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John Ioannidis Aims His Bazooka at Nutrition Science (2018)

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Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#31

Post by atomical »

atoav wrote: post #11
Upvoter33 wrote: post #2

criticizing nutrition science is ... er ... a low-hanging fruit (sorry)

But exactly these kinds of sciences are part of the reason why a growing part of the population doesn’t trust scientific research and experts anymore. Changing something here for the better has an higher impact on society than doing the same thing e.g. in physics.

The public doesn't trust scientific research because the local news airs studies with controversial claims to outrage and confuse the public.

It's similar to how the YouTube algorithm selects content that will make a person angry.

In both cases the goal is engagement.

Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#32

Post by totalBeginner »

SilasX wrote: post #9
randomsearch wrote: post #4

Earlier quoted context omitted.

“The World Cancer Research Fund report Food, Nutrition, Physical Activity and the Prevention of Cancer provided advice on red and processed meat in 2007. The organisation said the evidence that red and processed meats are causes of bowel cancer is convincing. It advises that people eat no more than 500g of red meat a week (around 70g a day) and avoid processed meats.” https://www.nhs.uk/live-well/eat-well/red-meat-an…

So how much did they weight the utility of eating red meat in order to conclude that severely restricting it would be worth the .074% decrease in death risk? Because that doesn't seem like a significant risk. https://www.cancerresearchuk.org/health-professional/cancer-...

Genuinely curious, where did you see the "0.074% decrease in death risk?"

From the page you linked to: "13% of bowel cancer cases in the UK are caused by eating processed meat.

Bowel cancer risk is 17-30% higher per 100-120g/day of red meat intake, meta-analyses have shown.

Bowel cancer risk is 9-50% higher per 25-50g/day of processed meat intake, meta-analyses have shown; however bowel cancer risk was not associated with processed meat intake in a pooled analysis of UK case-control studies. Colon cancer risk is 12% higher per 1mg/day of haem iron intake, a meta-analysis showed; though bowel cancer risk was not associated with dietary iron intake in a pooled analysis of UK cohort studies.

Serrated bowel polyp risk is 23% higher in people with the highest versus lowest levels of red meat intake, a meta-analysis showed."

https://www.cancerresearchuk.org/health-professional/cancer-...

Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#33

Post by zaphod4prez »

totalBeginner wrote: post #32
SilasX wrote: post #9

Earlier quoted context omitted.

So how much did they weight the utility of eating red meat in order to conclude that severely restricting it would be worth the .074% decrease in death risk? Because that doesn't seem like a significant risk. https://www.cancerresearchuk.org/health-professional/cancer-...

Genuinely curious, where did you see the "0.074% decrease in death risk?" From the page you linked to: "13% of bowel cancer cases in the UK are caused by eating processed meat. Bowel cancer risk is 17-30% higher per 100-120g/day of red meat intake, meta-analyses have shown. Bowel cancer risk is 9-50% higher per 25-50g/day of processed meat intake, meta-analyses have shown; however bowel cancer risk was not associated…

Ok let's run this scenario (please check my math here, I'm not positive I'm doing the probability right). Let's assume we're talking about a man, bc men are more likely to be affected. Your lifetime risk of developing bowel cancer is 7% for males [1]. Bowel cancer risk is 17-30% higher if you eat a quarter pound of red meat per day [2]. But let's go ahead and assume someone does eat that much meat and use 30%. If you get bowel cancer, you have a 25% chance of dying [3]. That means...

lifetime_risk_no_meat = 0.07

lifetime_risk_yes_meat = 0.07 + (0.07*.3)

risk_of_death_given_cancer = 0.25

(lifetime_risk_yes_meat - lifetime_risk_no_meat) /risk_of_death_given_cancer ==> 0.084

So an 0.084% increase in risk of death if we use the most risky scenario available.

[1]: Lifetime risk of bowel cancer https://www.cancerresearchuk.org/health-professional/cancer-...

[2]: https://www.cancerresearchuk.org/health-professional/cancer-...

[3]: Persons-> Crude rate -> UK https://www.cancerresearchuk.org/health-professional/cancer-...

Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#34

Post by ryanwaggoner »

kansface wrote: post #21
api wrote: post #18

Earlier quoted context omitted.

Is there a shortcut? I'm sure some improvements can be made but I am skeptical of the idea that science is just doing it wrong.

> Is there a shortcut? A much, much deeper understanding of how humans work.

Facepalm! How could we have forgotten to pick that up before heading down this road of frustratingly hit-or-miss basic research?!

Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#35

Post by gbear605 »

kansface wrote: post #21
api wrote: post #18

Earlier quoted context omitted.

Is there a shortcut? I'm sure some improvements can be made but I am skeptical of the idea that science is just doing it wrong.

> Is there a shortcut? A much, much deeper understanding of how humans work.

And how do we acquire that?

Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#36

Post by jdminhbg »

dsr_ wrote: post #27
User23 wrote: post #25

Earlier quoted context omitted.

It's almost as if different human populations separated by insurmountable geographic barriers in wildly differing ecological circumstances for myriad millennia underwent selection pressure!

And have mixed-and-matched enough that claiming any sort of "purity" is idiotic. We're all braided together.

I don't think anyone is claiming "purity" at all. Purity, if anything, would make things simpler.

Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#37

Post by gbear605 »

zaphod4prez wrote: post #33
totalBeginner wrote: post #32

Earlier quoted context omitted.

Genuinely curious, where did you see the "0.074% decrease in death risk?" From the page you linked to: "13% of bowel cancer cases in the UK are caused by eating processed meat. Bowel cancer risk is 17-30% higher per 100-120g/day of red meat intake, meta-analyses have shown. Bowel cancer risk is 9-50% higher per 25-50g/day of processed meat intake, meta-analyses have shown; however bowel cancer risk was not associated…

Ok let's run this scenario (please check my math here, I'm not positive I'm doing the probability right). Let's assume we're talking about a man, bc men are more likely to be affected. Your lifetime risk of developing bowel cancer is 7% for males [1]. Bowel cancer risk is 17-30% higher if you eat a quarter pound of red meat per day [2]. But let's go ahead and assume someone does eat that much meat and use 30%. If you…

I believe that your math is wrong because some of your numbers are percents and some are not, and because you divided instead of multiplying. If you are interested in the chance of death, you take the chance of cancer and multiply it by the chance of death given cancer.

lifetime_risk_no_meat = 7% lifetime_risk_yes_meat = 7% + (7%30%) = 9.1% risk_of_death_given_cancer = 25% (lifetime_risk_yes_meat - lifetime_risk_no_meat) risk_of_death_given_cancer = 2.1%*25% = 0.00525 = 0.525%

So by this math, eating a quarter pound of red meat a day causes men in this worse case scenario to die 0.525% more often, which is a sixteen times higher rate than your calculated value.

Of course, that’s not how to actually do the relevant calculations, since (assuming no significant technology changes), everyone will eventually die. Thus you instead need to do calculations based on life expectancy, or better yet on QALY (quality adjusted life years), which adjusts for the quality of life that people live in addition to their age.

Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#38

Post by toasterlovin »

sykhotic wrote: post #15
DenisM wrote: post #10

Earlier quoted context omitted.

From your link: >This is because there is probably a link between eating a lot of red and processed meat, and bowel (colorectal) cancer. Probably? Link? "Link" as in "co-occurring but not necessarily causally related"? No references to the studies or methods? This is the same quality material that has been used to promote eating less fat for several decades, while obesity exploded to record levels.

This is the same quality material that has been used to promote eating less fat for several decades, while obesity exploded to record levels. It’s a bit ironic you are questioning the study with regards to causality and then mention obesity exploding to record levels with an unsubstantiated, implied connection to the promotion of eating less fat. Your coment would have been perfect without the obesity comment since y…

The person you're responding to is not saying that avoiding fat led to obesity. They're simply saying that the obesity epidemic is evidence against the hypothesis that consuming fats leads to becoming fat. Disconfirming a hypothesis is not the same thing as as proving a competing hypothesis.

Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#39

Post by toasterlovin »

oh_sigh wrote: post #22
beagle3 wrote: post #13

Earlier quoted context omitted.

It never was. There were afaik no studies ; basically the advice was given on the chain “dietary cholesterol -> serum cholesterol -> blocked arteries -> cardiac problems” of which the last was convincing, the middle mostly convincing at the time, though much less so now - and the first was just assumed but is now known to be essentially wrong.

So why didn't scientists come out in droves and push back on the anti-egg movement?

Because there's no research grants to be had by going against the prevailing fashionable beliefs in the field.

Re: John Ioannidis Aims His Bazooka at Nutrition Science (2018)

#40

Post by toasterlovin »

jimmy1 wrote: post #14
randomsearch wrote: post #4

Earlier quoted context omitted.

“The World Cancer Research Fund report Food, Nutrition, Physical Activity and the Prevention of Cancer provided advice on red and processed meat in 2007. The organisation said the evidence that red and processed meats are causes of bowel cancer is convincing. It advises that people eat no more than 500g of red meat a week (around 70g a day) and avoid processed meats.” https://www.nhs.uk/live-well/eat-well/red-meat-an…

Studies of communities that have longitivtiy confirm this. For example, the "Ikaria" study, a university of Athen's study of the island of Ikaria, where males reach the age of 90 2.5 times more frequently than Americans, their diet consisted of hardly any red meat at all (and also hardly any sugar), but rather beans, legumes, wild local greens with lemon juice and olive oil, fish, honey, and red wine.

The study you cite did not confirm the red meat hypothesis. It merely failed to disconfirm it. Those are two very different things, which nutrition researches and the general public seem to be incapable of wrapping their heads around.
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