anything about the guy's health. He may actually be si…

[deleted]

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

#66

Post by jobigoud »

getpost wrote: post #53
najarvg wrote: post #36

Earlier quoted context omitted.

Yes it does. See - https://news.ycombinator.com/item?id=20813736

>..."might increase the risk of gallstone disease"... I do 18:6 intermittent fasting and I did have a gallstone episode. My intuition is that fasting precipitated the expulsion of stones that had formed prior to the onset of my fasting regimen. Also, while practicing intermittent fasting, I think I have a tendency to overeat during my main meal of the day, maybe as a subconscious attempt to avoid feeling hungry later…

> To avoid overeating, I need to be mindful to stop eating while I still feel slightly hungry

For me the trick is to eat really slowly, even if I'm hungry.

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

#67

Post by pmart123 »

dvt wrote: post #46
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 did for a few months this year, but I've been lazy over the summer. I'm 155lb, 6'0, so fairly skinny, maybe at around ~15% BF. I noticed that fasting doesn't help with BF at all unless I eat very clean and lift. I was at 170lb, around ~28% BF earlier this year and had to work my ass off to get my body fat percentage down.

Interesting. I just started experimenting with a 16-8 fast, and I have noticed that it is hard to eat larger portions when you constrain the eating window to eight hours. Did you think it helped maintain your 15% BF?

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

#68

Post by rsync »

frank_nitti wrote: post #52
rtkwe wrote: post #47

Earlier quoted context omitted.

A lot of diets, especially IF style diets, are pretty much just tricks to get you to eat less calorie wise. Intermittent fasting does this by just setting the simple rule, only eat during a relatively small window of time. It's easier to eat less during that period because there's only so much you can comfortably eat in that time. (Granted you can totally fit a whole day's intake in the IF period but it's harder).

Is there really no difference between eating 1500 calories at once vs. over the course of 5 meals? Of course, there is no weight loss without a calorie deficit, but are all calorie deficits equivalent on magnitude alone? I struggle with the notion that the timing does not matter at all, and much of the suggested benefits of controlling the timing focus on other metrics beside immediate weight loss. The "wisdom" of th…

"Is there really no difference between eating 1500 calories at once vs. over the course of 5 meals?"

Digestion - and the ramping up of your entire metabolic process - is not a minor task. It is an all-hands-on-deck marshaling of a number of bodily processes that preclude other processes that you might like your body to engage in.

If you are firing up this mechanism every three hours - insulin response, spiking your blood sugar, moving your stomach and bowels, etc., then you never give your body time to do any other housekeeping tasks.

Think of food intake as an interrupt, in computer science parlance. What happens to process performance when you're throwing interrupts ?

IANAD.

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

#69

Post by heymijo »

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.

There is a recent US Military study that shows that under a severe caloric deficit and with increased energy expenditure that yes, you still preserve lean body mass. [0] Granted this was not fasting, but it's interesting nonetheless.

Don't be thrown off by the title. Yes, one group received testosterone, but even the placebo group that did not receive anabolic steroids, lost nearly 10 pounds of fat without losing any appreciable amount of lean body mass.

Dr. Peter Attia wrote about it in his newsletter this past week. [1]

Between my anecdotal experience of not feeling like I lose much lean body mass while fasting, this study above, and recent evidence from studies shown that "muscle memory", where a muscle can quickly regain any lost size it has had, is in fact real...I don't lose much sleep over losing muscle while fasting.

[0] https://www.sciencedirect.com/science/article/pii/S235239641... [1] https://peterattiamd.com/can-you-preserve-lean-body-mass-dur...

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

#70

Post by CamperBob2 »

rsync wrote: post #64
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'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?)

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