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Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

ncbi.nlm.nih.gov

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Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#51
post #38

Earlier quoted context omitted.

And BMI says nothing of body fat percentage Can have higher BMI and lower bodyfat I'm not convinced BMI is a useful metric

Why do people keep making this argument? It's a terrible argument. BMI and body fat are extremely strongly correlated. People with a very high BMI are all obese or morbidly obese. And people with a very low BMI are almost all underweight. BMI is a very simple, easy to calculate and useful metric. It works across countries and across time. BMI is just one metric. It doesn't tell you everything and knowing only the BMI…

> People with a very high BMI are all obese or morbidly obese.

That is tautological - obesity is defined in terms of BMI. BMI over 30 is obese.

Arnold Schwarzenegger is 6'2" and weighed 235lbs at contest (30.2 BMI) and 260lbs in the off season (33.4 BMI). So much for your "all" claim.

Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#52
Damn. I thought skipping breakfast is good for adults (I'm 40).

Anyway, let's say late night eating is bad. But many programmers I know (including myself) are more productive at night. But working = hungry. How do you handle this contradiction?

Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#53
post #3

This seems similar to intermittent fasting but with seemingly the opposite effect, I wonder what I'm missing.

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.

Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#54
post #51
post #38

Earlier quoted context omitted.

Why do people keep making this argument? It's a terrible argument. BMI and body fat are extremely strongly correlated. People with a very high BMI are all obese or morbidly obese. And people with a very low BMI are almost all underweight. BMI is a very simple, easy to calculate and useful metric. It works across countries and across time. BMI is just one metric. It doesn't tell you everything and knowing only the BMI…

> People with a very high BMI are all obese or morbidly obese. That is tautological - obesity is defined in terms of BMI. BMI over 30 is obese. Arnold Schwarzenegger is 6'2" and weighed 235lbs at contest (30.2 BMI) and 260lbs in the off season (33.4 BMI). So much for your "all" claim.

Arnie is also called an outlier. You don’t dismiss BMI just because. A doctor will factor that in before declaring a patient unhealthy. Otherwise, it works for most people and might be appropriate in large studies.

Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#55

Would be interesting to see another study with people who do both breakfast skipping and skipping late-night eating. When I was in my 30s I was a typical woefully sedentary "IT potato" with more than a few extra kilograms around the waist, but today in my early 40s I manage to stay slim and free from diabetes despite being just as sedentary, and I'm convinced that my intermittent fasting is contributing to it: These…

Yeah, I think I'm getting good results by having a line of 7 as the latest I'll eat. The after 10 snacks were obviously bad, but it is impressive how invisible they were to my attention.

Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#56
post #37
post #24

Earlier quoted context omitted.

Pretty much only true if you are a body builder or someone else with an unusual amount of muscle mass relative to your height. For the vast majority of people though BMI is fine.

There is little point of doing a study based on BMI when what you want is body fat. BMI is imperfect. It’s fine when you want to give people a quick metric for them to assess their fitness by themselves. People who are extremely fit with a high BMI already know they are extremely fit after all. It’s not fine when you want to analyse the effect of different life styles.

It’s easier to gather hundreds of people’s BMI for a study than it is to measure fat, which can also be misleading depending on the method used.

Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#57
post #51
post #38

Earlier quoted context omitted.

Why do people keep making this argument? It's a terrible argument. BMI and body fat are extremely strongly correlated. People with a very high BMI are all obese or morbidly obese. And people with a very low BMI are almost all underweight. BMI is a very simple, easy to calculate and useful metric. It works across countries and across time. BMI is just one metric. It doesn't tell you everything and knowing only the BMI…

> People with a very high BMI are all obese or morbidly obese. That is tautological - obesity is defined in terms of BMI. BMI over 30 is obese. Arnold Schwarzenegger is 6'2" and weighed 235lbs at contest (30.2 BMI) and 260lbs in the off season (33.4 BMI). So much for your "all" claim.

The model disregards ridiculous outliers like world class bodybuilders in order to be simple and useful for the other 99.999% of society.

Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#58
post #51
post #38

Earlier quoted context omitted.

Why do people keep making this argument? It's a terrible argument. BMI and body fat are extremely strongly correlated. People with a very high BMI are all obese or morbidly obese. And people with a very low BMI are almost all underweight. BMI is a very simple, easy to calculate and useful metric. It works across countries and across time. BMI is just one metric. It doesn't tell you everything and knowing only the BMI…

> People with a very high BMI are all obese or morbidly obese. That is tautological - obesity is defined in terms of BMI. BMI over 30 is obese. Arnold Schwarzenegger is 6'2" and weighed 235lbs at contest (30.2 BMI) and 260lbs in the off season (33.4 BMI). So much for your "all" claim.

I wouldn't make the all claim, but you must admit that a world renowned body builder is an extreme outlier. Obviously a DEXA scan would be far more accurate, but it seems clear from the literature I've read that BMI is a pretty good guide for most people.

Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#59

Earlier quoted context omitted.

And BMI says nothing of body fat percentage Can have higher BMI and lower bodyfat I'm not convinced BMI is a useful metric

yeah... but the likelihood that you have a high BMI because you're just so jacked is low. It's not perfect, but it's a good metric.

Most people you see at a gym will probably be classified as 'overweight'. The fact of the matter is muscle is counted against you in BMI, and it takes very little to cross into the 'overweight' threshold. I would have to cut down to around 12% or lower body fat to be considered 'healthy', and I'm far from jacked.

1. Being sub 12% body fat (the highest BMI that would be considered healthy) is arguably unhealthy in and of it's own

2. Being on the low end of healthy would be, if my math serves me, -2.5% body fat

3. BMI does not distinguish between unhealthy / overweight, and fit / healthy (which should be the primary goal of such a metric?)

4. BMI aligns the best outcomes with those that will minimize muscle mass

It's not that BMI does not have it's place, but let's call a spade a spade.

Re: Effect of Breakfast Skipping and Late Night Eating on BMI with Type 2 Diabetes

#60
post #51
post #38

Earlier quoted context omitted.

Why do people keep making this argument? It's a terrible argument. BMI and body fat are extremely strongly correlated. People with a very high BMI are all obese or morbidly obese. And people with a very low BMI are almost all underweight. BMI is a very simple, easy to calculate and useful metric. It works across countries and across time. BMI is just one metric. It doesn't tell you everything and knowing only the BMI…

> People with a very high BMI are all obese or morbidly obese. That is tautological - obesity is defined in terms of BMI. BMI over 30 is obese. Arnold Schwarzenegger is 6'2" and weighed 235lbs at contest (30.2 BMI) and 260lbs in the off season (33.4 BMI). So much for your "all" claim.

> Arnold Schwarzenegger is 6'2" and weighed 235lbs at contest (30.2 BMI) and 260lbs in the off season (33.4 BMI). So much for your "all" claim.

Most people aren't Arnold. Outliers don't count in studies, for very good reasons.

It is understood that when we say "all" we mean "close to 99%", and for 99% of the population with a BMI over 30, they are overweight.

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