Author Topic: Intermittent Fasting  (Read 13371 times)

Offline Chris Salvato

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Re: Intermittent Fasting
« Reply #20 on: December 25, 2008, 09:59:22 PM »
Did not read this whole thread, sorry...

Its more than just a "break" for your digestive system.  It lets your body sort all of its nutrients out thoroughly.  Muscles get replenished glycogen, liver may go into a glycogen deficit -- insulin sensitivity is modulated favorably and increases in pulsatile GH is shown.

All more advanced questions have probably been answered on PMenu -- so you can search the link that steve posted.

Offline tombb

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Re: Intermittent Fasting
« Reply #21 on: December 26, 2008, 09:23:18 AM »
Muscles get replenished glycogen, liver may go into a glycogen deficit

I am sure this is what Chris meant, but just to clarify, you -don't- have muscles replenish in glycogen AND liver go into glycogen deficit.

Rather, both muscles and liver go into glycogen deficit, as they convert it into glucose (mostly to sustain your brain which will not work on fat energy). Eventually you might even create some glucose from other substrates like proteins (gluconeogenesis), but never so much to stimulate insulin-induced glycogenesis in the absence of nutrients.

After you resume eating, a healthy insulin response replenishes both liver and muscles with newly synthesized glycogen.

Offline Chris Salvato

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Re: Intermittent Fasting
« Reply #22 on: December 26, 2008, 01:27:40 PM »
was kind of rushed, but yeh...

muscles and liver start using glycogen.  In order of priority, these tissues get the mobilized glycogen (among others, but I am being simplest):
1) Brain
2) Muscles
3) Liver

In short, the lack of food allows your body to hit a "steady state", in theory.  This is where you see a lot of the benefits come about as opposed to just some "time off" for your intestines. GI Tract and digestive system capillary beds.

Offline Alec Furtado

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Re: Intermittent Fasting
« Reply #23 on: December 26, 2008, 03:47:54 PM »
[...]

Your body has a perfectly fine source of energy: fat cells. You don't need to give it fuel, it's already there. By constantly eating, you actually promote fat storage, not its use. [...]

I've always been told that your body will go after your muscle before fat if it needs energy.
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Offline Bret [Soundcrafter]

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Re: Intermittent Fasting
« Reply #24 on: December 26, 2008, 04:28:18 PM »

I've always been told that your body will go after your muscle before fat if it needs energy.

I'd read this too, as a reason why "missing a meal is worse than eating poorly." Thoughts?

Offline tombb

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Re: Intermittent Fasting
« Reply #25 on: December 26, 2008, 04:38:56 PM »
[...]

Your body has a perfectly fine source of energy: fat cells. You don't need to give it fuel, it's already there. By constantly eating, you actually promote fat storage, not its use. [...]

I've always been told that your body will go after your muscle before fat if it needs energy.
It usually uses both fat and proteins at the same time if you are really short of energy.
Exercise and hormones (and other chemicals) however modulate the proportion between these various energy pathways.

Basically your body tries to figure out which situation you are in. If you were stuck at the bottom of a well (no exercise and no food), your best hope for survival would be for your body to remove excess energy consumption (dismantle muscle for energy), reduce your metabolism, and keep fat as long as possible to keep you alive and insulated longer with the smallest energy cost until you are free again.
If instead you were the predator trying to chase after the prey without ever catching it (exercise but not much food), then your best hope for survival would be to invest in muscle even at the cost of some fat, and actually increase your metabolism so you can actually catch your prey and get some food.

But yes essentially if you reduce calories for long periods or do longer fasting you are always going to end up with less muscle mass than if you just ate the whole time, but if you do it in a well timed and well thought-out way you can lose a lot of excess fat and still end up with more muscle than when you started.
Bodybuilders often use two phases, one with high calories for building as much mass as possible, and one with reduced calories a few months before a competition to reduce bodyfat. During this phase they exercise but their goal is mostly to try to maintain their gains despite the lower calories, rather than trying to increase them further.

Offline Chris Salvato

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Re: Intermittent Fasting
« Reply #26 on: December 26, 2008, 05:11:37 PM »
The body was actually not meant to eat 6 times a day....when you think about it from an evolutionary standpoint, 6 meals a day consistently makes almost no sense.

Our bodies can go for a pretty decently long time...like a day or two...before you can enter this "starvation mode"

Offline Alec Furtado

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Re: Intermittent Fasting
« Reply #27 on: December 26, 2008, 05:17:38 PM »
K cool. This sounds like something to try, although I don't think I would do well since I'm surrounded by crap (candy, cookies... it's the holidays of course) and would probably end up sneaking some... I'm thinking I'll go for it in college when I have full control over what I eat. I eat well now anyway so no worries until then.
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Offline Chris Salvato

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Re: Intermittent Fasting
« Reply #28 on: December 26, 2008, 05:20:31 PM »
if you are surrounded by crap, fasting may actually be worth a try.  If you are disciplined and say, "I am not eating until 3 PM" then the crap is actually not too hard to resist -- and when u do eat you kind of make sure you eat good food not crap.  I would suggest trying it first before saying its too hard.  If it doesn't work, try it again later.

Offline Steve Low

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Re: Intermittent Fasting
« Reply #29 on: December 26, 2008, 05:25:45 PM »
If you ARE eating crap though..... IFOC -- IF on crap -- doesn't work. May actually work worse than eating your 6 meals a day from the experiences I've seen.
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Offline Dan Frank

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Re: Intermittent Fasting
« Reply #30 on: December 26, 2008, 06:12:54 PM »
Wow. I'd like to know how you guys know so much about all of this.  :o

But anyway, I'm totally inspired to have more self-control. I'm definitely going to do some fasts sometime soon (believe me, I'll get a date down asap; I know what happens when I don't do things immediately.)
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Offline Bret [Soundcrafter]

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Re: Intermittent Fasting
« Reply #31 on: December 26, 2008, 06:52:55 PM »
A couple points from a study

Quote
Risk factors for type 2 diabetes were measured in each of the 3 published human studies of ADF (36-38; Table 2Go). Evidence from these trials suggests that ADF [Alternate-Day Fasting] does not alter fasting concentrations of glucose but may beneficially modulate other indexes of diabetes risk, such as insulin sensitivity. Specifically, Halberg et al (38) observed that, when normal-weight persons fasted for 20-h periods (fast day) and then ate their habitual diet ad libitum on alternate days (feast day), the insulin-mediated glucose uptake increased after 2 wk of intervention, as measured by using the euglycemic-hyperinsulinemic clamp technique. These results are supported by a study conducted by Heilbronn et al (36), which found that, after 3 wk of ADF, insulin response to a test meal was reduced, which implied improved insulin sensitivity. It is interesting that this effect on insulin sensitivity occurred only in male subjects (36).

Reaffirming that males benefit more from IF.

Quote
On the other hand, overall fat oxidation was shown to increase by an average of 15 g/d over the course of the trial, according to indirect calorimetry. The authors also observed a positive correlation between fat oxidation and weight loss, which suggested that those subjects with a greater ability to oxidize fat may have lost more weight (37). Thus, whether the weight loss noted is a result of ADF may depend on a person's ability to oxidize fat.

So here, the benefits are pointed out, but only the extent of them varies from person to person.

Offline Alec Furtado

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Re: Intermittent Fasting
« Reply #32 on: December 26, 2008, 07:04:50 PM »
Those phrases are too esoteric for me. :-\

if you are surrounded by crap, fasting may actually be worth a try.  If you are disciplined and say, "I am not eating until 3 PM" then the crap is actually not too hard to resist -- and when u do eat you kind of make sure you eat good food not crap.  I would suggest trying it first before saying its too hard.  If it doesn't work, try it again later.
Yea... I found what really helps actually is just to keep my water bottle with me. I think I just like to have something no matter what it is. 'Course then I gotta take a piss every 10 minutes but I'd say it's still better :D

I'm wondrin' if that "oral fixation" is because I used to chew gum 24/7 (Stride FTW!) and I ran out and was too lazy to get more. Even though I ran out like... months ago... :P


Now just expanding a bit, what are the "safe" ages for stuff like this? I know religions that call for fasting that don't say people under and over a certain age should participate.
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Offline Bret [Soundcrafter]

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Re: Intermittent Fasting
« Reply #33 on: December 26, 2008, 07:18:04 PM »
Alec:The first statement just says that men are better than women.

KIDDING.

It basically just reinforces what Chris said about insulin sensitivity.

The second suggests that IF assists weight loss.

Offline Alec Furtado

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Re: Intermittent Fasting
« Reply #34 on: December 26, 2008, 07:26:43 PM »
Augh sorry lol and the insulin sensitivity is what again? I'm gonna guess that it's good but what happens? You're more sensitive so your body makes less when you need it so any spikes will be lower? = less sluggishness & = less to be converted to fat?


If whatever I just brainstormed is true... how would you know that your body will make less instead of making the same amount and totally getting owned by insulin since it's kind of less tolerant...
« Last Edit: December 26, 2008, 07:28:28 PM by Alec Furtado »
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Offline Bret [Soundcrafter]

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Re: Intermittent Fasting
« Reply #35 on: December 26, 2008, 07:34:01 PM »
I can't entirely answer that.

Higher sensitivity = less to get the same effect, so yes, relatively 'high' insulin levels would be lower overall, I believe.

Offline tombb

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Re: Intermittent Fasting
« Reply #36 on: December 26, 2008, 07:42:01 PM »
Augh sorry lol and the insulin sensitivity is what again? I'm gonna guess that it's good but what happens? You're more sensitive so your body makes less when you need it so any spikes will be lower? = less sluggishness & = less to be converted to fat?


If whatever I just brainstormed is true... how would you know that your body will make less instead of making the same amount and totally getting owned by insulin since it's kind of less tolerant...
Not exactly Alec.
Insulin Sensitivity is good because poor diet and lack of exercise cause the opposite effect, insulin resistance, which means basically you have a weaker response to normal levels of insulin and stop getting all the good effects of insulin. From there you can have fat molecules released into your bloodstream, elevated glucose, and your muscles don't get replentished with energy as efficiently as when they were responsive to insulin and you basically go toward type2 diabetes (all bad things).

Remember, Insulin is a very good anabolic hormone. Every time you need to have nutrients like aminoacids/protein and/or energy shuttled into your muscle, insulin helps you do that. It also keeps you energetic and healthy.
You never feel sluggish because of insulin itself, you feel sluggish because things (including insulin levels) are out of balance.

Offline Chris Salvato

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Re: Intermittent Fasting
« Reply #37 on: December 26, 2008, 07:46:58 PM »
Insulin is like money -- not the root of all evil -- its good that you have it when you need it -- but too much of it constantly flowing just leads to trouble...especially when you "run out" (for lack of a better analogy) and become diabetic.

If you are insulin sensitive you are actually more prone to crashing in today's societies because anything that is starchy/sugary will cause your blood sugar to rocket up a ton higher than it is used to causing a massive spike in insulin which lowers blood sugar causing your brain to be like "wtf is going on here" -- but that just means the foods most of us consume in today's society are the problem (pastas, breads, etc).



Offline Alissa J. Bratz

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Re: Intermittent Fasting
« Reply #38 on: December 26, 2008, 07:52:07 PM »
Okay, I skimmed this, but I'm very glad it's here because tomorrow when I'm back in my routine and fresh I want to read it through carefully. I have wondered for a very long time how to fast appropriately but haven't really taken the time to do the research. Part of this is because I'm scared to try fasting. As a recovered anorexic/bulimic this stuff seems awfully scary to me.

Some days I find that I "fast" naturally simply by being too busy or too preoccupied to eat, and there are no adverse effects until suddenly I get this huge surge of hunger and I either go into a hypoglycemic state or I go straight for the crap. However this is usually because (I'm guessing) I'm already in a stressed period of my life (which is making me forget to eat anyhow) and have already been on a crap diet for a while. Life stress and crap diet usually go hand in hand for me. :P Arguably the hypoglycemic state is better because I have a system for dealing with that which involves consumption of juice or fruit followed by a protein source (usually yogurt or cheese) until I feel balanced again. This assumes, of course, that I catch myself at a point before the very thought of food makes me queasy. (Seems like a design flaw to me: when blood sugar gets so low that someone is dizzy, let's make food seem icky... wth is that about???) But as this is accidental fasting it's beside the point.

I have never tried to fast thoughtfully and intentionally before, although the idea has always intrigued me. It's good to see that there are noted differences between men and women for fasting. I wonder why this is (my guess is that all that childbearing evolutionary business has to do with it), and also where I could find studies that support a sensible fasting plan/system for women.

I will have to read this thread more carefully, and do some googling to find out about fasting for women. Good info in here. Thanks guys!
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Offline Chris Salvato

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Re: Intermittent Fasting
« Reply #39 on: December 26, 2008, 08:04:22 PM »
Muse -- before you google look at these two sites:

The IF Life Resources section - Articles, Studies and Recommended Reading
http://www.theiflife.com/resources/

Performance Menu Fasting Forum - Steve posted this earlier
http://www.performancemenu.com/forum/forumdisplay.php?f=4

The forum would be a good place to ask questions on female fasting -- or do a search there.

I would think, evolutionarily, women would not be fasting as much.  Males would go out and hunt/fish and be active during the day and get the majority of meals while only being able to carry little or no food along with them for most of the day.  Women would eat and prepare food pretty regularly as a result while feeding and preparing food for the children and rest of the camp.  This would mean males would adapt more favorably to fasting whereas women would not...and there is data and experiences that support this :)