This is well known by bars in many locations that pass out free lollipops and hard candies as closing time approaches. Anecdotally it causes violent altercations to plummet.
>> When you increase such “cognitive load” on someone’s frontal cortex, he or she exhibits less self-control on subsequent tasks—just like muscle that’s been exercising hard, then balks at having to move you one step more. <<
Everyone cites this as fact when in reality the science behind it is very shaky.
A similar misconception is "I need glucose therefore I should eat sugar" .
The most stable way to supply blood glucose is by eating fat. If blood glucose is high and circulation is low, then exercise maybe in order, more than additional eating.
"""acetic acid (in the form of acetyl-CoA) is used to partially produce glucose; acetyl groups can only form part of the glucose molecules (not the 5th carbon atom) and require extra substrates (such as pyruvate) in order to form the rest of the glucose molecule. But a roundabout pathway does lead from acetyl-coA to pyruvate, via acetoacetate, acetone, acetol (hydroxyacetone) and then either propylene glycol or methylglyoxal."""
Just answered your initial comment that was "The body cannot convert fat into glucose at all".
So it's a little moving-the-goalposts disingenous to brush this off as "it's not significant for our daily glucose requirements", when your initial claim was much stronger and this refutes it.
As I'd indicated in another response, I wasn't aware of pathways other than straight carbs or synthesis from protein (and knew of but forgot about the glycolysis/pyruvate pathway). I appreciate the new information.
My question simply as read: do you know of rates of production of this pathway? If it cannot meet ~100g/day or a significant fraction of that, then it's not really materially significant, though it is of interest. If it can, well, then, that changes things.
Answering the question or stating "I don't know" would be acceptable.
Try doing a 100km bike ride on an up/down road circuit, with fat as the main fuel.
EDIT: lol, downvotes. This is not about your metabolism while you're sitting on a chair at work, typing on a keyboard. This is about extreme endurance. I suggest you actually go ahead and try it, before thinking you've formed any sort of informed opinion on the subject.
It is fair to point out (which the article does as well) that the athletes were running at 75% of V02 max, which is lower than when racing in cycling. I ride a lot, and anecdotally I had a cycling teammate that changed his diet to consist of primarily fats for 6 weeks. The first few weeks his body was adjusting and his endurance and power dropped dramatically as you would expect. After 4 weeks, though, he had come back and had a really strong season.
The way I understand it is that as intensity increases it becomes more difficult for the body to convert fat for a large source of fuel, and glycogen becomes the largest contributor to energy. I know the feeling of a "bonk", when glycogen depletes, is a really strange one and all fuel is coming from fat at that point and intensity has to drop by quite a bit in order to continue.
I have done exactly this, and it's been fine. I regularly ride centuries around the Bay Area on a sugar free diet.
Your body definitely needs time to adapt to a fat based diet, but it can satisfy all your energy needs.
I've also done centuries with sugary 'energy' foods. I frequently found myself having to pull over or dangerously balance in order to keep my blood sugar high by dosing myself every 45 minutes. Your stomach churns, your teeth feel awful, being constantly in service to your legs. Burning the fat is a much more comfortable proposition.
"Try doing a 100km bike ride on an up/down road circuit, with fat as the main fuel."
I am not an extreme endurance athlete, but I have heard multiple anecdotes of extreme endurance athletes eating cheese pizza slices during their 100-200 mile runs. It's actually a fairly common theme ...
ALSO: Do NOT meta-discuss your own downvotes. Don't interrupt the discussion to talk about the scoring.
> Do NOT meta-discuss your own downvotes. Don't interrupt the discussion to talk about the scoring.
Nah, let's do exactly that. I see too many controversial posts which are otherwise good quality and contribute to the discussion, get downvoted because people don't agree with them. I don't care what pg says - downvoting merely for disagreement is fucking stupid, and it's lazy.
If I wanted a hivemind I'd go to proggit. When this community votes on posts based on quality, and not on who wrote it and whether they agree, then we can call people out for complaining about downvotes. Until then (i.e. until never, probably), if you feel you're being unfairly downvoted, bitch about it as loudly as you want - you will get at least one upvote from me when you do.
I work construction, I managed eating a very strict ketogenic diet for several months. There's a brief window where your energy is low in the beginning, but after a month I found I had far more endurance than I did before, and than I have now since stopping the diet. My job performance not only improved, but I stopped eating lunch because I no longer needed to recover energy. (edit: an extra anecdote here, it's the only time since I was a kid that I've been hyperactive in the evening. It's also the only time I've actually wanted to exercise, and often times not only wanted to but had to otherwise I'd get insomnia due to my body feeling 'too awake'. I'd be making a cup of tea and doing jumping jacks waiting for the kettle to boil. I can't count the number of times I got out of bed to go work out because I couldn't sleep.)
Also, doing a 100km bike ride with fat as the main fuel would actually be exceptionally easy if you used the proper technique, because the entire purpose of the gearing system on racing bikes is to ensure your exertion remains the same. It would just require training with this goal in mind, like Timothy Oslon who's a successful ultramarathon runner.
> I suggest you actually go ahead and try it, before thinking you've formed any sort of informed opinion on the subject.
I would suggest you do the same, because you don't seem too well informed either.
Unfortunately, the link does not go into any detail and there is no reference to the source. I've heard about "apparent adaptations", but never specifics. So not sure they do exist.
Researchers who lived with the Inuit (Vilhjalmur Stefansson etc.) did not have any problems following the Inuit diet.
There has been some debate about the actual Inuit diet, specifically, about its carbs content. It seems that fresh and/or frozen flesh contains a significant amount of carbs (in the form of stored glycogen). This is a good review[1] of the whole thing.
Side note: I've been on a ketogenic diet (high fat, very low carb) for a couple of months now and, cognitively, I feel far sharper and more alert than at any point I can recall. And more stable -- no more post lunch slump.
Great, we can just go ahead and file that in the garbage with the rest of the anecdotes. Notice how everyone who is happy with their diet says the same thing you just said, no matter what their diet is?
Unfortunately there is not a whole lot of research on ketogenic diets outside of treating cognitive diseases. But it can be argued that if it helps prevent them in people with declining brain functionality, it improves brain functioning in healthy people.
That could be argued, but the counter argument would be "that's a completely baseless and unfounded argument". And there isn't evidence that it helps prevent disease in people with declining brain functionality. Your link says "we should do some research on that" not "there has been research on that".
I also feel much more sharp on coffee. But as a heavy coffee drinker, pretty much every available study shows that I am just as sharp as I would be without the black stuff.
Turns out my own feelings about sharpness has absolutely nothing to do with congnitive ability. Who would have thought?
That conclusion is way too strong. Your feelings about sharpness on coffee has nothing to do with cognitive ability. On a ketogenic/low-carb diet, maybe they do? (I hope, but doubt, that there are studies on this.)
Sure, anything is possible, but let's not pretend it holds true unless tested. Make that unless rigorously tested, since it would be an outlier among cognitive self-assessments.
I had the same experience on a keto diet. There's also nothing like the euphoria of having so much energy after a long day (I work construction) that at 2am you have to get out of bed, still wide awake, and go down stairs to do a hundred push ups to burn off some energy.
In my case, ketosis was great to fix my metabolism and kickstart fat loss when I was overweight. However, after a couple of years in ketosis, I started to get some worrying symptoms (mainly brain fog and constipation).
Now I am eating about 200g/day of carbs (mainly from rice and veggies) and I feel much better. My weight remains the same.
This is a good intro to the potential problems of chronic ketosis [1].
>A similar misconception is "I need glucose therefore I should eat sugar" .
That's not a misconception, it is reality. It is amazing how many people on HN really hate science. Diabetics are told to eat juice or candy when their blood sugar is low for a reason.
>The most stable way to supply blood glucose is by eating fat
> It is amazing how many people on HN really hate science.
Counterpoint: medical science is insanely difficult and expensive, due to individual variations in genetics and lifestyle, and the huge number of variables that it is effectively impossible to completely control for. This leads to research that is tainted by the incentives of those agents that afford the expense, and results that tend to be correlation more often than causation.
That's not to say that we should ignore the science we do have; rather, we shouldn't fall into the trap of assuming we can model biology as precisely as astrophysics. Sometimes the illusion of knowledge is more dangerous than ignorance.
None of that justifies what amounts to "gravity don't real" being posted here constantly when it comes to anything remotely related to nutrition. Biochemistry is a real science. We know what we're doing. "I want to pretend fad diet salesmen are equal to scientists" is not reasonable.
Energy generation is much more efficient once you go through ketoadaptation. It involves fatigue like symptoms that can last up to several weeks during the transition though. But once you go through it, you feel quite amazing.
> It is amazing how many people on HN really hate science
Inflammatory language like this (as well as in https://news.ycombinator.com/item?id=8696794, https://news.ycombinator.com/item?id=8696817, and other comments you've posted) adds to the problem.
Assuming you're 100% correct on facts, railing against perceived idiots merely impedes the communication of the facts. It discredits your arguments, and it poisons the discourse. We all need to edit this kind of thing out of the comments we post to HN.
I'm a Type 1 diabetic. No one in the medical field, and run I've run in to my fair share of idiots along the way, has ever told me to "eat candy" when my blood sugar is low. The medical advice is that I should ALWAYS keep glucose on my person in a liquid or tablet form in case of a low blood sugar as these will bring blood sugar back up the quickest.
If I do not have glucose on my person then I'm advised to drink anything that is "liquid sugar" - juice, pop, milk (lactose) because it raises the blood sugar quickly.
But you need to consider this is because our bodies are DEFECTIVE. When my blood sugar goes to 30 (been there, done that) I need a blood sugar spike RIGHT NOW. And by right now I mean before I pass out, slip into a coma, and DIE.
So when I am presented with a number so low that I am about to be seriously fucked, and I don't have my tablets with me, I'll eat every fucking carbohydrate in sight because a high blood sugar might kill me in 20+ years, but a low can kill me right now.
Outside of potentially LIFE THREATENING low blood sugar levels diabetics are encouraged to try to stay away from foods that fall into the high glycemic index categroy. This is because they raise blood sugar fast, and then they crash back down just as fast. This is what most of us diabetics refer to as the "Roller Coaster"; and we do not like coasters.
The really great thing about healthy non-diabetics is your body is really good at self regulation, so your "lows" will likely never go below 70 (e.g. Not dangerous), and even after gorging yourself on an entire pizza and chasing it with a 2 liter bottle of Code Red Mountain Dew your body will still keep your blood sugar maxed at an also healthy 100.
So please don't talk like you understand diabetic science or that it in anyway relates to normal, healthy functioning adults. It is the equivalent of trying to say that someone without cancer should get chemo, because it helps people with cancer. It's not like you are going to pass out and die or possibly have your blood turn into acid and poison you to death (yes this is a real risk for a Type 1 diabetic http://www.diabetes.org/living-with-diabetes/complications/k...http://en.wikipedia.org/wiki/Ketoacidosis)
Never did I say diabetics can't eat sugar. Carbohydrates are fuel and all carbs are sugar. It says right there on the ada link I provided a link to above, " If eating a food with a high GI, you can combine it with low GI foods to help balance the meal. - See more at: http://www.diabetes.org/food-and-fitness/food/what-can-i-eat...
And the bottom line is the dietary dos and do nots for diabetics just don't apply to healthy people. They are on a different playing field.
1) Hearing way too many people say diabetics should do X,Y, or Z when they don't know what they are talking about combined with your original post.
On the first point,
>>A similar misconception is "I need glucose therefore I should eat sugar" .
>That's not a misconception, it is reality. It is amazing how many people on HN really hate science. Diabetics are told to eat juice or candy when their blood sugar is low for a reason.
Yes, sugar is absolutely necessary for energy. Fat as fuel is pseudo science BS. On the other hand most people consume way more sugar than is necessary and the sugars we take when our blood sugars are low are not the best sources of sugar for a general diet and long term fuel source.
On the second point,
>>The most stable way to supply blood glucose is by eating fat
>That is also too slow to be of any use."
Fats, fiber, and protein are pretty great for fueling stabilized blood sugar since they lower the GI of carbohydrates. While this is not good for low blood sugar, it is great for maintaining stable lower fluctuating blood sugars. So the general advice for a healthy person to eat more fats and less carbs is overall some pretty good as advice as there is very strong evidence that it lowers risk of Type 2 diabetes. As for Type 1, obviously you're just fucked no matter what you do.
Anyway, was not trying to be a "prat", and the TC is wrong on the whole point of
>A similar misconception is "I need glucose therefore I should eat sugar".
Your post came off to me though as the opposite extreme; while not explicitly stated, it seemed to imply that the people saying they should eat/drink high GI food/drinks to raise blood sugars, but really they should probably be eating more lower GI foods.
Try reading my posts instead of making up things to pretend they say. All I said is "consuming sugar raises your blood sugar". This is not controversial, and just because the advice is given to diabetics, does not mean it doesn't apply to everyone else.
> The most stable way to supply blood glucose is by eating fat.
I would like to see a citation for this. My metabolics text book says that generally fat cannot be made into glucose. Only the glycerol bit can, and that is only a small fraction of the calories in fats.
There may be just a germ of truth in what you say, in that for some people eating large amounts of carbohydrate leads to drastic fluctuations in serum glucose.
When you are eating excessive sugars and carbs like most people today, your body doesn't burn fat. You only use sugars for energy. That's why you have your energy levels constantly up and down.
I have been on ketagonic diet last 3 months. I eat no sugars and less than 50gr carbs. My energy levels are always stable now, lost 20lb. I don't need glucose for energy.
I see it as winter mode vs summer mode:
- If it's is summer there are sugars and carbs. So, your body keep storing as much fat as possible and uses carbs for energy and pushes you to eat as much as you can. Making you feel hungry all the time so you eat more and store more fat.
- if it is winter, there are nothing much to eat, so your body uses fat as energy.
The problem with modern world is that there are just so much food and carbs around us that we are always in summer mode.
There is no metabolic pathway that converts lipids to glucose. Your body will not be able to metabolize glucose from your diet if you're eating only fats.
The metabolic pathways which do produce glucose are:
1) Eat starches.
2) Eat protein.
Starches are converted directly to glucose. Protein can be converted to glucose by a process called gluconeogensis. This is what happens under either a starvation situation (in which case the protein is supplied from body tissues -- skeletal muscle and eventually organ tissue), or under a ketogenic diet, in which dietary protein could be utilized.
While dietary glucose is apparently not necessary, it's also not a bad thing, provided you're not getting excessive quantities or low-fiber sources which trigger an excessive insulin response.
That said: the typical Western diet provides more than ample glucose and starches, often in an overly refined form. That can trigger lipogenesis, in which excessive glucose is converted to lipids and stored as fat.
There may exist such a pathway, but we need to check its capacity, efficiency and by-product production. Maybe it is a pathway for critical situations only and we should not relay on it for prolonged periods of time.
Maybe the carbohydrate to glucose pathway is for critical situations only and we should not relay on it for prolonged periods of time.
These are evolutionary adaptions that let us extract energy efficiently from our environment, maybe yesterday's sensationalist news about our alcohol dehydrogenase efficiency is proof that we should use alcohol for all energy needs.
I've the heard the pathway is gluconeogenesis[1] . From what I've read we need roughly 100g of carbs a day, and we can create all of it via gluconeogenesis.
Now, what i really wonder is; if we see diabetes from abusing the carbohydrate pathways, then what disease comes from abusing the ketone/gluconeogensis pathways ?
One could argue that this study is showcasing a strategy for people of a certain mindset to improve their willpower; what it doesn't offer is proof that the many other studies that have supported depletion theory use "very shaky" science.
the results highlight the critical role of beliefs about willpower in self-control performance
I don't know how generalizable the results are, and I'm not making claims about its generalizability. I'm simply refuting the notion that it's wholly incompatible with depletion theory. Speaking personally, I would have appreciated some notion of how common any belief whatsoever is for people.
My instinct is that these articles are both right. Yes, your emotions and impulses are more difficult to control when you're tired and hungry (WSJ article) and yes, with effort you can still control them (stanford article). Much of psychology is "shaky" science - the underlying subject is just so damn complex.
What you quoted and what the study talks about are entitely different things -- the article focuses on the effects (or lack thereof) of sugar on willpower.
Not about whether increased cognitive load means less self-control on subsequent tasks.
You mistakenly interpret Dweck's Stanford study as somehow undermining Baumeister's research into self-control, when in fact Baumeister's body of research actually tackles this very phenomenon. Baumeister's research showed that under less exaggerated levels of depletion, you could mentally overcome the self-control issues. But after a certain point, when depletion gets severe, the mentality described by Dweck actually starts causing you to do worse and worse.
The reality is that science behind it is actually some of the most compelling and thoroughly thought out from the field of behavioral psychology.
Emotions can do a math kind of thing (additive, subtractive, multiplicative and such) from our personal histories and day to day, unrelated tasks. Lots of people project or distort their emotions in various ways, or they rationalize away emotions using psychological analysis terms like projection / and an observation of state changes based on input/output. Having it perfectly under control feels like being a computer sometimes.
People learn and create different ways to handle emotions. People experience differences and similarities in life experience. People resolve and analyze their histories, present and future evaluations differently, similarly, if at all. People have different temperaments, or similar. People can track their data independently to attempt to control their reactions internally to the external world, but life does things that make handling response not always controllable.
I can't say anything about your state anymore than I both simultaneously understand and do not understand my own.
This is why I drink a "bulletproof" coffee in the morning at about 7am. Basically, coffee with butter and MCT oil. Then I have a breakfast of poached eggs and bacon at about 9am.
My brain and focus is just way better running on fat than on glucose.
> My brain and focus is just way better running on fat than on glucose.
Your body runs on sugar not fat. Fat will be transformed into sugar to be used as energy in your body. With that said, it won't create a huge spike in your blood sugar like drinking a soda, and won't cause a giant release of insulin.
The TCA is cycle is the actual main energy generating step.
Other times fat absolutely is converted to sugar. It all depends on the metabolic needs of the body and one building blocks are available, and what protein "workers" are able to use the ones that are available.
For example, fatty acid synthase converts acetyl coa back to a fatty acid [3].
That wasn't my claim, please don't misquote me. What I actually said was "Other times fat absolutely is converted to sugar." There is a very significant difference.
Your body can run on either glucose or ketones. When you follow a low carb, high fat diet your body uses a higher percentage of ketones as energy (derived from fat). It's a much more stable form of energy since it is a constant and even supply instead of the spikes and lows from traditional carb heavy diets.
If you are referring to gluconeogenesis, yes, fat and protein can be converted to glucose but the amounts are fairly negligible. If you eat fat or have fat the body will convert the fat to ketones and use that in the absence of glucose. It's a much more efficient metabolic pathway than going through gluconeogenesis. The vast majority of the body functions quite well on ketones for energy. Most people are not able to metabolize fat at the rates required to avoid fatigue without undergoing ketoadaptation though. It takes anywhere from 3 days to 3 weeks depending on the individual and seems to be correlated with insulin resistance.
it is good to eat honey or fruit fro your sugar, not table sugar, as table sugar(white death) gets in your blood very quick causing insulin spike, which is bad and bad only, unless you completely deprived of energy like in long distance race.
this stupid sensationalist articles designed to glorify consumption of junk food are just pathetic and should not be on top of hacker news...
Fruit has small amounts of fiber that slightly slow absorption. Honey does not. It has the exact same effect as any other sugar. Rather than "feeling" it, try measuring it.
One of the researchers mentioned in the article, Roy Baumeister, wrote a book that I enjoyed (entitled "Willpower"). He gave a talk about willpower and glucose levels which you can see some of here: https://www.youtube.com/watch?v=vefDeoXCBbk
It's not a completely pop-science book, more a translation of his research into an approachable lay-person format. I recommend it.
It is interesting. Though, as far as I know [1] glucose consumption varies only a little with brain usage. So either this thing is wrong, or nervousness because of lack of glucose has different mechanism that some lobes being hungry.
"Moreover, during a tough self-control task, circulating glucose levels plummet, consumed by hardworking frontal neurons. And, remarkably, self-control improves if subjects sip sugary drinks during the task (with control subjects consuming sugar-free drinks)."
Then is controlling urge to sip sugary drinks a doomed enterprise?
They should have had a control group that's completely off sugar. Sugar is an addictive substance and affects your psychology in a similar way to other addictive substances. You'd see similar results doing this experiment with smokers and cigarettes instead of sugar for example.
I've personally noticed that I get more irritated/angry 4-5hrs after my meal. This is quite evident for me in the morning when I delay my breakfast. Hence I try to time my meals religiously. Though getting irritated/angry doesn't affect my "willpower" as I can still keep my emotions in check and prevent them from ebbing out.
Coming back to the experiment, shouldn't the will power be benchmarked before testing for effects of glucose? Hypothetically, couldn't I get a study group of weak-willed people and enforce the WSJ article's premise as well as get a bunch of monks and refute it?
It's a little known fact that the brain can also be fueled by ketones by those following a ketogenic diet. Energy is more constant as the body is burning fat continuously instead of depending on constant feeding and the associated ups and downs in blood sugar. Those following a ketogenic diet report improved concentration and alertness.
Also, anything that overstimulates the reward system (sugar) will result in weakened willpower.
Are you referring to the fatigue from eating too much or not having any glucose in your blood stream? People who eat keto meals generally don't feel any food comas. You might be experiencing low blood sugar because the body is not burning fat as it should though. The only real way to get into ketosis is to remove carbs. Personally, I find it easier to just bite the bullet and fast for several days. Trying to ease out of carbs didn't work for me. This is probably a good resource to get started: http://www.ketotic.org/2012/05/keto-adaptation-what-it-is-an...
Gluconeogenesis (part of the starvation adaptation) occurs within minutes. Ketogenesis requires enzymes which take some time to be produced by the liver -- a few days, up to a week, for this to go into full effect so far as I understand.
And while the brain can run on ketone bodies (to a large extent), certain body tissues must have glucose, among them red blood cells.
How do get your muscles to look "full" on a keto diet? I'm talking bodybuilding here. I see almost everyone "carbing up" before a show specifically because of this. It also means if you want to follow this sort of diet you'll end up looking flat most of the time unless you leave the keto state.
Don't really see the point going low carb if you're lifting weights and calorie counting since you're replacing muscle glycogen all the time, there's not a lot of excess energy to be stored as fat unless you're eating way above maintenance.
103 comments
[ 3.0 ms ] story [ 174 ms ] threadEveryone cites this as fact when in reality the science behind it is very shaky.
See this study from Stanford: http://news.stanford.edu/news/2013/august/willpower-study-su...
The most stable way to supply blood glucose is by eating fat. If blood glucose is high and circulation is low, then exercise maybe in order, more than additional eating.
The body can't easily/quickly convert fat into glucose.
"""acetic acid (in the form of acetyl-CoA) is used to partially produce glucose; acetyl groups can only form part of the glucose molecules (not the 5th carbon atom) and require extra substrates (such as pyruvate) in order to form the rest of the glucose molecule. But a roundabout pathway does lead from acetyl-coA to pyruvate, via acetoacetate, acetone, acetol (hydroxyacetone) and then either propylene glycol or methylglyoxal."""
Minimum daily glucose requirements are on the order of 100g, possibly higher. If this pathway cannot sustain that delivery rate, it's not significant.
Just answered your initial comment that was "The body cannot convert fat into glucose at all".
So it's a little moving-the-goalposts disingenous to brush this off as "it's not significant for our daily glucose requirements", when your initial claim was much stronger and this refutes it.
As I'd indicated in another response, I wasn't aware of pathways other than straight carbs or synthesis from protein (and knew of but forgot about the glycolysis/pyruvate pathway). I appreciate the new information.
https://news.ycombinator.com/item?id=8698478
My question simply as read: do you know of rates of production of this pathway? If it cannot meet ~100g/day or a significant fraction of that, then it's not really materially significant, though it is of interest. If it can, well, then, that changes things.
Answering the question or stating "I don't know" would be acceptable.
Try doing a 100km bike ride on an up/down road circuit, with fat as the main fuel.
EDIT: lol, downvotes. This is not about your metabolism while you're sitting on a chair at work, typing on a keyboard. This is about extreme endurance. I suggest you actually go ahead and try it, before thinking you've formed any sort of informed opinion on the subject.
Here is a link to a summary, I couldn't find the actual research articles I was thinking of though.
http://www.pponline.co.uk/encyc/sports-nutrition-should-athl...
It is fair to point out (which the article does as well) that the athletes were running at 75% of V02 max, which is lower than when racing in cycling. I ride a lot, and anecdotally I had a cycling teammate that changed his diet to consist of primarily fats for 6 weeks. The first few weeks his body was adjusting and his endurance and power dropped dramatically as you would expect. After 4 weeks, though, he had come back and had a really strong season.
The way I understand it is that as intensity increases it becomes more difficult for the body to convert fat for a large source of fuel, and glycogen becomes the largest contributor to energy. I know the feeling of a "bonk", when glycogen depletes, is a really strange one and all fuel is coming from fat at that point and intensity has to drop by quite a bit in order to continue.
Our bodies are pretty amazing
There's only one thing that gets you out of it quickly - and that's a shovel full of carbs.
Your body definitely needs time to adapt to a fat based diet, but it can satisfy all your energy needs.
I've also done centuries with sugary 'energy' foods. I frequently found myself having to pull over or dangerously balance in order to keep my blood sugar high by dosing myself every 45 minutes. Your stomach churns, your teeth feel awful, being constantly in service to your legs. Burning the fat is a much more comfortable proposition.
I am not an extreme endurance athlete, but I have heard multiple anecdotes of extreme endurance athletes eating cheese pizza slices during their 100-200 mile runs. It's actually a fairly common theme ...
ALSO: Do NOT meta-discuss your own downvotes. Don't interrupt the discussion to talk about the scoring.
Well cheese is a good mix of protein and fat, and the base is full of carbs
Nah, let's do exactly that. I see too many controversial posts which are otherwise good quality and contribute to the discussion, get downvoted because people don't agree with them. I don't care what pg says - downvoting merely for disagreement is fucking stupid, and it's lazy.
If I wanted a hivemind I'd go to proggit. When this community votes on posts based on quality, and not on who wrote it and whether they agree, then we can call people out for complaining about downvotes. Until then (i.e. until never, probably), if you feel you're being unfairly downvoted, bitch about it as loudly as you want - you will get at least one upvote from me when you do.
Also, doing a 100km bike ride with fat as the main fuel would actually be exceptionally easy if you used the proper technique, because the entire purpose of the gearing system on racing bikes is to ensure your exertion remains the same. It would just require training with this goal in mind, like Timothy Oslon who's a successful ultramarathon runner.
> I suggest you actually go ahead and try it, before thinking you've formed any sort of informed opinion on the subject.
I would suggest you do the same, because you don't seem too well informed either.
http://anthro.palomar.edu/adapt/adapt_5.htm
Researchers who lived with the Inuit (Vilhjalmur Stefansson etc.) did not have any problems following the Inuit diet.
[1] http://freetheanimal.com/2014/03/disrupting-carbs-prebiotics...
note: Saccharose, which is Glucose + Fructose can help with that as well
So there's one anecdote for you.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2367001/
Turns out my own feelings about sharpness has absolutely nothing to do with congnitive ability. Who would have thought?
Now I am eating about 200g/day of carbs (mainly from rice and veggies) and I feel much better. My weight remains the same.
This is a good intro to the potential problems of chronic ketosis [1].
[1] http://freetheanimal.com/2014/02/ketogenic-diets-news.html
That's not a misconception, it is reality. It is amazing how many people on HN really hate science. Diabetics are told to eat juice or candy when their blood sugar is low for a reason.
>The most stable way to supply blood glucose is by eating fat
That is also too slow to be of any use.
Counterpoint: medical science is insanely difficult and expensive, due to individual variations in genetics and lifestyle, and the huge number of variables that it is effectively impossible to completely control for. This leads to research that is tainted by the incentives of those agents that afford the expense, and results that tend to be correlation more often than causation.
That's not to say that we should ignore the science we do have; rather, we shouldn't fall into the trap of assuming we can model biology as precisely as astrophysics. Sometimes the illusion of knowledge is more dangerous than ignorance.
Inflammatory language like this (as well as in https://news.ycombinator.com/item?id=8696794, https://news.ycombinator.com/item?id=8696817, and other comments you've posted) adds to the problem. Assuming you're 100% correct on facts, railing against perceived idiots merely impedes the communication of the facts. It discredits your arguments, and it poisons the discourse. We all need to edit this kind of thing out of the comments we post to HN.
If I do not have glucose on my person then I'm advised to drink anything that is "liquid sugar" - juice, pop, milk (lactose) because it raises the blood sugar quickly.
But you need to consider this is because our bodies are DEFECTIVE. When my blood sugar goes to 30 (been there, done that) I need a blood sugar spike RIGHT NOW. And by right now I mean before I pass out, slip into a coma, and DIE.
So when I am presented with a number so low that I am about to be seriously fucked, and I don't have my tablets with me, I'll eat every fucking carbohydrate in sight because a high blood sugar might kill me in 20+ years, but a low can kill me right now.
Outside of potentially LIFE THREATENING low blood sugar levels diabetics are encouraged to try to stay away from foods that fall into the high glycemic index categroy. This is because they raise blood sugar fast, and then they crash back down just as fast. This is what most of us diabetics refer to as the "Roller Coaster"; and we do not like coasters.
http://www.diabetes.org/food-and-fitness/food/what-can-i-eat...
The really great thing about healthy non-diabetics is your body is really good at self regulation, so your "lows" will likely never go below 70 (e.g. Not dangerous), and even after gorging yourself on an entire pizza and chasing it with a 2 liter bottle of Code Red Mountain Dew your body will still keep your blood sugar maxed at an also healthy 100.
So please don't talk like you understand diabetic science or that it in anyway relates to normal, healthy functioning adults. It is the equivalent of trying to say that someone without cancer should get chemo, because it helps people with cancer. It's not like you are going to pass out and die or possibly have your blood turn into acid and poison you to death (yes this is a real risk for a Type 1 diabetic http://www.diabetes.org/living-with-diabetes/complications/k... http://en.wikipedia.org/wiki/Ketoacidosis)
Me too.
>So please don't talk like you understand diabetic science
Please don't be a condescending prat when what I said is 100% accurate.
Diabetics are allowed to eat sugar, and research indicates that the source of carbs really doesn't matter: http://www.diabetes.org/food-and-fitness/food/what-can-i-eat...
Commonly used and recommended sources of sugar to treat hypoglycemia in diabetics include fruit, soda, juice, candy, sugar, honey and skim milk: http://www.diabetes.org/living-with-diabetes/treatment-and-c...
And the bottom line is the dietary dos and do nots for diabetics just don't apply to healthy people. They are on a different playing field.
Nobody said they did. So, why the angry long rant directed at me exactly?
On the first point,
>>A similar misconception is "I need glucose therefore I should eat sugar" .
>That's not a misconception, it is reality. It is amazing how many people on HN really hate science. Diabetics are told to eat juice or candy when their blood sugar is low for a reason.
Yes, sugar is absolutely necessary for energy. Fat as fuel is pseudo science BS. On the other hand most people consume way more sugar than is necessary and the sugars we take when our blood sugars are low are not the best sources of sugar for a general diet and long term fuel source.
On the second point,
>>The most stable way to supply blood glucose is by eating fat
>That is also too slow to be of any use."
Fats, fiber, and protein are pretty great for fueling stabilized blood sugar since they lower the GI of carbohydrates. While this is not good for low blood sugar, it is great for maintaining stable lower fluctuating blood sugars. So the general advice for a healthy person to eat more fats and less carbs is overall some pretty good as advice as there is very strong evidence that it lowers risk of Type 2 diabetes. As for Type 1, obviously you're just fucked no matter what you do.
Anyway, was not trying to be a "prat", and the TC is wrong on the whole point of
>A similar misconception is "I need glucose therefore I should eat sugar".
Your post came off to me though as the opposite extreme; while not explicitly stated, it seemed to imply that the people saying they should eat/drink high GI food/drinks to raise blood sugars, but really they should probably be eating more lower GI foods.
I would like to see a citation for this. My metabolics text book says that generally fat cannot be made into glucose. Only the glycerol bit can, and that is only a small fraction of the calories in fats.
There may be just a germ of truth in what you say, in that for some people eating large amounts of carbohydrate leads to drastic fluctuations in serum glucose.
When you are eating excessive sugars and carbs like most people today, your body doesn't burn fat. You only use sugars for energy. That's why you have your energy levels constantly up and down.
I have been on ketagonic diet last 3 months. I eat no sugars and less than 50gr carbs. My energy levels are always stable now, lost 20lb. I don't need glucose for energy.
I see it as winter mode vs summer mode:
- If it's is summer there are sugars and carbs. So, your body keep storing as much fat as possible and uses carbs for energy and pushes you to eat as much as you can. Making you feel hungry all the time so you eat more and store more fat.
- if it is winter, there are nothing much to eat, so your body uses fat as energy.
The problem with modern world is that there are just so much food and carbs around us that we are always in summer mode.
The metabolic pathways which do produce glucose are:
1) Eat starches.
2) Eat protein.
Starches are converted directly to glucose. Protein can be converted to glucose by a process called gluconeogensis. This is what happens under either a starvation situation (in which case the protein is supplied from body tissues -- skeletal muscle and eventually organ tissue), or under a ketogenic diet, in which dietary protein could be utilized.
While dietary glucose is apparently not necessary, it's also not a bad thing, provided you're not getting excessive quantities or low-fiber sources which trigger an excessive insulin response.
That said: the typical Western diet provides more than ample glucose and starches, often in an overly refined form. That can trigger lipogenesis, in which excessive glucose is converted to lipids and stored as fat.
These are evolutionary adaptions that let us extract energy efficiently from our environment, maybe yesterday's sensationalist news about our alcohol dehydrogenase efficiency is proof that we should use alcohol for all energy needs.
Now, what i really wonder is; if we see diabetes from abusing the carbohydrate pathways, then what disease comes from abusing the ketone/gluconeogensis pathways ?
[1]: http://en.wikipedia.org/wiki/Gluconeogenesis
You mean the "certain mindset" specifically selected for by the people running the experiment?
There's nothing in there about the results being limited to "people of a certain mindset".
the results highlight the critical role of beliefs about willpower in self-control performance
I don't know how generalizable the results are, and I'm not making claims about its generalizability. I'm simply refuting the notion that it's wholly incompatible with depletion theory. Speaking personally, I would have appreciated some notion of how common any belief whatsoever is for people.
Not about whether increased cognitive load means less self-control on subsequent tasks.
The reality is that science behind it is actually some of the most compelling and thoroughly thought out from the field of behavioral psychology.
Depressing that this is a useful measurement, that is, the level of anger is > 0 on most evenings.
I don't like feeling angry. It's weird.
I can't say anything about your state anymore than I both simultaneously understand and do not understand my own.
My brain and focus is just way better running on fat than on glucose.
Your body runs on sugar not fat. Fat will be transformed into sugar to be used as energy in your body. With that said, it won't create a huge spike in your blood sugar like drinking a soda, and won't cause a giant release of insulin.
Essentially:
vs The TCA is cycle is the actual main energy generating step.Other times fat absolutely is converted to sugar. It all depends on the metabolic needs of the body and one building blocks are available, and what protein "workers" are able to use the ones that are available.
For example, fatty acid synthase converts acetyl coa back to a fatty acid [3].
[0] Glycolysis: http://en.wikipedia.org/wiki/Glycolysis
[1] pyruvate dehydrogenase: http://en.wikipedia.org/wiki/Pyruvate_dehydrogenase
[2] beta oxidation: http://en.wikipedia.org/wiki/Beta_oxidation
[3]: http://en.wikipedia.org/wiki/Fatty_acid_synthase
If you are referring to gluconeogenesis, yes, fat and protein can be converted to glucose but the amounts are fairly negligible. If you eat fat or have fat the body will convert the fat to ketones and use that in the absence of glucose. It's a much more efficient metabolic pathway than going through gluconeogenesis. The vast majority of the body functions quite well on ketones for energy. Most people are not able to metabolize fat at the rates required to avoid fatigue without undergoing ketoadaptation though. It takes anywhere from 3 days to 3 weeks depending on the individual and seems to be correlated with insulin resistance.
this stupid sensationalist articles designed to glorify consumption of junk food are just pathetic and should not be on top of hacker news...
sugar is sucrose - glucose and fructose in a very high energy bond.
apart that honey has a lot of other stuff(bee saliva, pollen) which make the SPEED of absorbtion wayyyyyyyyyyyy different
Why post garbage like that?
>gets in your blood very quick causing insulin spike
Just like honey and fruit and candy do.
>which is bad and bad only
There is no evidence to support that claim. The demonization of "insulin spikes" is for selling a fad diet. It is not based on science.
fruit and honey have a lot of other stuff which slows THE SPEED OF ABSORPTION into blood and does not spike insulin in a wild way like sugar.
try eating spoon of sugar and compare the feel with spoon of honey. it is obvious.
It's not a completely pop-science book, more a translation of his research into an approachable lay-person format. I recommend it.
(edit - link to book: http://www.amazon.com/Willpower-Rediscovering-Greatest-Human... )
[1] http://biology.stackexchange.com/questions/839/how-does-the-...
Then is controlling urge to sip sugary drinks a doomed enterprise?
Coming back to the experiment, shouldn't the will power be benchmarked before testing for effects of glucose? Hypothetically, couldn't I get a study group of weak-willed people and enforce the WSJ article's premise as well as get a bunch of monks and refute it?
This is such a pointless ending sentiment. I realize the irony here too, my comment is pointless transitively but I don't care.
Also, anything that overstimulates the reward system (sugar) will result in weakened willpower.
And while the brain can run on ketone bodies (to a large extent), certain body tissues must have glucose, among them red blood cells.
Don't really see the point going low carb if you're lifting weights and calorie counting since you're replacing muscle glycogen all the time, there's not a lot of excess energy to be stored as fat unless you're eating way above maintenance.