5 ms·

I think that's the premise behind keto.

TeMPOraL 8y ago
Yes, but that works on the idea that providing no glucose to the body will make it switch to fat instead. So it's not really diet "controlling" which fuel source to use, just body using the best fuel source available, and switching to the next one when the previous one runs out.
- therein 8y ago
  I've followed a ketogenic diet for over over six months and lost 60lbs during that time while eating a disgusting amount of protein and fat. I never felt more clear-minded than I did during the diet. Colors were enhanced and I felt like I had unlimited energy. No ups and downs in mood during the day, no "unknown crash" at the end of the day. Of course this is after the initial crash that you experience until your body figures out it needs to switch fuel. It made me realize, often when we say we are hungry and we are craving something, it's not that we are hungry, it's that we are craving carbs.
  - TeMPOraL 8y ago
    I've been on a ketogenic diet for ~half a year a few years ago. I did lose weight and didn't experience any significant negatives, though I also didn't notice any positives - no extra mind clarity or color perception or whatever. But for the main goal - losing weight - it worked for me well.
    - therein 8y ago
      Did you make sure you were in ketosis all throughout by using ketone strips? Back when I did it, I had two friends that did it with me. One of them got cognitive benefits like I did while the other did not. It might be that we were deficient in or sensitive to something else. In fact the energy was so boundless at the 2-week mark that we actually had a hard time falling asleep at night.
      - TeMPOraL 8y ago
        I didn't. I didn't even bother looking up where I could find those strips. I just cut carbs down to almost zero, eating carbs-free + controlled, small amounts of carbs. I paid attention to stay under 20g of carbs per day. I was never really sure I was in full ketosis - I just started to follow the diet, noticed some changes in urine that may or may not indicate ketosis (I definitely didn't have the intensive smell some people describe), and tracked my weight daily. It worked well over couple of months. Actually, I found the chart I made then: https://www.dropbox.com/s/vdlgazsfjjbqkox/weight-2012.png?dl=0 https://www.dropbox.com/s/vdlgazsfjjbqkox/weight-2012.png?dl... (Measurements are blue, running average (of AFAIR a week) is green. I used the running average as an indicator of progress, to eliminate measurement noise / daily variations.) That ~8-10kg drop in 3 months is when I was on ketogenic diet. I carried it a bit longer, then I guess at some point I just decided I miss pizza too much. One permanent change this caused though, that I have to this day, is that I switched from sugar to artificial sweeteners in my tea/coffee, and always opt for sugarfree coke/pepsi instead of the regular one.
        will_brown 8y ago
        >I was never really sure I was in full ketosis Following your conversation I have a wild guess...you likely were not exercising and therein likely was. First, I’ve never meet anyone who did some form of working out/exercising who couldn’t tell if they were in ketosis (good or bad). If I am right, this may also explain the feeling of mental clarity therein experiences that you didn’t. Glucose is fuel for the brain, but fat isn’t...ketones are which are a by product of fat burning, so the more fat burning/ketones the more fuel for the brain. Interesting if you both chime in on my theory.
        TeMPOraL 8y ago
        From my end: I wasn't a total couch potato, but I also definitely wasn't doing any kind of regular exercise.
        therein 8y ago
        From my end your guess adds up. I did exercise, and my body's transition to increased affinity for ketone utilization was definitely noticeable during my workouts. And indeed the mental clarity and color enhancement was more pronounced following a workout, however unlike on a normal diet, these state stayed with me all day rather than only for a few hours. > Glucose is fuel for the brain, but fat isn’t...ketones are which are a by product of fat burning, so the more fat burning/ketones the more fuel for the brain. That definitely makes sense to me and would even to a certain extent explain the difference between individual experiences with ketogenic diet.
  - dorfsmay 8y ago
    > it's not that we are hungry, it's that we are craving carbs. No. You are hungry, not necessarily for carb or protein or fat, you're just hungry. If you wait long enough, your body will switch to burn body fat.
    - therein 8y ago
      What I meant by that was this: Even after knowing that my body has switched to primarily using ketones via Ketone Measurement Strips used on urine daily, I would find myself wanting to eat something, but once I realized all I had at home that I could eat was food full of fat and protein but not carbs, my craving would disappear or I would become disinterested. And even after eating, I could still feel that it didn't hit the right spot at satisfying my cravings. I would be really full, and really full of energy-dense food but I would still be dreaming of a slice of bread or even a sip of lemonade next to whatever dish I am eating. I realized what I craved wasn't food but that spike in blood sugar.
  - DanBC 8y ago
    Sure, but this is literally what some people using homeopathy or reiki or crystal healing say.
- will_brown 8y ago
  >Yes, but that works on the idea that providing no glucose to the body will make it switch to fat instead. So it's not really diet "controlling" which fuel source to use I think there is just a difference in the use of "controlling" here. Fat/Glucose will always be used jointly as energy, but the idea is to "control" which is the primary fuel source. A Ketogenic diet or ketosis is part of that, still giving you a fair reading I can understand how you conclude that is not "control", though I would argue it is because I am controlling my fuel source, but to your point I am not eating whatever I want (carb/sugar heavy diet) and controlling my primary fuel source like a light switch. Separate and apart from the diet, there are other things you can do to "control" or "train" your body to burn fat as the primary fuel source. Again keto is a large part of it, but lets assume I am in ketosis and about to go for one of my runs...in short, aerobic or anaerobic. Is my body going to go for the fat or is it going to go for the available glucose which is the preferred energy source for anaerobic exercise? Also, in anaerobic exercise the muscles produce lactic acid as a by product and as anaerobic exercise can only be maintained for a short period of time, when its over and the body is recovering the lactic acid goes to the liver and is converted into glucose, of course that raises the blood glucose level which in turn may encourage the body to use as the primary fuel source. Keeping my run aerobic I am "controlling" the primary fuel source and burning fat, both in the short term (same run) and long term (over periods of time) I am training my body to be pushed harder and harder while maintaining my aerobic threshold increases.
  - stefan_ 8y ago
    Deriving energy from fat is strictly less oxygen efficient than from glycogen; oxygen supply of course being the main limiter of aerobic endurance. This is why as you increase intensity towards VO2max the balance of fat versus glycogen use shifts dramatically in favor of glycogen. So training in a glycogen depleted state (back then we called this bonking) is bad news if you want to increase your aerobic threshold, since the kind of training that has been shown most effective in causing the required adaptations involves repeated maximal efforts. The only training effect you can hope for is nudging your body towards using more fat at lower levels of exertion, thereby saving valuable glycogen. This isn't very relevant for most running events which are typically done at a consistently high VO2max percentage, but beneficial for say cycling races where you have low intensity (riding in the slipstream on the flat) mixed with very high intensity (up a steep grade).

Yes, but that works on the idea that providing no glucose to the body will make it switch to fat instead. So it's not really diet "controlling" which fuel source to use, just body using the best fuel source available, and switching to the next one when the previous one runs out.

therein 8y ago
I've followed a ketogenic diet for over over six months and lost 60lbs during that time while eating a disgusting amount of protein and fat. I never felt more clear-minded than I did during the diet. Colors were enhanced and I felt like I had unlimited energy. No ups and downs in mood during the day, no "unknown crash" at the end of the day. Of course this is after the initial crash that you experience until your body figures out it needs to switch fuel. It made me realize, often when we say we are hungry and we are craving something, it's not that we are hungry, it's that we are craving carbs.
- TeMPOraL 8y ago
  I've been on a ketogenic diet for ~half a year a few years ago. I did lose weight and didn't experience any significant negatives, though I also didn't notice any positives - no extra mind clarity or color perception or whatever. But for the main goal - losing weight - it worked for me well.
  - therein 8y ago
    Did you make sure you were in ketosis all throughout by using ketone strips? Back when I did it, I had two friends that did it with me. One of them got cognitive benefits like I did while the other did not. It might be that we were deficient in or sensitive to something else. In fact the energy was so boundless at the 2-week mark that we actually had a hard time falling asleep at night.
    - TeMPOraL 8y ago
      I didn't. I didn't even bother looking up where I could find those strips. I just cut carbs down to almost zero, eating carbs-free + controlled, small amounts of carbs. I paid attention to stay under 20g of carbs per day. I was never really sure I was in full ketosis - I just started to follow the diet, noticed some changes in urine that may or may not indicate ketosis (I definitely didn't have the intensive smell some people describe), and tracked my weight daily. It worked well over couple of months. Actually, I found the chart I made then: https://www.dropbox.com/s/vdlgazsfjjbqkox/weight-2012.png?dl=0 https://www.dropbox.com/s/vdlgazsfjjbqkox/weight-2012.png?dl... (Measurements are blue, running average (of AFAIR a week) is green. I used the running average as an indicator of progress, to eliminate measurement noise / daily variations.) That ~8-10kg drop in 3 months is when I was on ketogenic diet. I carried it a bit longer, then I guess at some point I just decided I miss pizza too much. One permanent change this caused though, that I have to this day, is that I switched from sugar to artificial sweeteners in my tea/coffee, and always opt for sugarfree coke/pepsi instead of the regular one.
      - will_brown 8y ago
        >I was never really sure I was in full ketosis Following your conversation I have a wild guess...you likely were not exercising and therein likely was. First, I’ve never meet anyone who did some form of working out/exercising who couldn’t tell if they were in ketosis (good or bad). If I am right, this may also explain the feeling of mental clarity therein experiences that you didn’t. Glucose is fuel for the brain, but fat isn’t...ketones are which are a by product of fat burning, so the more fat burning/ketones the more fuel for the brain. Interesting if you both chime in on my theory.
        TeMPOraL 8y ago
        From my end: I wasn't a total couch potato, but I also definitely wasn't doing any kind of regular exercise.
        therein 8y ago
        From my end your guess adds up. I did exercise, and my body's transition to increased affinity for ketone utilization was definitely noticeable during my workouts. And indeed the mental clarity and color enhancement was more pronounced following a workout, however unlike on a normal diet, these state stayed with me all day rather than only for a few hours. > Glucose is fuel for the brain, but fat isn’t...ketones are which are a by product of fat burning, so the more fat burning/ketones the more fuel for the brain. That definitely makes sense to me and would even to a certain extent explain the difference between individual experiences with ketogenic diet.
- dorfsmay 8y ago
  > it's not that we are hungry, it's that we are craving carbs. No. You are hungry, not necessarily for carb or protein or fat, you're just hungry. If you wait long enough, your body will switch to burn body fat.
  - therein 8y ago
    What I meant by that was this: Even after knowing that my body has switched to primarily using ketones via Ketone Measurement Strips used on urine daily, I would find myself wanting to eat something, but once I realized all I had at home that I could eat was food full of fat and protein but not carbs, my craving would disappear or I would become disinterested. And even after eating, I could still feel that it didn't hit the right spot at satisfying my cravings. I would be really full, and really full of energy-dense food but I would still be dreaming of a slice of bread or even a sip of lemonade next to whatever dish I am eating. I realized what I craved wasn't food but that spike in blood sugar.
- DanBC 8y ago
  Sure, but this is literally what some people using homeopathy or reiki or crystal healing say.
will_brown 8y ago
>Yes, but that works on the idea that providing no glucose to the body will make it switch to fat instead. So it's not really diet "controlling" which fuel source to use I think there is just a difference in the use of "controlling" here. Fat/Glucose will always be used jointly as energy, but the idea is to "control" which is the primary fuel source. A Ketogenic diet or ketosis is part of that, still giving you a fair reading I can understand how you conclude that is not "control", though I would argue it is because I am controlling my fuel source, but to your point I am not eating whatever I want (carb/sugar heavy diet) and controlling my primary fuel source like a light switch. Separate and apart from the diet, there are other things you can do to "control" or "train" your body to burn fat as the primary fuel source. Again keto is a large part of it, but lets assume I am in ketosis and about to go for one of my runs...in short, aerobic or anaerobic. Is my body going to go for the fat or is it going to go for the available glucose which is the preferred energy source for anaerobic exercise? Also, in anaerobic exercise the muscles produce lactic acid as a by product and as anaerobic exercise can only be maintained for a short period of time, when its over and the body is recovering the lactic acid goes to the liver and is converted into glucose, of course that raises the blood glucose level which in turn may encourage the body to use as the primary fuel source. Keeping my run aerobic I am "controlling" the primary fuel source and burning fat, both in the short term (same run) and long term (over periods of time) I am training my body to be pushed harder and harder while maintaining my aerobic threshold increases.
- stefan_ 8y ago
  Deriving energy from fat is strictly less oxygen efficient than from glycogen; oxygen supply of course being the main limiter of aerobic endurance. This is why as you increase intensity towards VO2max the balance of fat versus glycogen use shifts dramatically in favor of glycogen. So training in a glycogen depleted state (back then we called this bonking) is bad news if you want to increase your aerobic threshold, since the kind of training that has been shown most effective in causing the required adaptations involves repeated maximal efforts. The only training effect you can hope for is nudging your body towards using more fat at lower levels of exertion, thereby saving valuable glycogen. This isn't very relevant for most running events which are typically done at a consistently high VO2max percentage, but beneficial for say cycling races where you have low intensity (riding in the slipstream on the flat) mixed with very high intensity (up a steep grade).