10 ms·

Can you lose fat if you still have calories available in glycogen storage? Or do you need to first burn through the glycogen? Will only carbs work to replenish

by jmpman 3y ago

Can you lose fat if you still have calories available in glycogen storage? Or do you need to first burn through the glycogen? Will only carbs work to replenish glycogen storage, or will also fat and protein?

v7engine 3y ago
"Your body burns a mixture of fat and glycogen where the glycogen decreases over time. But it does appear to deplete pretty quickly." This is mentioned in the article.
tim-fan 3y ago
I believe in some conditions fat and/or protein can be used to restore glycogen via Gluconeogenesis https://en.wikipedia.org/wiki/Gluconeogenesis https://en.wikipedia.org/wiki/Gluconeogenesis I remember reading that for keto diets it's important to not eat too much protein, otherwise the excess protein may be converted to glucose, replenishing glycogen and knocking you out of ketosis.
- Blackthorn 3y ago
  Gluconeogenesis can't really turn fat into glucose, humans lack a key enzyme for that.
  - arcticbull 3y ago
    This is not accurate. If that were true people who fasted would die after about 3 days, but of course, the longest fast lasted about 350 days. The reality is after 3 days of fasting, your blood glucose level stabilizes. Your body must perform gluconeogenesis to survive because a few types of tissue require glucose to live - those without mitochondria. This means red blood cells and about 30% of the energy requirements of your brain. Pathway is here if you're curious. [1] [1] https://en.wikipedia.org/wiki/Gluconeogenesis https://en.wikipedia.org/wiki/Gluconeogenesis
    - Blackthorn 3y ago
      There's the glycerol part of the fat, sure. But your body can make glucose from a lot more stuff. Namely, proteins.
      - arcticbull 3y ago
        I think when people say "fat" they mean triglycerides - not free fatty acids - which includes the glycerol backbone. So it's not right to say that humans can't turn fat into sugar, they can. Per the wikipedia article 90% of gluconeogenesis happens from lactate, glycerol, alanine and glutamate.
        Blackthorn 3y ago
        Yeah, fair enough. That'll maybe teach me to not type abbreviated nonsense on my phone.
        deleted 3y ago
        [deleted]
        Aerroon 3y ago
        >Per the wikipedia article 90% of gluconeogenesis happens from lactate, glycerol, alanine and glutamate. That's interesting! Glutamine vs glutamate ratio is supposedly something that affects motivation.[0] I wonder if (enough) gluconeogenesis thus boosts motivation? [0] https://www.nature.com/articles/s41386-020-0760-6 https://www.nature.com/articles/s41386-020-0760-6
        wuiheerfoj 3y ago
        Is there an obvious way to modify that ratio?
        Aerroon 3y ago
        The "word on the street" is that oral glutamine supplementation works for this purpose. My personal experience agrees with this (but the effect probably isn't very large). In the morning I mix a tablespoon of glutamine into a glass of water and drink it. You can buy glutamine in supermarkets next to all the other protein supplements (glutamine is the most abundant amino acid in the body). It's also helpful to your immune system. --- That being said, that's 'hearsay'. I am not aware of any studies that show that oral supplementation of glutamine improves motivation. That might just be due to time though. The original study showing that glutamine-to-glutamate ratio in the nuclear accumbens affects motivation was published in 2020.[0] We do know that glutamine does pass the blood brain barrier.[1] There's probably a decent chance that oral supplementation of glutamine works. Some downsides: it can make seizures worse. There's some worry about it having some effect on cancer, although that seems to be mixed - some seem to think it would increase the risk of cancer, others say it decreases it (cancer cells use glutamine as fuel). [0] https://www.nature.com/articles/s41386-020-0760-6 https://www.nature.com/articles/s41386-020-0760-6 [1] https://pubmed.ncbi.nlm.nih.gov/12933350/ https://pubmed.ncbi.nlm.nih.gov/12933350/
- dawnerd 3y ago
  From personal experience you’d have to eat a LOT of protein to kick you out. I do a pretty high protein keto diet and it works great. What really gets people is all the keto blogs talk about eating lots of fat. That great if you are doing keto for a lifestyle choice but if you’re doing it for weight loss you already have the fat and don’t need to boost your intake. Eating a fraction of the suggested macros still maintains satiety.
- deleted 3y ago
  [deleted]
bzjlvewivezw 3y ago
Yes, I think so. This is most likely to happen with a high-fat diet and large amounts of low-mid intensity endurance exercise.
- arcticbull 3y ago
  Studies show that exercise doesn't help you lose any appreciable amount of weight. It's good for you and you should do it, but it doesn't help with weight loss. Only what you eat does. At a high level, it's mostly because (a) exercise just isn't inefficient enough to lose a ton of weight unless you do insane amounts of it. To lose 10lbs through exercise you need to run from SF to LA. (b) humans are notorious compensatory eaters. If you work out, you'll be hungry, and you'll rationalize or sneak extra food, and one muffin un-does like 5 miles of running. [1] agrees, showing that moderate-intensity aerobic exercise done 5x weekly for 30m per day yields no measurable weight loss. [2] shows that adding exercise to diet yields no measurable difference between the diet and the diet+exercise group after 6 months, and after 12 months the difference was two pounds in favor of the exercise group. After a year. [1] https://www.sciencedirect.com/science/article/abs/pii/S0033062018301440 https://www.sciencedirect.com/science/article/abs/pii/S00330... [2] https://onlinelibrary.wiley.com/doi/full/10.1111/j.1467-789X.2008.00547.x https://onlinelibrary.wiley.com/doi/full/10.1111/j.1467-789X...
  - PlunderBunny 3y ago
    Yes - nothing is more likely to make me start a spiel than hearing "eat less, move more".
    - arcticbull 3y ago
      It's interesting how persistent the 'just diet and exercise' thing is when any amount of research will show you that it just doesn't do shit. Your metabolism slows down to compensate for dieting, you eat more to compensate for exercise, etc. The studies that do show any benefit stop after 1 year, and don't really do follow-ups. By 'significant' benefit they mean statistically significant, as the weight loss numbers are really marginal. Then, if you look at 2-year follow-ups for weight-loss studies, they're fucking bleak. 9 in 10 fail and regain the bulk of the weight lost. Imagine a doctor regularly prescribing you pain medication that worked for 1 in 10 people - because that's basically the state of front-line weight management healthcare. The one that really put it into perspective for me was the one that revisited the Biggest Loser participants after 6 years and the mean regain was 70% of their lost weight (90 of the 127lbs average), and they were left with a 20% slower metabolism. [1] [1] https://pubmed.ncbi.nlm.nih.gov/27136388/ https://pubmed.ncbi.nlm.nih.gov/27136388/

by jmpman 3y ago

v7engine 3y ago

"Your body burns a mixture of fat and glycogen where the glycogen decreases over time. But it does appear to deplete pretty quickly." This is mentioned in the article.

tim-fan 3y ago

I believe in some conditions fat and/or protein can be used to restore glycogen via Gluconeogenesis https://en.wikipedia.org/wiki/Gluconeogenesis https://en.wikipedia.org/wiki/Gluconeogenesis I remember reading that for keto diets it's important to not eat too much protein, otherwise the excess protein may be converted to glucose, replenishing glycogen and knocking you out of ketosis.

Blackthorn 3y ago
Gluconeogenesis can't really turn fat into glucose, humans lack a key enzyme for that.
- arcticbull 3y ago
  This is not accurate. If that were true people who fasted would die after about 3 days, but of course, the longest fast lasted about 350 days. The reality is after 3 days of fasting, your blood glucose level stabilizes. Your body must perform gluconeogenesis to survive because a few types of tissue require glucose to live - those without mitochondria. This means red blood cells and about 30% of the energy requirements of your brain. Pathway is here if you're curious. [1] [1] https://en.wikipedia.org/wiki/Gluconeogenesis https://en.wikipedia.org/wiki/Gluconeogenesis
  - Blackthorn 3y ago
    There's the glycerol part of the fat, sure. But your body can make glucose from a lot more stuff. Namely, proteins.
    - arcticbull 3y ago
      I think when people say "fat" they mean triglycerides - not free fatty acids - which includes the glycerol backbone. So it's not right to say that humans can't turn fat into sugar, they can. Per the wikipedia article 90% of gluconeogenesis happens from lactate, glycerol, alanine and glutamate.
      - Blackthorn 3y ago
        Yeah, fair enough. That'll maybe teach me to not type abbreviated nonsense on my phone.
        deleted 3y ago
        [deleted]
      - Aerroon 3y ago
        >Per the wikipedia article 90% of gluconeogenesis happens from lactate, glycerol, alanine and glutamate. That's interesting! Glutamine vs glutamate ratio is supposedly something that affects motivation.[0] I wonder if (enough) gluconeogenesis thus boosts motivation? [0] https://www.nature.com/articles/s41386-020-0760-6 https://www.nature.com/articles/s41386-020-0760-6
        wuiheerfoj 3y ago
        Is there an obvious way to modify that ratio?
        Aerroon 3y ago
        The "word on the street" is that oral glutamine supplementation works for this purpose. My personal experience agrees with this (but the effect probably isn't very large). In the morning I mix a tablespoon of glutamine into a glass of water and drink it. You can buy glutamine in supermarkets next to all the other protein supplements (glutamine is the most abundant amino acid in the body). It's also helpful to your immune system. --- That being said, that's 'hearsay'. I am not aware of any studies that show that oral supplementation of glutamine improves motivation. That might just be due to time though. The original study showing that glutamine-to-glutamate ratio in the nuclear accumbens affects motivation was published in 2020.[0] We do know that glutamine does pass the blood brain barrier.[1] There's probably a decent chance that oral supplementation of glutamine works. Some downsides: it can make seizures worse. There's some worry about it having some effect on cancer, although that seems to be mixed - some seem to think it would increase the risk of cancer, others say it decreases it (cancer cells use glutamine as fuel). [0] https://www.nature.com/articles/s41386-020-0760-6 https://www.nature.com/articles/s41386-020-0760-6 [1] https://pubmed.ncbi.nlm.nih.gov/12933350/ https://pubmed.ncbi.nlm.nih.gov/12933350/
dawnerd 3y ago
From personal experience you’d have to eat a LOT of protein to kick you out. I do a pretty high protein keto diet and it works great. What really gets people is all the keto blogs talk about eating lots of fat. That great if you are doing keto for a lifestyle choice but if you’re doing it for weight loss you already have the fat and don’t need to boost your intake. Eating a fraction of the suggested macros still maintains satiety.
deleted 3y ago
[deleted]

bzjlvewivezw 3y ago

Yes, I think so. This is most likely to happen with a high-fat diet and large amounts of low-mid intensity endurance exercise.

arcticbull 3y ago
Studies show that exercise doesn't help you lose any appreciable amount of weight. It's good for you and you should do it, but it doesn't help with weight loss. Only what you eat does. At a high level, it's mostly because (a) exercise just isn't inefficient enough to lose a ton of weight unless you do insane amounts of it. To lose 10lbs through exercise you need to run from SF to LA. (b) humans are notorious compensatory eaters. If you work out, you'll be hungry, and you'll rationalize or sneak extra food, and one muffin un-does like 5 miles of running. [1] agrees, showing that moderate-intensity aerobic exercise done 5x weekly for 30m per day yields no measurable weight loss. [2] shows that adding exercise to diet yields no measurable difference between the diet and the diet+exercise group after 6 months, and after 12 months the difference was two pounds in favor of the exercise group. After a year. [1] https://www.sciencedirect.com/science/article/abs/pii/S0033062018301440 https://www.sciencedirect.com/science/article/abs/pii/S00330... [2] https://onlinelibrary.wiley.com/doi/full/10.1111/j.1467-789X.2008.00547.x https://onlinelibrary.wiley.com/doi/full/10.1111/j.1467-789X...
- PlunderBunny 3y ago
  Yes - nothing is more likely to make me start a spiel than hearing "eat less, move more".
  - arcticbull 3y ago
    It's interesting how persistent the 'just diet and exercise' thing is when any amount of research will show you that it just doesn't do shit. Your metabolism slows down to compensate for dieting, you eat more to compensate for exercise, etc. The studies that do show any benefit stop after 1 year, and don't really do follow-ups. By 'significant' benefit they mean statistically significant, as the weight loss numbers are really marginal. Then, if you look at 2-year follow-ups for weight-loss studies, they're fucking bleak. 9 in 10 fail and regain the bulk of the weight lost. Imagine a doctor regularly prescribing you pain medication that worked for 1 in 10 people - because that's basically the state of front-line weight management healthcare. The one that really put it into perspective for me was the one that revisited the Biggest Loser participants after 6 years and the mean regain was 70% of their lost weight (90 of the 127lbs average), and they were left with a 20% slower metabolism. [1] [1] https://pubmed.ncbi.nlm.nih.gov/27136388/ https://pubmed.ncbi.nlm.nih.gov/27136388/