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Why cancer cells waste so much energy

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Re: Why cancer cells waste so much energy

#191

Post by deeviant »

astrostl wrote: post #187
deeviant wrote: post #186

Earlier quoted context omitted.

They analyzed multiple studies that included 272,216 people, they scored the subjects for LCD (higher score, less carbs). Statistically, the study found an overwhelming (my adjective) correlation that the higher a population scores on the LCD scale, the higher their mortality, showing an average of ~30% higher mortality for those eat a low carb diet. Pretty much every major study that has done this has found similar…

Nod to that. Where I'm going is the possibility of comparing people with "normal" diets and low-carb diets, and thus running the risk of comparing people who do not feel compelled to lose weight for health reasons and those who do. Same story as the various vitamin supplementation paradoxes, which can also be influenced by the fact that people supplementing are more likely to have some pre-existing cause to worry abo…

The studies control for weight and many other health factors. Controlling for weight basically counters your suggestion outright.

There are also many diets that aren't keto so the population of people who felt compelled to lose weight but chose not to do a keto diet, but perhaps a low fat diet (which tends to be high carb) are well represented in the study, once again rebuffing your hypothesis.

In terms of your vitamins supplementation paradoxes, which is a separate point. I also disagree with with you there (these supplement studies also control for various health factors as well), and feel it's much more the problem of absolutely no regulation and there really is nobody making sure the supplement contains the thing it says it is in the quantities it says it does, with nothing else. Also people tend to over do things, and over supplement with the "if some is good more is better". Taking to much vitamin C for instance, spikes your iron absorption, and iron is the most powerful oxidant in your body, or just taking too much iron outright. I could go on and on about supplements, but I'll spare you.

Re: Why cancer cells waste so much energy

#192

Post by deeviant »

astrostl wrote: post #188
deeviant wrote: post #169

Earlier quoted context omitted.

The literal name of the study is "Low-carbohydrate diets and all-cause mortality: a systematic review and meta-analysis of observational studies". It specifically found " Low-carbohydrate diets were associated with a significantly higher risk of all-cause mortality and they were not significantly associated with a risk of CVD mortality and incidence." Perhaps you are on the "oh but the study does specifically say, "l…

> People don't eat a low carb diet by accident, when they do they often follow the horrible advice given by the many misguided keto diet proponents: eat low carb, high fat, medium protein. This is not remotely my anecdotal experience. The overwhelming majority of those I know that I have dabbled with low carb ran the bunless burger, chicken wings, bacon, and steak game and I would guess that their macro intake was hi…

burger, bacon, steak? This is your "medium" fat diet? Ok.

Regardless the studies are quite clear. It doesn't matter the fat/protein ratio, the diets with the lowest carbs produce the highest amount of death.

Re: Why cancer cells waste so much energy

#193

Post by nerdbaggy »

wittyreference wrote: post #184
nerdbaggy wrote: post #168

Earlier quoted context omitted.

This is fanatics thanks! The inflammation from tumor removal causing cancer cells to awaken is very interesting. I had a partial nephrectomy, so hypothetically my chances of reoccurrence is slightly higher since I had my tumor removed? But of course we couldn’t leave it in either. Is the staging have anything to do with how likely they are to wake up?

It's probably not meaningfully higher - this discovery was made a long time ago, and since then we've had a lot of research into which tumors it's really relevant to, and those tumors now get anti-inflammatory medication as a standard part of treatment to prevent just that from happening. The staging is just ("just") a reflection of the primary cancer mass, which is really predictive of outcomes. It's generally not d…

Much appreciated, thanks so much

Re: Why cancer cells waste so much energy

#194

Post by astrostl »

deeviant wrote: post #192
astrostl wrote: post #188

Earlier quoted context omitted.

> People don't eat a low carb diet by accident, when they do they often follow the horrible advice given by the many misguided keto diet proponents: eat low carb, high fat, medium protein. This is not remotely my anecdotal experience. The overwhelming majority of those I know that I have dabbled with low carb ran the bunless burger, chicken wings, bacon, and steak game and I would guess that their macro intake was hi…

burger, bacon, steak? This is your "medium" fat diet? Ok. Regardless the studies are quite clear. It doesn't matter the fat/protein ratio, the diets with the lowest carbs produce the highest amount of death.

This is not my diet, it is the diet I commonly observe from those going simply lo-carb or attempting "keto": hi-protein, rather than hi-fat. This directly questions the unvalidated assertion that, "People don't eat a low carb diet by accident, when they do they often follow the horrible advice given by the many misguided keto diet proponents: eat low carb, high fat, medium protein."

Hi-protein is glucogenic and thus not ketogenic, so the ratio would seem to matter. So would the resolution between an avocado and a fistful of bacon, given the safe assumption that the materials and cooking of them rate to have different impacts on human health.

This is backed by other meta-analyses such as https://www.thelancet.com/journals/lanpub/article/PIIS2468-2... :

> Both high and low percentages of carbohydrate diets were associated with increased mortality, with minimal risk observed at 50–55% carbohydrate intake. Low carbohydrate dietary patterns favouring animal-derived protein and fat sources, from sources such as lamb, beef, pork, and chicken, were associated with higher mortality, whereas those that favoured plant-derived protein and fat intake, from sources such as vegetables, nuts, peanut butter, and whole-grain breads, were associated with lower mortality, suggesting that the source of food notably modifies the association between carbohydrate intake and mortality.

Stressing that both hi carb (contra your claim) and lo carb when specifically overindexed on animal protein had higher mortality, not just lo carb.

Re: Why cancer cells waste so much energy

#195

Post by astrostl »

deeviant wrote: post #191
astrostl wrote: post #187

Earlier quoted context omitted.

Nod to that. Where I'm going is the possibility of comparing people with "normal" diets and low-carb diets, and thus running the risk of comparing people who do not feel compelled to lose weight for health reasons and those who do. Same story as the various vitamin supplementation paradoxes, which can also be influenced by the fact that people supplementing are more likely to have some pre-existing cause to worry abo…

The studies control for weight and many other health factors. Controlling for weight basically counters your suggestion outright. There are also many diets that aren't keto so the population of people who felt compelled to lose weight but chose not to do a keto diet, but perhaps a low fat diet (which tends to be high carb) are well represented in the study, once again rebuffing your hypothesis. In terms of your vitam…

"Weight" is a poor control. BMI is a better one. Going back over the study, it looks like the controls are listed in table 2. 12/17 appear to adjust for BMI, with the following note from the authors regarding the resolution: "We were unable to perform a subgroup analysis according to the body-mass index because the mean values were not stated or estimable in the majority of the reports." (emphasis mine) This certainly doesn't throw out the results for me, but I still find myself asking the same question. But moreso the protein vs fat ratio question, as in my reply to the subthread above. With only three macronutrients in play, I can't fathom throwing two of them together.

Re: Why cancer cells waste so much energy

#196

Post by deeviant »

astrostl wrote: post #195
deeviant wrote: post #191

Earlier quoted context omitted.

The studies control for weight and many other health factors. Controlling for weight basically counters your suggestion outright. There are also many diets that aren't keto so the population of people who felt compelled to lose weight but chose not to do a keto diet, but perhaps a low fat diet (which tends to be high carb) are well represented in the study, once again rebuffing your hypothesis. In terms of your vitam…

"Weight" is a poor control. BMI is a better one. Going back over the study, it looks like the controls are listed in table 2. 12/17 appear to adjust for BMI, with the following note from the authors regarding the resolution: "We were unable to perform a subgroup analysis according to the body-mass index because the mean values were not stated or estimable in the majority of the reports ." (emphasis mine) This certain…

You are reading way too far into my words when I'm speaking causally, I do not write my comments in the dense and precise language in which studies are written as it's a bit overwrought for casual discourse. I had hoped you would give me the benefit of the doubt that when I said weight you would take that to mean some sort of levelized metric.

The people that do these studies aren't as dumb as you seem to think they are nor are the type of confounding variables you are expressing foreign to them. Not even study can get exactly the quality or quantity of date it wants, that's why its a good idea to look at multiple studies and examine large-scale trends and repeatably, which is the type of studies I linked.

Re: Why cancer cells waste so much energy

#197

Post by excannuck »

wittyreference wrote: post #104
excannuck wrote: post #53

Earlier quoted context omitted.

Since you were a cancer researcher in a previous life, may I ask you a question I thought of commenting on another's comment? If cancer cells have high metabolic requirements, couldn't you attack them by: 1. lowering the caloric intake of the patient 2. Making the glucose the patient intakes mildly radioactive, say with a beta or an alpha emitter [1]. As the patient is strictly kept on a low caloric diet, the radioac…

Great questions. 1. We do attempt to attack cancers by reducing their available energy. That's why, at one point, a major field of research in cancer therapeutics was interfering with angiogenesis, because cancers will secrete messengers that help grow them dedicated (if crappy, low-quality) blood vessels. The issue with "starving" them more starkly is that they're very good at getting a share (e.g., forcing the body…

Thank you for this answer, I'll study it carefully. Sorry I didn't thank you earlier for your answer, but with kids it's very busy.

Re: Why cancer cells waste so much energy

#198

Post by astrostl »

deeviant wrote: post #196
astrostl wrote: post #195

Earlier quoted context omitted.

"Weight" is a poor control. BMI is a better one. Going back over the study, it looks like the controls are listed in table 2. 12/17 appear to adjust for BMI, with the following note from the authors regarding the resolution: "We were unable to perform a subgroup analysis according to the body-mass index because the mean values were not stated or estimable in the majority of the reports ." (emphasis mine) This certain…

You are reading way too far into my words when I'm speaking causally, I do not write my comments in the dense and precise language in which studies are written as it's a bit overwrought for casual discourse. I had hoped you would give me the benefit of the doubt that when I said weight you would take that to mean some sort of levelized metric. The people that do these studies aren't as dumb as you seem to think they…

Some of them did only consider weight. It is the conclusion of the meta itself a mean BMI couldn't be determined from the 12/17 that had it. I don't think those running the studies are at all dumb. They are often focused on specific things, and to the exclusion of generalizable conclusions. I do find it odd that even mean BMI wasn't of apparent interest in diet studies, but I haven't gone thru each sub-study to see why or why not.

I wouldn't feel comfortable reading too much into this one's conclusion. "Low-carb w/o any additional specificity looks like bad news" seems technically fair to me, but actual diets are going to tend to distinguish fat and protein as well as their sources so that isn't a a very logical stopping point for an actual decision. Including core concerns like fat vs protein and plant vs animal sources can yield different conclusions, as the meta linked in the sub-thread above did.

Re: Why cancer cells waste so much energy

#199

Post by hutzlibu »

wittyreference wrote: post #181
hutzlibu wrote: post #162

Earlier quoted context omitted.

", there are about eight major functional changes in the cell needed to go from 'cell' to 'cancer cell'" Can you summarize them, if you haven't done so elsewhere? Anyway thanks. And you should consider writing a book about it ..

(5) Tissue Invasion. Solid cells generally sit on a foundation called basement membrane. Tissue invasion means "fuck basement membrane, I'm cutting through it and getting into the sewer pipes (blood vessels) below!" This actually has two consequences. One is that, well, it's not really cancer until it can escape its original confines - then it's just a pre-cancerous growth. There are a lot of cellular proliferative c…

I bookmarked it, and read it in detail step by step.

Thanks!

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