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Intermittent and extended fasting

Toshi

Harbinger of Doom
Oct 23, 2001
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I had a strong cup of coffee about an hour before these watch screenshots. It was adulterated with some MCT oil.

Note distinct lack of heart rate elevation at and after that time, and the odd transient hypoglycemic dip! I was right around 24 hours into a fast at that time, thus the very steady, low glucose prior to the coffee ingestion.
 

Toshi

Harbinger of Doom
Oct 23, 2001
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CGM data potentially of interest to fellow nerds.

Context is that these data are from yesterday. I didn't eat yesterday--ate at ~2000, so 4 hours before the x-axis begins.

The variability while I slept was probably the dawn phenomenon.

The small, brief spike from 85-90 mg/dL to 112 or so is exercise-induced hyperglycemia, which in turn was provoked because I (intentionally) did part of my workout in a glycolytic rather than beta oxidation range of effort. Again, I fasted all day so this infusion of glucose was via hepatic gluconeogenesis, I believe.

Here's a case report of a woman with a tremendous exercise-induced hyperglycemic spike, noting 11 mmol/l glucose == 198 mg/dL!


And here is Peter Attia demonstrating a similar post-workout mild spike as in my data:


(This shows the benefit of CGM as it would have been trivial to completely miss the short ~112 mg/dL peak in my data.)
 

canadmos

Cake Tease
May 29, 2011
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Canaderp
Was watching some stuff from the former FPSRussia YouTube guy about his brief period in prison. He tried fasting while in there and said it was awesome for him, just a bit of a mind hurdle to get over at first.
 

Kevin

Turbo Monkey
Ive been pretty consistent with my 11h (#madlad) eating window.
Still havent lost any weight though so I guess 11 might not be enough.

I drink a cup of coffee when I wake up around 6ish, and then another at 7 And breakfast at 9.
Those cups of coffee shouldnt mess up my “fasting” window should they? @Toshi
 

Toshi

Harbinger of Doom
Oct 23, 2001
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They shouldn’t mess with it, no, as long as no sugar. Cream or MCT oil in it likely is ok as well.

Exactly how long is sufficient or optimal is very much an open question. 13 hrs min? Maybe dependent on one’s metabolism and diet composition?
 

Kevin

Turbo Monkey
Yeah I figure Im somewhere in the region of effectiveness but who knows. At least its stopping me from stuffing my face for half a day even if its just that.

Im not even overweight, just trying to get rid of the last couple of kilo’s that are kinda bugging me.
Maybe Ill just try to eat a bit extra during the day and stop eating after dinner and drink more tea or something.
 

Toshi

Harbinger of Doom
Oct 23, 2001
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Since putting in a new sensor on Sunday my glucose readings via the Dexcom have been alarmingly high. No spikes but often sitting between 110-135 mg/dL! I don't trust my wife's Accu-Chek and am out of test strips for that anyway...

... but then I remembered that I'm a physician, so I ordered myself a basic metabolic panel from our hospital's outpatient lab and popped up for 10 minutes to get it drawn.

At the time of that draw the Dexcom was reading 124 mg/dL. The lab's result: 88 mg/dL. Yeah, 36 mg/dL off. I calibrated the Dexcom, needless to say, but that's disappointing for a "calibrated from the factory" unit--that's its draw in part.
 
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Toshi

Harbinger of Doom
Oct 23, 2001
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The flip side of getting this unplanned basic metabolic panel is that I also threw in an order to check a random fasting insulin level with that same draw. This shows my insulin resistance from a pre-August SAD to be nicely resolving.



HOMA2-IR of 1.16, 110.8% beta cell function.

For context, normal insulin sensitivity is 1.0 or less, 1.4 or less is "a normal HOMA[2]-IR value for a healthy person", "above 1.9 indicates early insulin resistance", and "above 2.9 indicates significant insulin resistance." So I'm getting there!
 

Sandwich

Pig my fish!
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Well after a year of this nonsense I'm down 28.8 lb. I didn't hit my goal of 30lb and I'm right on the borderline of normal/overweight BMI, but I've lost my man-tits and am down to really one chin, maybe a chin and a half. While fasting, I'm much less sensitive to hunger, and electrolyte pills seem to help with migraines and actually seem to help with hunger as well. Unfortunately I seem to have plateaued, but that's not much of a shocker with my surgery, followed by thanksgiving and holidays, and my takeup of spinning is probably prohibiting a bit of pure weight loss.

Brief n=1 commentary on exercise while fasted: definitely less pep in my step compared to fed exercise. I also seem to sweat later (takes me longer to warm up?). Not much insight on weight loss or anything. I wish I didn't have to exercise in the morning, as the fear of muscle breakdown rather than fat catabolism is scerry.
 

Toshi

Harbinger of Doom
Oct 23, 2001
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Re pep in step while fasted (thus fat oxidation) exercise, that’s eminently trainable, to the point that one can have significant fat oxidation capability even at 70% of max effort:


Cliffs Notes (see his linked Fat Oxidation: A Case Study post from this one, too) are that logging a bunch of zone 2 hours are the key.
 

Brian HCM#1

MMMMMMMMM BEER!!!!!!!!!!
Sep 7, 2001
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Ive been pretty consistent with my 11h (#madlad) eating window.
Still havent lost any weight though so I guess 11 might not be enough.

I drink a cup of coffee when I wake up around 6ish, and then another at 7 And breakfast at 9.
Those cups of coffee shouldnt mess up my “fasting” window should they? @Toshi
Black coffee/tea, yes. Just don't add any sweeteners or milk/cream will trigger insulin production. I wont even chew gum, use mints during the fasting period because of the sweeteners as small as it seems it still takes you out of your fast. Intermittent fasting diets, you lose your weight much slower than a crash diet. I can average about 1-1.5 lbs of lose a week. Keep high protein low carb will also help lose faster. I do a 16h fast monday-friday and high protein very low carbs sat & sun, only drinking alcohol Friday & Saturday nights.
 
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canadmos

Cake Tease
May 29, 2011
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Canaderp
Black coffee/tea, yes. Just don't add any sweeteners or milk/cream will trigger insulin production. I wont even chew gum, use mints during the fasting period because of the sweeteners as small as it seems it still takes you out of your fast. Intermittent fasting diets, you lose your weight much slower than a crash diet. I can average about 1-1.5 lbs of lose a week. Keep high protein low carb will also help lose faster. I do a 16h fast monday-friday and high protein very low carbs sat & sun, only drinking alcohol Friday & Saturday nights.
This is the program I'm subscribing to.

@Toshi I went to go finish reading the book I purchased per your suggestion. It straight up got up and walked away and into the hands of a coworker of teh lady friend. Damnit.
 

Toshi

Harbinger of Doom
Oct 23, 2001
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3 hours and 9 minutes after a 75 g oral glucose tolerance test. (With insulin levels at 0, 1, and 2 hours! once the lab reports them.)

Note the oscillations, shooting up, correcting down, repeating thrice over these three hours. And as a result, likely due to the periods of reactive hypoglycemia, I feel hungry now.

This is a nice illustration of why snacking on carbs is counterproductive, as it’ll lead to attenuated versions of this response. 75 g carbs given as a super fast absorbing drink is about the worst example, of course.
 

Toshi

Harbinger of Doom
Oct 23, 2001
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I’m going to eat tomorrow morning at around 60 hours. Skied a full day and bike commutes twice while fasted.
 

Toshi

Harbinger of Doom
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A highlight from recent lab tests. I have high TC, LDL-C, HDL-C, HDL-P, and LDL-P. Eating lots of meat apparently does this, go figure.

But the LDL particles are large (which is a good pattern), and the overall pattern of the cholesterol size distribution is in keeping with insulin sensitivity: 25th percentile on their scale for their proprietary LP-IR metric, lower bring more insulin sensitive.

Interestingly the absolute insulin values for my pseudo-Kraft test I also did were high, albeit with the peak insulin value at 1 hr, which is the normal shape of that curve. This may reflect non-standardization of insulin assays since the other evidence is not of insulin resistance now.
 

Brian HCM#1

MMMMMMMMM BEER!!!!!!!!!!
Sep 7, 2001
31,670
114
Bay Area, California
View attachment 141090


A highlight from recent lab tests. I have high TC, LDL-C, HDL-C, HDL-P, and LDL-P. Eating lots of meat apparently does this, go figure.

But the LDL particles are large (which is a good pattern), and the overall pattern of the cholesterol size distribution is in keeping with insulin sensitivity: 25th percentile on their scale for their proprietary LP-IR metric, lower bring more insulin sensitive.

Interestingly the absolute insulin values for my pseudo-Kraft test I also did were high, albeit with the peak insulin value at 1 hr, which is the normal shape of that curve. This may reflect non-standardization of insulin assays since the other evidence is not of insulin resistance now.
Do you think the LDL-P is associated to eating a lot of red meat, or just meat in general? All the other levels look good. I think.
 

Toshi

Harbinger of Doom
Oct 23, 2001
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Do you think the LDL-P is associated to eating a lot of red meat, or just meat in general? All the other levels look good. I think.
Don't know, and not planning on experimenting with no red meat.

Note that it's my small LDL-P that's pictured there, between 50th and 75th percentile. My total LDL-P is off the charts high for their norms (although probably pretty in line with others eating largely carnivore). The small LDL-P appears to matter more than the total, but in the context of low glucose, low insulin, high HDL-C and -P, and low triglycerides I'm making the bet that it doesn't matter that much.
 

Brian HCM#1

MMMMMMMMM BEER!!!!!!!!!!
Sep 7, 2001
31,670
114
Bay Area, California
Don't know, and not planning on experimenting with no red meat.

Note that it's my small LDL-P that's pictured there, between 50th and 75th percentile. My total LDL-P is off the charts high for their norms (although probably pretty in line with others eating largely carnivore). The small LDL-P appears to matter more than the total, but in the context of low glucose, low insulin, high HDL-C and -P, and low triglycerides I'm making the bet that it doesn't matter that much.
Yeah, I would never go that drastic and cut out red meat, ever! I checked out the site you get your meat from, and the cuts look friggin amazing! Are they as good as they look, and worth the purchase?
 

Toshi

Harbinger of Doom
Oct 23, 2001
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Yeah, I would never go that drastic and cut out red meat, ever! I checked out the site you get your meat from, and the cuts look friggin amazing! Are they as good as they look, and worth the purchase?
They are as amazing as they look. I am ruined now for anything else. I guess I'll have to keep working for a few years yet. :D
 

Brian HCM#1

MMMMMMMMM BEER!!!!!!!!!!
Sep 7, 2001
31,670
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Bay Area, California
They are as amazing as they look. I am ruined now for anything else. I guess I'll have to keep working for a few years yet. :D
Yeah, that's the problem. You set the standards too high and nothing else compares. Wonder if there is a big difference in taste and/or texture between American to Japanese wagyu. I'm sure they both kick serious ass!
 

Toshi

Harbinger of Doom
Oct 23, 2001
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Yeah, that's the problem. You set the standards too high and nothing else compares. Wonder if there is a big difference in taste and/or texture between American to Japanese wagyu. I'm sure they both kick serious ass!
The ones from Snake River Farms are wagyu hybrid, so half-Japanese like me. Half wagyu, half Angus lineage. They are just right in terms of being meat still, IMO, and not gelatinous carriers of beef fat.
 

Toshi

Harbinger of Doom
Oct 23, 2001
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38 hours into a fast at the moment. One of my med school buddies was going to do a 120 hour fast and I was going to tag along in solidarity. But then she called it at 49 hours because she wanted to eat some leftovers before they went bad (fair enough).

I shall extend this one for as long as I feel fine.
 

Toshi

Harbinger of Doom
Oct 23, 2001
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I think I will break my fast tomorrow morning, circa 60.5 hrs. Kind of lightheaded while practicing trumpet and never got the day 2 rush, even with ample caffeine on board.
 

Brian HCM#1

MMMMMMMMM BEER!!!!!!!!!!
Sep 7, 2001
31,670
114
Bay Area, California
I think I will break my fast tomorrow morning, circa 60.5 hrs. Kind of lightheaded while practicing trumpet and never got the day 2 rush, even with ample caffeine on board.
That's a crazy long fast, are you losing weight and has it made an impact with your insulin levels? The longest I've gone is about 20 hrs. I've been meaning to go get a fasting blood test to see if this diet is getting me out of that pre-diabetes mode. I've been back on the IFD since mid Jan, I want to give it another 2-3 weeks before the test. Been in the gym 6-7 days a week lifting weights for 1-1.5 hrs and taking 24g of protein powder and 5mg of creatine everyday right after.
 

Toshi

Harbinger of Doom
Oct 23, 2001
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That's a crazy long fast, are you losing weight and has it made an impact with your insulin levels? The longest I've gone is about 20 hrs. I've been meaning to go get a fasting blood test to see if this diet is getting me out of that pre-diabetes mode. I've been back on the IFD since mid Jan, I want to give it another 2-3 weeks before the test. Been in the gym 6-7 days a week lifting weights for 1-1.5 hrs and taking 24g of protein powder and 5mg of creatine everyday right after.
Yeah, pretty much stalled since Jan 1 but lost 40 lbs up until that point.

Never checked it before doing this but my fasting insulin levels are good. Last HOMA2-IR calculated to be something like 1.2 iirc (so acceptable) and my LP-IR from a NMR LipoProfile cholesterol + particle panel was 25th percentile, lower being more insulin sensitive.
 

Brian HCM#1

MMMMMMMMM BEER!!!!!!!!!!
Sep 7, 2001
31,670
114
Bay Area, California
Yeah, pretty much stalled since Jan 1 but lost 40 lbs up until that point.

Never checked it before doing this but my fasting insulin levels are good. Last HOMA2-IR calculated to be something like 1.2 iirc (so acceptable) and my LP-IR from a NMR LipoProfile cholesterol + particle panel was 25th percentile, lower being more insulin sensitive.
40 lbs is awesome! You still want to lose more, or just maintain where you're at?
 

Toshi

Harbinger of Doom
Oct 23, 2001
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Thats the beauty of that diet, other than your fasting period you can kinda eat whatever you want, in moderation of course.
I don’t stay keto when eating but I moderate carbs and am pretty good to avoid vegetable oils. I want my ingested fats to be omega-3 somewhat but mostly saturated.
 

Brian HCM#1

MMMMMMMMM BEER!!!!!!!!!!
Sep 7, 2001
31,670
114
Bay Area, California
I don’t stay keto when eating but I moderate carbs and am pretty good to avoid vegetable oils. I want my ingested fats to be omega-3 somewhat but mostly saturated.
Weekdays I stay fairly strict, same with omega-3, good fats tuna, salmon and I like snacking on raw almonds and avocados. Friday & Saturday nights all bets are off, french fries, tortilla chips, ice cream and alcohol etc. Wife was out of town last weekend, went out with a buddy to our local steak house for a blackened ribeye with blue cheese compound butter, onion strings & cabernet demi-glaze with a baked potato & brussels sprouts. Mixed with multiple cocktails and beers after at the local sports bar. So friggen good! Good food kicks ass!
 

Sandwich

Pig my fish!
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May 23, 2002
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I'm taking a brief hiatus from fasting after hitting a plateau hard at the start of this year. I've lost about 29.2 lbs, my goal was 30, but fuck I can't seem to lose another 8 tenths. I've actually gained 5 lbs in like two weeks without changing my diet, fasting or eating habits, so I think something is going on with my digestion and I need to normalize for a bit. Maybe a couple weeks off then back on the diet, as it has seemed to work very well for me for a variety of reasons...