Comment by buzzcut | Hacker News Reader

Comment by buzzcut | Hacker News Reader

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Unfortunately I can only summarize.

On the starvation study it's merely one example that highlights how calorie restriction affects people. Yes, it's an extreme version, but it is different only in degree from any other calorie restriction, and when people try to reduce by X calories, it's probably a linear effect; more restriction, more of these effects. Oddly though, fasting tends not to have these effects, it's only in sustained calorie restriction, so fasting in various forms is one of the tools people can use to lose weight.

As for the lowered energy output Jason Fung wrote (pg. 53 of the Obesity Code, "One major problem is that the basal metabolic rate does not stay stable. Decreased caloric intake can decrease basal metabolic rate by up to 40 percent. We shall see that increased caloric intake can increase it by 50%."

If you want to learn more here are some sources:

Jason Fung - The Obesity Code: http://www.amazon.com/gp/product/B01C6D0LCK/ref=dp-kindle-re...

Robert Lustig on sugar: https://www.youtube.com/watch?v=dBnniua6-oM

and also here: https://www.youtube.com/watch?v=nxyxcTZccsE

Peter Attia on ketosis and fat: https://www.youtube.com/watch?v=NqwvcrA7oe8

Reversal of diabetes by diet, also Jason Fung: https://www.youtube.com/watch?v=mAwgdX5VxGc

> On the starvation study it's merely one example that highlights how calorie restriction affects people. Yes, it's an extreme version, but it is different only in degree from any other calorie restriction, and when people try to reduce by X calories, it's probably a linear effect; more restriction, more of these effects. Oddly though, fasting tends not to have these effects, it's only in sustained calorie restriction, so fasting in various forms is one of the tools people can use to lose weight.

No dude, you are ignoring the fact that these people did not have ample fat stores. It is completely unreasonable to expect that obese people would behave the same while restricting calories than people who are already borderline starving (4% BF). These aren't effects of caloric intake restriction, they are effects of caloric restriction in general, which is a state obese people are not, have not been in for years and will not be in for years.

> One major problem is that the basal metabolic rate does not stay stable. Decreased caloric intake can decrease basal metabolic rate by up to 40 percent

This is basically unrelated to your statements about insulin though, so don't conflate the two. This statement does not support the idea that obese people cannot harvest energy from their fat stores, it supports the idea that you get less energy output from less energy input which is almost tautologically true.

> "No dude, you are ignoring the fact that these people did not have ample fat stores."

I don't think I am ignoring it. You seem to be asserting that their issues with calorie restriction were lack of body fat. There is no evidence for that I am aware of. A simple rejoinder based on anyone's experience, do fat people get hungry? If they do, why? They have all that energy available. But I don't need to rely on arguments like that, since in the vast corpus of research on this at this point, it's pretty well established that calorie restriction by itself (even with exercise) does not work long-term. The failure rate is astronomical and it is in part due to what plain old calorie restriction as we've been told to do it does to metabolic energy and also due to the psychology of hunger. Also, and this is very important, a full fast does not have these effects according to the evidence. People can totally abstain from food for very long periods of time (depending on body fat), with very little hunger. It is smaller scale calorie reductions, without breaks (like the breaks intermittent fasting provides) and without much dietary fat since fat is highly satiating, that cause these reactions to calorie restriction.

> "This is basically unrelated to your statements about insulin though, so don't conflate the two."

Again, I'm not. I was responding to the request for a source on the idea of energy output reduction in response to lower calories. I'm not claiming there is a link between energy output reduction and insulin.

Fat people can get energy from fat stores, just not in the way we are typically told. If it was impossible to get energy from fat no one would ever lose weight, which is trivially and obviously not true.

> You seem to be asserting that their issues with calorie restriction were lack of body fat.

No I'm asserting that what happens to people's bodies at 4% body fat when in severe caloric restriction is very different than what happens to people's bodies at 40% body fat with severe caloric restriction, and so we can't apply the metabolic damage/starvation models to fat people. Fat people just need to eat less, and the issue basically comes down to compliance. How do we get people to stay on a healthy diet long term?

> do fat people get hungry? If they do, why?

Because, as even you have shown, hunger is not a reflection of your bodies actual caloric needs, it's hugely a reflection of blood sugar levels, among other htings. Given enough time (in the order of magnitude of minutes to hours) in an obese but otherwise healthy person fats will be broken down and blood glucose will increase and hunger will decrease. It's getting through that period that is a mental compliance issue, but not otherwise physiologically challenging.

> The failure rate is astronomical

Again, this is a compliance issue. People absolutely lose weight on caloric restriction, and starvation issues like low metabolism do not become an issue until you are very low body fat. You simply do not see obese people going into so-called "starvation mode." In fact there are a few cases, though admittedly not many, of obese people that abstain entirely from eating for months at a time without long term "metabolic damage."

> People can totally abstain from food for very long periods of time (depending on body fat), with very little hunger.

I think we basically agree, then, that it's mostly a compliance issue and not an issue of caloric restriction working or not, and also that hunger is not a reflection of the body's actual metabolic state (especially in obese people).

> Fat people can get energy from fat stores, just not in the way we are typically told.

Fat people get energy from fat stores in the same way skinny people do. Very skinny people on severe caloric restriction are not a good model for the general population.

> "Fat people just need to eat less, and the issue basically comes down to compliance.:

On oversimplification, but the crux of the issue. The astronomical failure rate is because of compliance. The prescription you seem to be suggest is "comply more! comply better!" but the biology of this is exactly why it fails so often. The type of food you eat is what sets you up for sustainable long-term success or its opposite. What you wave away with a wash of the hand--compliance--is the reason people fail and more willpower is not the issue and not a solution. It's a dysfunction of the hormones brought on by high insulin resistance brought on by excessive sugar and flour, which becomes a hunger trap, unless you add fat to your diet, which is exactly what people are told not to do. So, I do think hunger tends to differ when you suffer from fatty liver disease and insulin resistance. People can endure calorie restriction and lose weight for a while doing low-fat but they do not stay on it. Saying that people should just comply more is like telling someone with sleep apnea to sleep better. They need a different intervention.

edit--A failure rate of 80-90% is not an anomaly, it's a colossal failure. It's not something to be overcome, it's an indication of wrongness. By asking for more compliance you are asking people to fight their biology and they will lose this fight. Instead the intervention should be to employ their biology as their ally, and lose weight more easily and without much hunger and that's possible. It's just not helpful to tell people to eat less. We've been telling them that for forty years.

(Side note. The 4% bodyfat in the UofM study you mention is an assumption of yours, and not the starting weight of the people in the study. I think you're unfairly dismissing the study and presenting it as if it's a binary condition between starving/not starving, and that may be a thing, but it's not certain that it is. I'm merely cautiously using it as evidence that calorie restriction is difficult (actually more than difficult) to maintain, which anyway we all know from experience. It would be good to explore other studies on the topic). Intermittent fasting, for example, is vastly easier than consistent calorie restriction, and you're consuming the same number of calories as calorie restriction (if you design it right). That's not a matter of willpower, that's a different intervention).

Unfortunately I don't have time to continue the conversation, but take the time to explore some of the links I posted (there are tons more)--they go into way, way more detail and make the argument better than I have.

I don't really disagree with a lot of what you are saying. Note that you've backed down from low calorie diets cause metabolic damage to low calorie diets are mentally difficult to sustain which I agree with.

You've offered introducing fats as a way to stave off hunger (aka increasing satiety) but introducing fats are far from the only way to increase satiety. Introducing fiber, for instance, is another way.

You also seem to be in favor of a ketogenic diet. Let me say that I totally believe that a keto diet is a great way to eat healthily and boost compliance for some people. Others have a really hard time tolerating large amounts of fat, and so we still need to find alternative solutions for them.

I agree that simply telling people to have more willpower is not the solution, but I think it's important to recognize that the diet is not causing physiological damage to the vast majority of people (it's not the insulin spike in and of itself that causes damage, it's what happens after that, ie: more food intake). So maybe we can attack this from the pure will power front and leave the diet alone (or maybe not, but let's be deliberate about what we are doing).

Regardless, the UofM study is heavily discredited and I still maintain that it is not relevant to what you are arguing either way: the study is designed to study extreme starvation and famine. Brink of death type stuff. Obese people who feel hungry are not that. We know this because if you don't feed them they don't die.

FWIW I actually have read/watched all the links you've posted (I had before this conversation as they are all relatively well known), and I still hold by all my points.

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