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According to Dr. Robert Lustig of University of California fructose is indeed worse than sugar. [1] It's been a good while since I've watched this video. As fa

by ephbit 4y ago

According to Dr. Robert Lustig of University of California fructose is indeed worse than sugar. [1] It's been a good while since I've watched this video. As far as I remember, he argues that fructose is to the human body strikingly similar to alcohol. Since (unlike glucose) fructose can neither be utilized by muscles nor by the brain, it gets treated more or less like a toxic substance in the liver. In the video Lustig claims that fructose might even be harder on the liver than alcohol. So I'd conclude: more fructose --> less healthy. Thus High Fructose Corn Sirup HFCS = far from healthy. [1] https://www.uctv.tv/shows/Fat-Chance-Fructose-2-0-25641 https://www.uctv.tv/shows/Fat-Chance-Fructose-2-0-25641

_yb2s 4y ago
High fructose corn syrup and sucrose (table sugar, which is a combination of fructose and glucose) have roughly the same amount of fructose- 50%. Also, what Lustig says is nonsense and isn't backed by any plausible mechanism or observational evidence. Alcohol and fructose aren't metabolized very similarly at all. He points out that if liver glycogen is constantly full, the liver has to convert extra fructose to fat (de novo lipogenesis) [1], eventually leading to fatty liver disease, which also happens to alcohol, and short chain fats (e.g. from eating fiber that gets fermented in the gut). As he admits in his own paper this doesn't happen unless you are massively overeating. People that are eating in calorie balance will use the fructose immediately for cellular energy as designed, with no ill effects. Reglarly overeating without exercising much isn't great for your liver because it keeps glycogen overfilled... but it really doesn't matter much what you're overeating. [1] https://academic.oup.com/advances/article/4/2/226/4591631?login=true https://academic.oup.com/advances/article/4/2/226/4591631?lo...
- ephbit 4y ago
  Agreed, fructose combined with overeating will lead likely to problems, fructose alone often not. But what do you make of this passage in the abstract of the linked paper? > Thus, fructose can exert detrimental health effects beyond its calories and in ways that mimic those of ethanol, its metabolic cousin. Indeed, the only distinction is that because fructose is not metabolized in the central nervous system, it does not exert the acute neuronal depression experienced by those imbibing ethanol. These metabolic and hedonic analogies argue that fructose should be thought of as “alcohol without the buzz.” As to your knowledge these claims about fructose and ethanol being "metabolic cousins" are false? Do you have any references for this?
  - _yb2s 4y ago
    > As to your knowledge these claims about fructose and ethanol being "metabolic cousins" are false? Do you have any references for this? Ethanol is metabolized ethanol->acetaldehyde->acetate->acetyl CoA whereas fructose is metabolized through the fructolysis pathway, which eventually enters glycolysis the same as other carbohydrates. All energy nutrients eventually end up at acetyl CoA and enter the citric acid cycle, but there is nothing uniquely similar about fructose and alcohol besides being metabolized only in the liver, which is also done for a lot of other nutrients from food. This is all in any basic undergrad biochemistry textbook. Short chain fats from fermented vegetable fiber in the gut for example are widely regarded as super healthy, and are also metabolized in the liver, and nobody says "vegetables are basically just alcohol without the buzz." Lustig is just confused in my opinion, and he has a particular type of personality where conflicting evidence entrenches rather than weakens his confused opinion. I had some initial interest in learning more about his ideas before I actually met him at a conference (I am a PI researcher in this field) and found him to be arrogantly dismissive of any and all technical questions and criticisms, without trying to understand what people are saying.
- rob_c 4y ago
  Please stop defending HFCS. If you've ever lived outside of the US for more than a week you'll realise what an offence to the pallet it is, let alone what it must be doing to your body. Plus didn't we recently realise that fructose genuinely causes the gut to stop digesting good properly?... Overly processed sugar is also bad yes, but govt subsidised HFCS and corn bio-fuel are an affront to common sense.
  - stjohnswarts 4y ago
    We're defending chemistry HFCS and sugar are basically the same thing to the human body and contain very similar amounts of (nutritionally devoid) glucose and sucrose. Anyone who thinks otherwise is living in a fantasy land.

by ephbit 4y ago

_yb2s 4y ago

High fructose corn syrup and sucrose (table sugar, which is a combination of fructose and glucose) have roughly the same amount of fructose- 50%. Also, what Lustig says is nonsense and isn't backed by any plausible mechanism or observational evidence. Alcohol and fructose aren't metabolized very similarly at all. He points out that if liver glycogen is constantly full, the liver has to convert extra fructose to fat (de novo lipogenesis) [1], eventually leading to fatty liver disease, which also happens to alcohol, and short chain fats (e.g. from eating fiber that gets fermented in the gut). As he admits in his own paper this doesn't happen unless you are massively overeating. People that are eating in calorie balance will use the fructose immediately for cellular energy as designed, with no ill effects. Reglarly overeating without exercising much isn't great for your liver because it keeps glycogen overfilled... but it really doesn't matter much what you're overeating. [1] https://academic.oup.com/advances/article/4/2/226/4591631?login=true https://academic.oup.com/advances/article/4/2/226/4591631?lo...

ephbit 4y ago
Agreed, fructose combined with overeating will lead likely to problems, fructose alone often not. But what do you make of this passage in the abstract of the linked paper? > Thus, fructose can exert detrimental health effects beyond its calories and in ways that mimic those of ethanol, its metabolic cousin. Indeed, the only distinction is that because fructose is not metabolized in the central nervous system, it does not exert the acute neuronal depression experienced by those imbibing ethanol. These metabolic and hedonic analogies argue that fructose should be thought of as “alcohol without the buzz.” As to your knowledge these claims about fructose and ethanol being "metabolic cousins" are false? Do you have any references for this?
- _yb2s 4y ago
  > As to your knowledge these claims about fructose and ethanol being "metabolic cousins" are false? Do you have any references for this? Ethanol is metabolized ethanol->acetaldehyde->acetate->acetyl CoA whereas fructose is metabolized through the fructolysis pathway, which eventually enters glycolysis the same as other carbohydrates. All energy nutrients eventually end up at acetyl CoA and enter the citric acid cycle, but there is nothing uniquely similar about fructose and alcohol besides being metabolized only in the liver, which is also done for a lot of other nutrients from food. This is all in any basic undergrad biochemistry textbook. Short chain fats from fermented vegetable fiber in the gut for example are widely regarded as super healthy, and are also metabolized in the liver, and nobody says "vegetables are basically just alcohol without the buzz." Lustig is just confused in my opinion, and he has a particular type of personality where conflicting evidence entrenches rather than weakens his confused opinion. I had some initial interest in learning more about his ideas before I actually met him at a conference (I am a PI researcher in this field) and found him to be arrogantly dismissive of any and all technical questions and criticisms, without trying to understand what people are saying.
rob_c 4y ago
Please stop defending HFCS. If you've ever lived outside of the US for more than a week you'll realise what an offence to the pallet it is, let alone what it must be doing to your body. Plus didn't we recently realise that fructose genuinely causes the gut to stop digesting good properly?... Overly processed sugar is also bad yes, but govt subsidised HFCS and corn bio-fuel are an affront to common sense.
- stjohnswarts 4y ago
  We're defending chemistry HFCS and sugar are basically the same thing to the human body and contain very similar amounts of (nutritionally devoid) glucose and sucrose. Anyone who thinks otherwise is living in a fantasy land.