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VicodinMakesMeItchy t1_j2auzbv wrote

Reply to comment by [deleted] in Intermittent Fasting significantly reduced systolic blood pressure (SBP), but not diastolic blood pressure (DBP). The effects are likely due to weight loss. by glawgii

I suppose my “hot take” would be that after you’ve fasted for more than 12 hours, you have burned off any glucose plus all of the glycogen stored in your liver. There is no longer any form of carbohydrate to derive energy from, so the body directly mobilizes fat stored inside adipocytes. That produces ketones in the body, which have been shown to have their own beneficial effects.

Eating all day at a calorie deficit will slowly chip away at the fat, but it’s less effective because energy for the missing calories are taken from a constantly-replenished glycogen store, plus some from fat cells. Removing the glycogen store in the liver through fasting and forcing fat cells to provide all of the energy instead, means your calorie deficit is being taken directly from fat stores. Remaining in the glycogen-depleted state for a few hours per day means more fat is burned through for energy in total.

Adding in the fact that excess glycogen stored in the liver is converted into fat and stored in adipocytes, the less glycogen you have overall, the smaller the fat stores in adipocytes will be, and therefore overall weight.

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just_tweed t1_j2f49p5 wrote

Any sources for 12h? I've seen numbers like 20h, and other data suggesting it might take even a couple of days to fully switch to ketones as fuel.

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[deleted] t1_j2b6n9o wrote

[removed]

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chadwicke619 t1_j2b9ps1 wrote

You’re missing the point. You’re body doesn’t keep track of time in the same way that we do. People who fast stop eating at, say, 8PM. At that time, their body has plenty of glucose to work with, plus there is insulin present. As you get further away from your last meal, you have less and less insulin, and less glucose just floating around, and this applies to everyone. Now, most people wake up and eat, replenishing this glucose that is floating around. Not people who fast, though. They keep on going, until the body just has to start chipping away at fat. People who don’t fast never dip into this zone where they are just walking around, burning fat - they keep the store replenished. People who fast spend a few hours a day in this zone.

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T6000 t1_j2cjjww wrote

No, I'm not missing the point. Intermittent fasting is just another fad diet that people hope will put them in a caloric deficit. I'd rather eat when I feel like it and still lose weight if I chose to by eating low calorie dense food. Most people won't find sustainability in intermittent fasting or keto.

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chadwicke619 t1_j2cphzt wrote

Well, no point debating the fact. You deleted the comment that we are discussing in the first place.

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amoose-boosh t1_j2fezzj wrote

Do what works for you, what works for some doesn’t work for all. But IF is no more of a fad than the three meal a day diet which most of us follow. For most of human history meals came sporadically - it’s relatively easy to stick to because our physiology evolved to handle it. I’ve personally done IF (OMAD) and stuck with it for over a year.

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VicodinMakesMeItchy t1_j2bysat wrote

Of course your metabolism has no idea what time it is. It doesn’t matter what time it is—after 12 hours of fasting, you have burned through your glycogen stores. It’s literally just biochemistry.

Get off your bro science high horse. You clearly don’t know as much about metabolic processes as you think you do.

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