7 ms·

>> 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 ex

• maerF0x0 12y ago
  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.
  • Florin_Andrei 12y ago
    Stable, maybe - but very slow for sure. 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.
    • maerF0x0 12y ago
      Several studies have shown that endurance is equal w/ fat as the fuel. You do have to spend 4 or so weeks adapting though. 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-athletes-use-fat-or-carbohydrate-as-fuel-631# http://www.pponline.co.uk/encyc/sports-nutrition-should-athl...
      • sekm 12y ago
        Yep - this guy does some great stuff on fat too: http://www.bengreenfieldfitness.com/2013/05/low-carb-triathlon-training/ http://www.bengreenfieldfitness.com/2013/05/low-carb-triathl...
      • justsomedood 12y ago
        That's a really interesting article. 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
        • Florin_Andrei 12y ago
          > bonk There's only one thing that gets you out of it quickly - and that's a shovel full of carbs.
    • fsargent 12y ago
      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.
      • sysk 12y ago
        Same experience here. First few days were a bit painful but afterwards I felt my energy level was higher on a fat based diet (Ketogenic diet).
    • rsync 12y ago
      "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.
      • nly 12y ago
        > eating cheese pizza slices Well cheese is a good mix of protein and fat, and the base is full of carbs
      • deciplex 12y ago
        > 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.
    • electromagnetic 12y ago
      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.
  • jimjimjim 12y ago
    Not if you need glucose delivered quickly (i.e to help with the task at hand). http://www.bbc.co.uk/programmes/b03t8r4h http://www.bbc.co.uk/programmes/b03t8r4h The body can't easily/quickly convert fat into glucose.
    • dredmorbius 12y ago
      The body cannot convert fat into glucose at all.
      • coldtea 12y ago
        You'd be surprised: """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."""
        • dredmorbius 12y ago
          What are the rates of this pathway? Minimum daily glucose requirements are on the order of 100g, possibly higher. If this pathway cannot sustain that delivery rate, it's not significant.
          • coldtea 12y ago
            Sure, and I didn't say otherwise. 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.
            • dredmorbius 12y ago
              Sorry, but you're apparently misreading my tone. 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 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.
  • chiph 12y ago
    This works for the Inuit. But they also have genetic adaptations that help with a diet that is laden with fat. http://anthro.palomar.edu/adapt/adapt_5.htm http://anthro.palomar.edu/adapt/adapt_5.htm
    • Evgeny 12y ago
      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.
    • fasteo 12y ago
      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. [1] http://freetheanimal.com/2014/03/disrupting-carbs-prebiotics.html http://freetheanimal.com/2014/03/disrupting-carbs-prebiotics...
  • raverbashing 12y ago
    No, the best way to supply blood glucose is by eating: Glucose, or something that's easily converted to it, like starches, which are a glucose polymer note: Saccharose, which is Glucose + Fructose can help with that as well
  • msluyter 12y ago
    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. So there's one anecdote for you.
    • imanaccount247 12y ago
      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?
      • bcheung 12y ago
        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. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2367001/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2367001/
        • imanaccount247 12y ago
          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".
    • xorcist 12y ago
      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?
      • cle 12y ago
  • daniel-cussen 12y ago
    No, the best way to supply glucose is eating glucose. I used to do this.
  • imanaccount247 12y ago
    >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 That is also too slow to be of any use.
    • lukifer 12y ago
      > 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.
      • imanaccount247 12y ago
        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.
    • bcheung 12y ago
      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.
    • dang 12y ago
      > 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=8696794, https://news.ycombinator.com/item?id=8696817 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.
  • wavegeek 12y ago
    > 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.
    • aytekin 12y ago
      He means Ketones. 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.
  • dredmorbius 12y ago
    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.
    • BasLeijdekkers 12y ago
      It seems there is a pathway that converts lipids to glucose: http://www.ncbi.nlm.nih.gov/pubmed/22314896 http://www.ncbi.nlm.nih.gov/pubmed/22314896
      • dredmorbius 12y ago
        News to me, thanks.
      • fasteo 12y ago
        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.
        • undersuit 12y ago
          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.
• siglesias 12y ago
  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.
  • pdpi 12y ago
    > One could argue that this study is showcasing a strategy for people of a certain mindset to improve their willpower; 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".
    • siglesias 12y ago
      The article literally states: 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.
• b_emery 12y ago
  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.
• coldtea 12y ago
  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.
• iQuercus 12y ago
  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.
  • ada1981 12y ago
    Perhaps I had low glucose when making the post and impulsively did so vs. better fact checking.