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Flipping the Metabolic Switch: Applying the Health Benefits of Fasting
- mnort 8y agoseems to be becoming more and more “scientifically” clear that brains run better on ketones, and burning fat is cleaner for the body
- mi100hael 8y agoThis does appear to be supported by TFA: > Although the cellular and molecular mechanisms by which IF enhances cognitive and motor performance have not been established, the shift to ketone utilization appears to be one of the key biological mechanisms that prevents age‐related reductions in brain white matter integrity and preserves spatial memory
- jpttsn 8y agoSure, though as your quoted indicate, diet is an inexact science at best. I’d recommend trying interesting diets for yourself, to validate the claimed short run effects.
- avip 8y agoThat's basically the opposite of science.
- satokema 8y agoNo, that is LITERALLY science. You come up with hypotheses and test them. Hypothesis: [Specific diet] will cause no effects on myself, given my unique biochemicalpsycho makeup. Hypothesis: [Specific diet] will cause [list of benefits/mali] for myself, given my unique biochemicalpsycho makeup. etc. Just because it doesn't automatically apply to the population at large does not make it "not science".
- notheguyouthink 8y agoWell I imagine what OP meant was that the testing phase in this "science" is not verifiable/repeatable/etc. Perception is an awful way to perform tests, and is very frequently wrong.
- Erik816 8y agoThat's an interesting point, but I only think it's true under the correct assumptions. If we assume that all bodies are more or less interchangeable, then yes. You'd want to look at large scale, repeatable studies that tie diet into health outcomes, and just follow those. If, however, there is a large amount of variation among human bodies, large scale objective studies may not hold much value for any particular individual. In that case, the proper bounds of the experiment might be one person, or a small group of similar people. In that case, trying various experimental diets and observing the effects is quite scientific, even if not universal.
- pizza 8y ago> So the brain is happily deriving energy from ketones – sure, but why would this be protective against such a variety of brain diseases? > One answer may be energy. Despite their superficial differences, many neurological diseases share one major problem – deficient energy production. During metabolic stress, ketones serve as an alternative energy source to maintain normal brain cell metabolism. In fact, BHB (a major ketone) may be an even more efficient fuel than glucose, providing more energy per unit oxygen used. A ketogenic diet also increases the number of mitochondria, so called “energy factories” in brain cells. A recent study found enhanced expression of genes encoding for mitochondrial enzymes and energy metabolism in the hippocampus, a part of the brain important for learning and memory. Hippocampal cells often degenerate in age-related brain diseases, leading to cognitive dysfunction and memory loss. With increased energy reserve, neurons may be able to ward off disease stressors that would usually exhaust and kill the cell. https://blogs.scientificamerican.com/mind-guest-blog/the-fat-fueled-brain-unnatural-or-advantageous/ https://blogs.scientificamerican.com/mind-guest-blog/the-fat...
- srik 8y agoWait I might have to dig up the sources. But it is generally accepted in the “Keto sphere” that the brain runs on glucose. Even in ketosis the body creates some glucose for this purpose.
- virtuallynathan 8y agoI don't have sources handy, but IIRC the brain will generally to run on about a 60/40 or 70/30 mix of ketones/glucose, but in some experiment they gave people in ketosis a does of insulin to drop their blood sugar to near 0, and they didn't pass out and were otherwise fine.
- Cthulhu_ 8y ago12 hours? Sounds like just skipping breakfast would constitute as intermittent fasting for me. My breakfast is usually pretty light anyway.
- mnort 8y agoit really doesnt take much to implement an intermittent fasting regimen. one easy way to hit it is to simply move to an 8 hour feeding window, eg 10-6 really taking advantage of the time you are sleeping as 'fasting' time, makes the concept of fasting a lot less daunting
- xeromal 8y agoI try to move that around a bit just to avoid feeling hungry when I go to sleep.
- brandall10 8y agoGenerally I've seen 16 hours being the ideal mark for daily fasting. Purely anecdotal, have not gotten a proper BF-test and don't count calories, but it seems since I started constraining my eating to 8 hour blocks a few months ago that I've gotten visibly leaner to the tune of a couple % points. I lift daily and eat fairly clean with 2-3 cheat meals per week.
- hudibras 8y agoYou're exactly right. Just skip breakfast and don't eat snacks after dinner and you'll be at 16 hours easy. Try it for a week and see how you feel. I've been IF'ing for 15 months now and it's great. Lost 20 pounds without even trying and have more energy during the day.
- DanielBMarkham 8y agoLike many programmers, especially us older folks, I've struggled with my weight my entire life. Three weeks ago I went on a ketogenic diet. This week I've added intermittent fasting, only eating between noon and six. After the "keto flu" period ended, it's been quite enjoyable. The IF comes quite naturally and is painless. I'm not one to spot diet trends, but my intuition says that keto/IF will be a big thing over the next few years. It feels like it's reached critical mass.
- mnort 8y agoI'd be curious to hear more about what you experienced during your keto flu
- DanielBMarkham 8y agoThere was a bunch of little stuff. I don't think it was as bad as the flu, but it was somewhat uncomfortable. The initial symptom was wanting to eat all of the time, even if I wasn't hungry. My brain was convinced that I had to spend huge chunks of my time chewing on something flavorful. So I sliced off some very flavorful cheese and nibbled little tiny pieces during the morning. That seemed to work. Note that I avoided all artificial sweeteners. There's some danger there that I felt I should avoid. Eating a bunch of cheese leads to constipation. Some fiber every morning fixed that. There were a few other things. My energy level dropped right off, then came back. Now I have much more energy than when I started. I had a little bit of brain fog, but it was manageable. The biggest thing I've found about keto is that my personality changes. I am much more relaxed and sedate than I used to be -- more on an even keel. That's not necessarily a benefit. It was just unexpected. ADD: The crazy thing about keto, as opposed to just IF, is that you have to be really OCD about what you eat. Manufacturers sneak carbs into everything. A food journal was critical for me -- and it was something I felt I didn't have to do, since I already knew so much about nutrition! Good thing my SO talked me into doing one.
- toyg 8y ago> Manufacturers sneak carbs into everything. It's insane. You go buy beans, and there's rice flour in it. You buy salmon, and there's sugar in it. It's beyond ridiculous, and explains so much about rising levels of obesity. Anything even vaguely processed has a lot of unnecessary carbs added, for one reason or another.
- blunte 8y agoOne thing you have to pay attention to while aiming for a 12+ hour gap is that you don't accidentally consume calories in drinks, especially from sugar... so no milk, honey, or sugar in your tea or coffee. A little sugar calories will prevent the switch flip, leaving you in a starvation state where you feel awful and eat your own muscles.
- mnort 8y agoFolks in the keto/fasting space seem to present salted water as a good option here
- not_a_moth 8y agoFyi, I've heard health professionals, like Rhonda Patrick mentioned here, say that coffee and tea will still cause your digestive system to secrete enzymes that can undo IF effects, that you should only drink water during the no-eat window. I've given up my morning caffeine to do it.
- mustuhfa 8y agoDo you mean during the fasting period or when you are out of the fasting period? Can you consume sugar when you are out of the fasting period?
- amelius 8y agoSounds great, but is this compatible with: - bodybuilding - 20 miles daily commute by bicycle - intellectually intense work, e.g. hackathons ?
- rhombocombus 8y agoIt might be, anecdotally I know of a few high performing athletes who are now keto all the way. That said, it is utterly incompatible with my desire for milkshakes and candy bars, both of which are things I crave at the end of an intense bike ride.
- deleted 8y ago[deleted]
- mi100hael 8y agoYes, you just need to account for that in your total caloric intake. Your re-feeds are going to need to be bigger.
- ryanworl 8y agoYes. Your liver glycogen and muscle glycogen will be fine. Your body can convert protein to glucose when it is needed and use ketones for everything else.
- haraldooo 8y agoIt really isn't a problem once you're adapted which takes a few days normally (my experience). These guys seem to have no problems with their physical strength on a ketogenic diet: http://www.fatchancerow.org/ http://www.fatchancerow.org/ - so if this isn't fake (which I don't think) most daily energy demands should be satisfied.
- andreygrehov 8y agoFor anyone interested to read about fasting, there is an amazing book written by Arnold Ehret, Mucusless Diet Healing System [1], published in 1922. Interesting fact, the book is from Steve Jobs' reading list. [1] https://www.amazon.com/Mucusless-Diet-Healing-System-Scientific/dp/1884772005 https://www.amazon.com/Mucusless-Diet-Healing-System-Scienti...
- tachion 8y agoI would be cautious to make health related reading recommendations where the book comes from 1922 and was on a reading list of a man who was rejecting science based medication for his serious sickness until it was too late.
- andreygrehov 8y agoGood point. The problem is that Steve Jobs ignored Ehret’s concept of a “transition diet,” and became taken with the idea of being a fruit-only eater right away.
- stevehawk 8y agoI thought the problem was that he ignored getting treated for cancer and died?
- andreygrehov 8y agoNo way?! How confident are you? Anyways, I mentioned Steve Jobs just as an interesting fact. Nothing more, nothing less. I don't personally believe that anybody should be cautious recommending a book. It's a whole separate topic, but in short, can't help one if he's stupid enough to try whatever is on the internet, but I'm glad to share useful information with the smarter one. Otherwise there is no neither progress nor evolution.
- fmihaila 8y ago> No way?! How confident are you? Not just confident, but certain. From Jobs's authorized biography: To the horror of his friends and wife, Jobs decided not to have surgery to remove the tumor, which was the only accepted medical approach. "I really didn't want them to open up my body, so I tried to see if a few other things would work," he told me years later with a hint of regret. Specifically, he kept to a strict vegan diet, with large quantities of fresh carrot and fruit juices. To that regimen he added acupuncture, a variety of herbal remedies, and occasionally a few other treatments he found on the Internet or by consulting people around the country, including a psychic. For a while he was under the sway of a doctor who operated a natural healing clinic in southern California that stressed the use of organic herbs, juice fasts, frequent bowel cleansings, hydrotherapy, and the expression of all negative feelings. [...] His friends repeatedly urged him to have surgery and chemotherapy. "Steve talked to me when he was trying to cure himself by eating horseshit and horseshit roots, and I told him he was crazy," Grove recalled. Levinson said that he "pleaded every day" with Jobs and found it "enormously frustrating that I just couldn't connect with him." The fights almost ruined their friendship. "That's not how cancer works," Levinson insisted when Jobs discussed his diet treatments. "You cannot solve this without surgery and blasting it with toxic chemicals." Even the diet doctor Dean Ornish, a pioneer in alternative and nutritional methods of treating diseases, took a long walk with Jobs and insisted that sometimes traditional methods were the right option. "You really need surgery," Ornish told him. Jobs's obstinacy lasted for nine months after his October 2003 diagnosis. [...] In july 2004 a CAT scan showed that the tumor had grown and possibly spread. It forced him to face reality."
- joshe 8y agoIt would be cool to see measurements of people on Survivor or all the alone in wild shows. Like blood glucose, ketones, movement tracking, and sleep. Maybe even a few IQ and strength tests. There's all this great documentary monitoring and doctors already on site. I assume that academic ethic review boards would never allow a researcher to participate, but it would be great if the shows shared it. Maybe the individual competitors could. I wish there was some middle ground between self tracking and big expensive studies that don't really change anything.
- lhuser123 8y ago> The metabolic switch usually occurs between 12 and 36 hours after cessation of food consumption, depending on the liver glycogen content at the beginning of the fast, and on the amount of the individual's energy expenditure/exercise during the fast. I guess that since my breakfast time is around 8 am, then should stop food intake before 8 pm. The earlier the better. And some light exercise during that period, even better. Let’s do this!.
- pmccarren 8y agoI highly recommend looking into the work of Dr. Rhonda Patrick, Ph.D. She has extensive material explaining the science behind IF, and many other topics relating to bio pathways and aging. https://www.youtube.com/watch?v=m6KClPkotxM https://www.youtube.com/watch?v=m6KClPkotxM https://www.foundmyfitness.com/ https://www.foundmyfitness.com/
- nissarup 8y agoAnd broccoli sprouts! Don't forget the broccoli sprouts! Jesting aside. She is cool, talks very fast and deliver an awful lot of information in a short time.
- pmccarren 8y agoHah gotta get that sulforaphane! Though I do agree - her podcasts can sometimes be a bit of an information overload for those who aren't biomed folk. However in my opinion, her youtube channel[1] is significantly easier to follow as there are often animations and more lengthly explanations. [1] https://www.youtube.com/foundmyfitness https://www.youtube.com/foundmyfitness
- evo_9 8y agoAnd awesome Krill-Oil, too. ;) Also provided a DNA health check if you want to link your 23andMe account.
- projectramo 8y agoWhat if you have to exercise? Should one exercise while fasting? Or to put it another way, if you only eat between 10am and 6pm (let's say), what is the best time to exercise? Before work or after work?
- 121watts 8y agoThat depends on the type of exercise you're doing.
- projectramo 8y agox fit?
- sasper 8y agoYou adapt pretty quickly to however you want to setup your fast. The typical recommendation is to workout fasted at the end of your fast, so you can eat afterwards. Have something light to start, then your first full meal shortly afterwards. I do heavy PPL lifting program 6 days a week and have been doing IF for 3 months. The first 2 weeks were mentally tough at the gym, but after that, the gym really helps me finish off the last couple of hours of my fast and I haven't noticed a negative change in energy levels or strength.
- throwaway413 8y agoFitting to see this during this month, as it is currently the holy month of Ramandan for Muslims, who fast from sunrise to sunset for 30 days.
- Someone1234 8y agoI wonder if any studies have looked at if Muslims who participate in Ramadan receive any measurable health benefits. Even if Ramadan is only one month of the year, that could still potentially show some benefits if there are any over a whole life time.
- Melchizedek 8y agoThe Muslim way of fasting is likely not healthy (or at least not optimally healthy). Food intake should fit the body's circadian rhythm: eat during light hours, fast when it's dark. This is pretty well established.
- throwaway413 8y agoFor perspective’s sake, keep in mind that this practice was established in the desert circa ~600AD and many communities were already much more active during later evening and earlier morning hours. So not exactly the same lifestyle as the modern American person.
- baud147258 8y agoWell, perhaps it's good for the metabolism of my muslim colleague, but right now his productivity is way down. Also I don't the ramandan fasting is particularly good since muslims usually eat a lot during the night to compensate.
- jbm 8y agoI generally don’t have a problem at work (Ramadan + Keto). Then again I don’t get up at 2 AM to eat. (Generally have a 18:6 fasting to eating cycle) Can you share how you are measuring changes in his productivity? I find that, in general, to be fairly difficult to measure, let alone find trends in small time intervals (like a week)
- aviv 8y agoLol. For years I talk about fasting here on HN and get downvoted to oblivion. Intermittent fasting is what they now say is healthy because it means you're still consuming food so they still make money. A far better alternative and a cure to many many "diseases" (yes, cure, I said it) is a prolonged water fast (10 to 40 days), and/or a dry fast (no food no water) for 2 to 10 days.
- madeuptempacct 8y agoCan you back this up with research?
- kaslai 8y agoI've had serious weight issues for my whole life, primarily due to my love of chocolate. As I approached 400 pounds, I took a hard look at myself and decided to make a change. For the past month (29 days now) I've been doing alternate-day fasting* where I eat about 2000-2500kcal on eat days and cap myself at about 100kcal of half-and-half with coffee on fast days (gotta get that joe). While a lot of it is no doubt non-lipid mass (glycogen and such), I just passed 30 pounds of mass lost yesterday. After the initial drop from glycogen loss, I've been averaging 0.4-ish pounds a day of mass loss. A few things I've noticed: What I eat doesn't really affect long-term weight loss. Carbs will cause my weight to rise, but it's definitely just due to the storage and retention of glycogen and water, as I get right back on track with my projections 2-3 days later. However, if I eat carbs and fast the next day, I will get serious hunger pangs. If I eat a mostly keto diet, then I can pass between eat days and fast days with no trouble at all. My biggest take-away though is that fasting has helped me practice self-denial to the point where I can handle my sweet tooth very easily now. The difference in apparent willpower is so immense that I can hardly believe it myself. I definitely suggest that anyone who has self-control issues with regards to food go on a week of alternate day fasting. Additionally, a fast day is a great way to counter out a day of eating to excess. When I lose my weight, I'll still keep fasting as an option, because it's a remarkably powerful tool. * It's actually 3 days of fasting, 4 days of eating a week. I do social eating on Fridays and Sundays, so I keep those as fixed eat days, so I just fast on Sat/Mon/Wed, eat on Fri/Sun/Tue/Thu.
- rhema 8y agoWant to see something crazy? This guy has a huge YouTube following and preaches (through obscene language) long fast https://www.youtube.com/channel/UC_yUeH8TsG5pxqvkOxBtsFA https://www.youtube.com/channel/UC_yUeH8TsG5pxqvkOxBtsFA. He experiments on himself and "coaches" people on dieting. Along with the posh attitudes of fad diets can also come extremism. Do go too crazy with fasting!
- salimmadjd 8y agoAbout 4 years ago I started changing my diet. I drastically reduced foods with sugar and carbs and gradually shifted to a one main meal a day regiment. I eat my main meal (4 eggs, half an avacodo, cucumbers, tomatoes and bell peppers salad with some feta cheese) around 12-2:00. I usually have an apple later. Some weeks I fast for 44-48 hours. I workout at a boxing gym twice a week (about 1.5 hours of a strenuous workout). I’ve been going to the same gym for 10 years, but after changing my diet my stamina increased, sometimes I feel like I can be there all day. The 44-48 hour fasting are interesting and are hard. Not because of feeling hungry(you’re but for me it’s more mental, the thought of all the food I should eat the next day), but because of other factors. The second night your brain is very alert, almost feeling like consuming a lot of caffeine or other stimuli. So if you wake up middle of the night it’s hard to fall asleep again. In the morning, I’m very hyper again as if I had consumed a lot of caffeine and if I drink tea or rarely coffee just before the end of my fast the effects are greatly magnified. Your brain races like mad. I feel like I have an improved cognitive ability, but I’ve not tested that in any form so it could just be a reflection of being hyper. That said I’ve gotten physically stronger, since my diet change and my fasting. I end my boxing workout with some weights and now I often get comments how strong I am for my body size. And I know I’ve gotten stronger, because the increased reps and weights I can do. There was some research on fasting and how your muscles become more efficient, so I’m not sure if that’s playing a factor or my increased stamina has allowed me to workout longer and that resulted in increased strength. The other factor helping me here I think it’s reduced inflammation. It feels like my muscles recover faster and I have less inflammation problems because of my diet. Some interesting anecdotes. One of the guys who works for the gym commented at my transformation and said I look like a “jock” now and asked details of my diet. My former boxing instructor who initially told me for best recovery I needed to eat after a hard workout instead of fasting, now has changed his diet as well. So there is something to all these and I’m never going back, but I think we’re still far from knowing the longer term effects of it and also learning about any genetic variability. But I recommend everyone trying it for themselves, it’s easy after the first 7-10 days.
- JoshMnem 8y agoI've been experimenting with water fasting, intermittent fasting, and calorie restriction for over two years with good results. I gradually went from an "obese" BMI to normal, and reduced the symptoms of some medical conditions, especially after 3-5 day water fasts. I think that if one is going to restrict calories, it's a good idea to eat a high-nutrient diet. Mine is mostly vegan + fish, and based on vegetables, legumes, nuts, seeds, and fruits. Almost zero sugar, low salt, no flour, and not a lot of grains. A saying that helped me stay focused is, "Food is not a recreational drug."
- wmeredith 8y agoPlease note: dry fasting is incredibly dangerous and one will struggle to find non-crackpot sources that say humans should attempt it for any reason. Healthy people can survive a month or more without food. Without food AND water they last less than a handful of days.
- jiscariot 8y agoI've been doing intermittent fasting for about a year--it seems to work for me because I struggle with controlling portion sizes. Mon/Wed of every week I limit caloric intake severely--I skip all meals and snack on olives, pickles, maybe a small amount of avacado in the evening along with a couple of La Croix. Not sure why olives/pickles, other than I wanted to keep the fasting foods keto-friendly. Other than that, I used to chew a lot of gum during fasting, but have since stopped because I'm not sure what exactly "sugar alcohol" is doing to my body. It has worked out well for me. I started at 230 in June and hit my baseline of low 190's in mid-November. I've been there since doing the 2-day fast. It is not too bad so long as you can stay busy, although it does really affect my mood on those fast days. It has helped my mountain/road biking immensely. Just wanted to share my experiences...if anyone has other recommendations for fasting days, please share.
- jcousins 8y agoI had mood issues with one meal a day regime, I managed to resolve it with Tryptophan supplementation (an amino acid known to act as an antidepressant, avoid if taking SSRIs) for two months and upping my cruciferous vegetable intake significantly (half a kilo a day). This was after reading The Diet Cure by Dr. Julia Ross. I have since stopped taking the Tryptophan and mood remains stable.
- abakker 8y agoHow has it effected your biking? More endurance? Peak Power? or just being lighter?
- jiscariot 8y agoI think it is just being lighter, but the difference in endurance/recovery from hills, etc is pretty significant.
- thinkling 8y agoThe summary mentions that fasting is used to deplete glycogen stored in the liver. Doesn't moderate aerobic endurance exercise do the same thing? If you regularly go on long bike rides, will you get the same benefit?
- mirko22 8y agoRobert Lusting has cery intersting book on this, and more specifically the influence of fructose sugar in diet. https://m.youtube.com/watch?v=ceFyF9px20Y https://m.youtube.com/watch?v=ceFyF9px20Y
- virtuallynathan 8y agoI can 100% vouch for this, roughly 90 days ago I implemented: * 16h+ intermittent fasting * increased exercise (>600kcal Apple Watch active kcal) * caloric restriction (average of 450kcal deficit). I lost 20lbs in 90 days (5ft5in 145 -> 125). I've since gone to a full ketogenic diet as an n=1 experiment. I find the research on this lacking, but fascinating -- its been a very educational experience. Based on the many papers I've read, and talks I've listened to, it seems like society's current ailments of obesity, diabetes, and heart disease (and maybe Alzheimers) tie back to excess carbohydrate consumption leading to hyperinsulinemia. Re: this paper -- they cite that "Mice fed a high‐fat diet ad libitum develop obesity, elevated plasma glucose, insulin and leptin levels, and impaired glucose tolerance" However, reading the source for that, the diet of those mice was: "18% protein, 61% fat, 21% carbohydrates" -- probably still too many carbs.
- wink 8y agoNot eating for 16h-18h is not intermittent fasting for me, but how I've lived huge parts of my life. Lunch at noon or soon after, dinner before 8, nothing else. Didn't notice anything remotely pointing towards losing weight to a reasonable weight.
- DoofusOfDeath 8y agoSo do we know enough at this point to confidently recommend a fasting schedule that ought to be safe and worthwhile for most adults? Or are we still bathing in incomplete/flawed studies, bad reporting, and the promotion of diet-fads? This sounds like something I'd like to try if the reported upsides are real, but I don't have a lot of time to filter out junk science.
- virtuallynathan 8y agoIt's a pretty easy n=1 trial -- stop eating at 8pm, and eat again at noon. Maybe exercise in the morning to accelerate the glycogen depletion. Try it for a month, report back! There are many studies on this, the literature seems to suggest it works, and I can say it worked for me.
- krupan 8y agoAnyone read The Hacker's Diet? http://www.fourmilab.ch/hackdiet/ http://www.fourmilab.ch/hackdiet/ I find it interesting that he mentioned as kind of a side note that he only eats one meal a day. A man ahead of his time :-)
- mythrwy 8y agoI'm not at all overweight and personally don't see what this fasting thing is about. If I even skip breakfast forget hard thinking or strenuous effort.
- t0mbstone 8y agoFasting is great and all if you don't have to perform mental tasks throughout the day. When I am on vacation and have time off of work to just relax, I regularly forget to eat, and I barely even notice. When I'm at work and doing programming, however, even the slightest reduction in my caloric intake schedule results in me feeling lightheaded and "foggy". My ability to code effectively plummets, and I also find myself unintentionally being more irritable towards co-workers. As such, my job as a professional programmer basically requires me to eat regularly. Fasting is not an option for me, unfortunately.
- tqkxzugoaupvwqr 8y agoYou could fast before and after work. Eat all the calories you need in your 9 hour window, fast in the remaining hours.
- t0mbstone 8y agoOh, well, that's basically what I already do. I don't eat at night time (obviously). There's a reason why the first meal of the day is called "break fast"...
- kvhdude 8y agoas always there is news to the contrary indicating harmful effects : https://www.medicalnewstoday.com/articles/321864.php https://www.medicalnewstoday.com/articles/321864.php