Fasting | How Fasting Affects Insulin | Peripheral Insulin Resistance- Thomas DeLauer

Fasting | How Fasting Affects Insulin | Peripheral Insulin Resistance- Thomas DeLauer

Study - Journal of Clinical Endocrinology and Metabolism:
Glucose and glutathione (GHS) metabolism was studied after 12 and 60 hours of fasting on two occasions: with and without aspirin (6 g/d) t. 6 healthy lean men participated and, as mentioned, underwent 60 hours of fasting with or without aspirin (approximately 6 g/d). Fasting decreased insulin-mediated peripheral glucose uptake by 46% after 60 h and Aspirin did not alter this effect of 60 hours of fasting on insulin sensitivity. GSH concentration decreased during fasting, but the fractional synthetic rate of GSH was unaffected either with or without aspirin. Fasting did not affect inflammatory parameters, although aspirin increased soluble TNF receptors I and II. Researchers concluded that prolonged fasting induces profound peripheral IR - in contrast to type 2 diabetes mellitus, high-dose salicylate does not affect fasting-induced peripheral IR.

Why Does this Occur?
Generally, prolonged fasting (greater than 48 hours) in humans is accompanied by a reduction in insulin sensitivity, elevated plasma FFA levels, elevated intramuscular fat levels, but also an increase in whole-body fat oxidative capacity. Furthermore, prolonged fasting-induced insulin resistance is not accompanied by hyperglycemia or hyperinsulinemia, factors that have been suggested to cause mitochondrial dysfunction in diabetes. It could therefore be anticipated that despite the development of insulin resistance, mitochondrial function is maintained to accommodate increased fat oxidation during prolonged fasting. Conversely, if (lipid-induced) insulin resistance or factors associated with the insulin-resistant state do cause mitochondrial dysfunction, it’s believed a reduction in mitochondrial function with prolonged fasting would occur. Prolonged fasting, however, is a physiologic condition in which insulin resistance develops to spare glucose for utilization by the brain, and increased FFA levels are accompanied by increased fat oxidation. Prolonged fasting-induced lipid accumulation and insulin resistance are considered to be a functional physiologic response. As mentioned, reduced insulin sensitivity saves carbs for the central nervous system, being obligate for glucose and not requiring insulin for its uptake, whereas increased lipid availability at the same time can serve as a direct available energy source for the muscles and is paralleled by an enhanced fat oxidative capacity.

FFA & Mitochondria:
Elevated plasma free fatty acids induce insulin resistance through activation of Jun NH(2)-terminal kinase and nuclear factor-kappaB inhibitor kappaB kinase, which leads to hyperphosphorylation of the insulin receptor substrate type 1 (IRS1).

Study – Diabetes:
In this study, FFA levels were increased approximately ninefold after 60 hours of fasting in healthy male subjects, leading to elevated intramuscular lipid levels and decreased muscular insulin sensitivity
These findings confirm that the insulin-resistant state has negative effects on mitochondrial function. Given the low insulin and glucose levels after prolonged fasting, hyperglycemia and insulin action can be excluded as underlying mechanisms, pointing toward elevated plasma FFA and/or intramuscular fat accumulation as possible causes for the observed reduction in mitochondrial capacity. The increased exposure of skeletal muscle mitochondria to elevated levels of free fatty acids (FFA), seen in insulin resistance and type 2 diabetes, has been suggested to interfere with proper mitochondrial function. The acute elevation of plasma FFA by lipid infusion is accompanied by down-regulation of the transcriptional co-activator peroxisome proliferator-activated receptor gamma coactivator-1α (PGC1α) and other genes involved in mitochondrial metabolism.

References:

[TabithaEnglish]

I’m on day 5 of fasting and my glucose has gone from 63 to 94. I’m glad I found this video!

[tripptank]

Thomas is a genius; He know's we'll have to watch most of his videos more than once if we want to catch everything. Professional YouTuber right here.

[BeeCrashful]

Great timing !
I planned to do a 3-4 days fast and this video encourages me to do so :)
And if someone dare say it's not healthy... i have all the arguments needed now !

Thanks Thomas !

[judybanks]

So interesting! I'm 3 days into a prolonged fast (fat adapted). I noticed my glucose rose to 66 and keytones dropped to 3.2 after a 5 mile afternoon walk. By the evening, my glucose dropped to 49 and keytones rose to 5.5. The body is so incredibly flexible! Loving the content you put out there. My vote is to keep it "technical".

[ZachSilverberg]

As a type 1 diabetic myself, I found this very helpful. The longest fast I have been able to do is 57 hours. This gave me some ideas. Thank you Thomas for sharing you knowledge!

[Reaperaxe]

Thomas, your videos have been on absolute point lately. Please keep showing people the science and justification of efficient nutrition and growth!

[bomerboy]

hi there your awesome im in canada just found out i got dibetes im watching lots of your video im cuting out carbs and doing this keto stuff your talking about i love it its been a week i lost 11lbs feel great keep in mine im a big guy weigh like 330 lbs i got a long way to go but im learning everyday with your help thanks alot and im 50 years old next week again your great ill be watching thanks thomas

[vesperal]

I think this is your best video. You should do one with Dr. Jason Fung on the material shown here.

[Biohackthefat]

I get my clients into extended fasting after 11 weeks of working with me and it always Amazes them when they take their fasting blood sugar and ketone tests. We calculate out the GKI and then compare to the GKI when they were Intermittent Fasting and the difference is amazing to see. It isn’t uncommon for the body to produce more glucose from the glycerol backbone of the fat molecule. I’ve also experienced this for myself Thomas. As at times throughout a fast my glucose will be elevated beyond what Is was throughout my Intermittent Fasting protocol. Good video here! Thanks for sharing!

[bighurt]

I needed to hear this. I broke my fast and when I check my blood about an hour later and it had spiked to 144. Then few hours later it dropped to 78. Away I needed to hear this, thanks!!

[falconstrokeflyer]

This answers the conundrum I’ve been experiencing. Type 2 diabetic, three weeks in Keto, IF 16-8, and trying to reduce meds. Glucose levels actually rising to concerning levels during fasting and very minimal carb intake. Working out 5 days a week, I’ve lost 20 lbs in three weeks. Feel great, but I’m wondering if my next A1C will be better or reflect these elevated glucose levels.

[DDooMRooMM]

Brother, you are amazing with this stuff. Im breaking a 48 hr fast later today then I'm starting a 60 hour fast Monday. Thank you so much for the time you dedicate to us. Love you!

[naturalnia]

Great video! I just completed an 85 hour fast was very concerned about why my blood sugar rose so high after refeeding. I read a scientific article that explained and then watched your video, which elaborated and broke down the information perfectly. It all makes sense now. Thank you!

[musicboy]

Wow, a great deal of fascinating and useful information! I’m type 2 using IF and weight training to help control blood glucose for going on four years now. It’s working and, at 65, I’m becoming a better version of myself. My resolution for 2019 is to do more 3-5 day fasts (did two last Fall) and this video, along with your vids on dry fasting, are a real inspiration. God bless you, Thomas!

[sourinmaiti]

Hey Thomas, you are doing an awesome job. Can you put more videos on same topic? Elevated morning blood sugars during fasting is scary. If not explained properly, people will get scared and run away from keto and fasting. I do 20- 4hour(eating) fasting every day and see 115 avg blood sugars every morning 8am. That comes down by lunch. Appreciate your awesome work here.

[juliamontalvo]

Thomas thank you for this video. It means a lot to me. I'm currently fasting for weight loss and to get rid of my diabetes for good.

[lindatsl]

I started low carb and intermittent fasting in May this year (2021). By late June and early July I managed to get my FBG to the 5s. Then suddenly starting 1st week of August my FBG spikes up to high 6s and low 7s. I was depressed and wondered what have gone wrong. Thank God I found this video. Am going to continue with occasional fasting and go low carb as a lifestyle change. Blood pressure stayed below 120/80 though

[HatefulXP]

The mitochondria is the powercell of the house.

[lemonginger]

most underrated channel !! Respect for you !!

[briancrane]

Tom you are strong, fit AND SMART! A rare combination. Really enjoy your vids! Thanks!