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Intermittent and extended fasting

Toshi

Harbinger of Doom
Oct 23, 2001
27,584
2,220
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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
27,584
2,220
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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
10,173
6,191
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
27,584
2,220
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
27,584
2,220
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
27,584
2,220
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!