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Kind of, skipping breakfast definitely prolongs the usual nighttime fast whereas eating late definitely shortens it. So if you're doing both you're kind of not changing anything to first order.

In terms of physical effects, someone who is doing intermittent fasting is attempting to deplete their body’s glycogen stores: your body very carefully regulates blood sugar (glucose) and stores a bunch of extra blood sugar in these hairballs called glycogen, stored mostly in the liver and in the muscle: then when your body needs more blood sugar circulating, it chops sugar bits off of the ends of the hairballs, or if it has too much sugar it grows the ends of the hairballs.

The impact of fasting is a difference then between your activity and your intake, right? So if I want to really deplete my glycogen stores completely, I'll go run a marathon, that'll do it. Thinking really hard, like a game of chess, can too. Key to understanding the difference between fasting and late eating/breakfast skipping, is the fact that at night mostly we sleep or sit lazily in front of a TV or so. So by binging food late at night you are kind of doing the exact opposite of fasting, you are raising your blood sugar at the exact time that your body stops moving and your brain isn't thinking so much, so your body isn't processing that blood sugar. You fill up your glycogen stores this way!

What happens when they get too full? Your body raises its blood concentration of a hormone (signaling molecule) called insulin. Muscle cells can take in blood sugar whenever they want, but fat storage cells have a “lock and key mechanism” where the channel to let in the blood sugar is controlled by this hormone, they cannot take it in without the insulin. So you get this insulin spike while you sleep, body is saying “I have too much glycogen, please store some blood sugar as fat so that I can shrink these glycogens into the bloodstream.” And you put on weight. But, by itself this is healthy weight. This is what's called subcutaneous fat, the fat that's living out by the skin, in adipose tissue. What will kill you is the visceral fat, which is a distortion of this process.

To understand this, understand that a cell might not want to take on more blood sugar either. In programming terms, the bloodstream is a message bus, the insulin is a message on that bus, and the cell might want to NACK the message. A fat cell can only hold so much fat before it bursts, when it gets to bursting it needs to divide into two fat cells that are half full. So it needs to shut down, to say no no I am not taking the sugar in right now.

The difference between programming and biology is that these are analog signals, so rather than a binary on/off, ack/nack, the cell reduces its sensitivity to insulin, “I just won't take on so much blood sugar right now.”

Type 2 diabetes, what this study is talking about, is a disorder where you have a high blood sugar because your body is developing an insulin resistance. So if one cell down-regulates insulin, great, it is protecting itself. But if all your cells do this at the same time then the body can't clear the blood sugar. So what do you do? Analog system. You spike the insulin even higher. “But Mommy I don't want more”—“well TOO BAD finish your plate, we can't have this food going bad in the fridge and we don't want to attract bugs and DO AS I SAY!!”.

As this starts to happen, you start getting fat deposits in places that are not off in secure storage out by the skin, but are sitting close to the organs where they can do real damage to the ongoing function of your cells—visceral fat.

I hope that helps, the idea is that to first order there is no difference in the amount that you fast but only when you are fasting, and the serendipitous overlap of fasting with sleep and low activity is potentially disturbed by late eating and skipping breakfast, and that could be dangerous because if you are already in that hypernourished situation where you are putting on weight, then this puts potentially a larger strain on it during the night time, like it would be worse if you did late night snacking and also had breakfast, but the idea is that maybe even when you try to skip the breakfast to make up for it it isn't all a wash, it really matters when you eat maybe.




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