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Red meat and processed food 'not back on the menu' according to new review (nhs.uk)
32 points by open-source-ux on Feb 5, 2020 | hide | past | favorite | 55 comments



I swear if it weren't for the many institutional problems plaguing academia including publish or perish in particular, shoddy bullshit studies like this would never see the light of day.

Even bending over backwards they were barely able to show a tiny correlation from surveys. Meat consumption was the evolutionary step that enabled primates to develop and maintain biologically expensive brains that made them human. There unquestionably had to have been a strong evolutionary pressure to adapt completely to meat eating.

This is just data dredging in pursuit of justification for some kind of weird anti-meat sentiment which has been growing for decades, when the real culprit is already known - it's the sugars that have most likely been killing all of us, although to be honest if the same "gold standard" methods were applied to sugar related studies I'd question those as well. The way the media continues to sensationalize these correlative, broken studies is shameful.


Perhaps there could be a strong evolutionary pressure to adapt to meat eating AND it could cause a slight increase in certain illnesses if consumed regularly by certain populations? If we look at blue zones where people live the longest, one commonality is 95% of their diets are vegetables, grains, and legumes, with limited meat consumption. At the end of the day it comes down to goals and priorities. If performance is a priority, I think meat consumption can be a good thing. If longevity is a priority, limiting meat consumption is probably a good thing. We have to take a nuanced approach. Nutrition science is difficult, and different populations naturally respond in different ways to a variety of diets. Some will naturally thrive on meat heavy diets while others will not.


>If longevity is a priority, limiting meat consumption is probably a good thing

But 90% of people don't seem to understand that literally all studies on meat are of this quality and there's zero reliable evidence that red meat is actually harmful.

However there is reason for bias considering meat gets a bad rap for being environmentally unfriendly and cruel, although both of those things can be solved with modern technology. But neither are valid reasons to dig for dirt with an agenda. That's bad science and studies like these are potentially the results. Not to accuse the authors specifically, but the bias is very likely influencing the direction of research in the field.


re: blue zones.

They also don't smoke, drink, and do regularly exercise. And these things are usually prescribed by their religion.

As soon as you start accounting for confounding variables, correlations between eating meat and bad health outcomes drop significantly. And you're left unable to determine whether it's observing the Sabbath on Saturday or not eating meat that makes them live longer.


Not just certain populations, but each individual is likely to have different nutritional needs for different desired outcomes. Hard to study that though.


This is great. A calm, accessible analysis of a complex, emotive and apparently volatile topic. Well done NHS.

Of interest here's a Freedom of Information request about the consultants Bazian who produced this for the NHS: https://www.whatdotheyknow.com/request/bazian_services_to_th...


I used to read this blog, until I realised every article was:

"This study is limited and warrants further research. This alone does not warrant a change to dietary advice. We encourage people eat per the Eat Well plate, as we've done for 15+ years."

At which point I stopped reading newspaper articles on diet, nor their critiques, and spent that time on following their advice.


No sensible health authority would change dietary advice based on a single study. Consider research like this as discrete steps in one direction or another, with a much longer continuous waveform representing national and population-led understanding.


>red meat: 0.17% over 10 years, 0.41% over 20 years and 0.62% over 30 years

Isn't this essentially nothing? Am I misinterpreting these results?


Welcome to the world of nutrition science, where the methodology is shoddy, the evidence is poor, and the recommendations are ridiculous.


> ... completed a food questionnaire and then were followed up for around 20 years

FFQ are useless. I barely remember what I ate 2 days ago.


> Isn't this essentially nothing?

Essentially nothing: for an individual? Yes. For a population? No.

You or I may not care about a 0.62% increased CVD rate for ourselves over 30 years, but that does translate to 6,200 extra possibly-preventable cases of CVD per million people. That's about 76,000 diagnoses annually in the US alone.


This way of interpreting the data is misleading. For population, it still could mean nothing. People are not living in an isolated environment just eating red meat or processed food and do nothing else. At the population level there are way more factors need to be considered. You can't even imagine how many things in the society will be impacted if people stop eating red meat or the processed food. CVD will be the least of concern at the population level.

So, yes, this tiny effect size means nothing.

Moreover, this tiny effect size could be much smaller than noises in the data.


It could mean nothing, or it could not. But a small effect size alone doesn’t tell you this, and you are correct that there are many factors — that is exactly the point of this study, to tease apart which other factors are causative.

Of course, this study says nothing about what happens if you try to change behavior, that seems like an entirely unrelated point.

Taken together, I’m not sure how you can be so confident that a small effect size therefore means nothing.


How strong is this effect relative to other effects though? With small effects, you get an increased risk of error in the analysis as there could be confounding variables not fully accounted for, reporting errors, etc.

How would this compare, for example, to not smoking, drinking less alcohol, wearing sunscreen, safe sex, not exercising enough, etc.

(Picked things that I think we have a high standard of evidence for and fairly large effect, but that people often neglect due to wanting to do the harmful activity, as with red meat)

For years low salt recommendations were justified based on lessened harm "on a population level" even if individual gains were small. Now it seems that these recommendations were wrong, according to Cochrane reviews.


Smoking increases lung cancer risk 15x-30x, comes at a steep tax-inflated price and people still won't give it up.

I basically read this as "it's ok to eat meat/sausages/whatever".


This is assuming this 0.62% actually shows a TRUE effect.

If it is noise/invalid/a mistake, it means nothing; the actual effect might actually be a DECREASE of CVD as far as we know.

And it is important to also look at all cause mortality; such studies have often shown a decrease in CVD but the same final number of deaths...


You should really include that this was under the assumption of only 2 servings a week, where a serving is about 3.5 ounces. I wonder how the rates change when you assume 2 servings per meal, which seems more in line with peoples actual diets.


7 ounces of steak per meal is average? That's an expensive diet.


Just as bad to lump both red meat and processed food into the same category. The additives in the latter have been shown definitively to do harm, whereas there is less evidence about the former.


Did you read the article?

The analysis and results treats then separately:

"processed meat: you would increase your risk by 0.4% over 10 years, 1.02% over 20 years and 1.74% over 30 years red meat: 0.17% over 10 years, 0.41% over 20 years and 0.62% over 30 years"

> The additives in the latter have been shown definitively to do harm, whereas there is less evidence about the former.

The article is evidence of their relative risk, and it does sound consistent with your prior.


I noticed the risk is higher for poultry than for red meat.

So people eating poultry only can reduce their risk by switching from poultry to steak.


This articles refers only to CVD risk, not total morbidity which is influenced by multiple risk factors.


I haven't read the article yet, but going from the headline, I certainly assumed they were claiming the same/similar risk for both red and processed meat.

From the summary you gave, it certainly does seem like a click-baity headline. Personally I would have hoped for better from the NHS (even if I wouldn't have expected it).


I’m sorry, but that’s simply an unwarranted assumption.


Eh? The figures given are clear (and yes, I've read the article by now) - the risk associated with processed meat is much greater than that with red meat.


I believe the following assumption was the one simonh disagreed could be made: "I certainly assumed they were claiming the same/similar risk for both red and processed meat"

I agree. Headlines should be suggestive of content, but cannot contain all the nuances.


The assumption I’m referring to is just the thing you said, in your post, that you assumed.


Ah, sorry, I see what you mean now. It was the part where you said "unwarranted" that confused me, as the thing I said was warranted by the headline, the very thing I said was the basis for the assumption.


The NHS Choices blog's purpose is to critique the news's coverage of health research. It uses excerpts of other newspaper's articles to refer to those articles.


Interesting how the numbers are pumped up for the headline.

The risk is increased by 7% for eating processed meat, not red meat. And the actual numbers are:

    processed meat: you would increase your risk by 0.4% over 10 years, 1.02% over 20 years and 1.74% over 30 years
    red meat: 0.17% over 10 years, 0.41% over 20 years and 0.62% over 30 years
    poultry: 0.20% over 10 years, 0.54% over 20 years and 1.03% over 30 years


I'm mostly surprised poultry is worse than red meat. I realize the supermarket chickens most people eat are a far cry from their ancestors (ridiculously overfed, grain diets, selectively bred to grow faster and fatter), but cattle have many similar issues.


It is mentioned that the results are barely statistically significant for unprocessed meat; it also states that "poultry could mean plain meat or deep-fried" which makes a huge difference.


Could someone explain to me how could researchers come to these conclusions if there are different factors at play that surely impact the results? The article states that:

> Participants consumed a weekly average of 1.5 servings of processed meat, 3 for unprocessed, 2 for poultry and 1.6 servings of fish. People with higher intake were generally more likely to be smokers, drink more alcohol, have a higher body mass index (BMI) and a lower overall diet quality.

If that's the case then how is it possible for a cohort study to properly control for all of these? Isn't 7% increase in risk basically telling nothing then? The other thing is the methodology. The article says that they used "standard food frequency questionnaire" which I think means Food Frequency Questionnaire. This alone seems like it would have great effects on the efficacy of the research making the results even more questionable.


They use statistical methods to eliminate the confounding variables. But given that they do not understand the fallibility of doing that on extremely noisy data, the conclusions are telling us nothing.

They cannot control anything and it's all just questionnaires.

It's fine too look at these things but they seem to get blown out of proportion every single time, even when industry funded studies come out saying eggs or bacon is fine.

And yes, 7% increased risk is practically nothing. That's baseline risk multiplied by 1.07. It's noise all the way.


> They use statistical methods to eliminate the confounding variables.

Some of those anyway. You can only account for confounders that you know about a priori.

And given they used Food Frequency Questionnaires, it's mostly wasted efforts imho.


I would love to see the BMI as another dimension in the study. Given that a portion of meat would have _10-20x_ more calories than an equal amount of vegetables, you need to try hard to get overweight on a mostly vegetarian diet.

Of course, stating that red meat causes CVD is much more sensationalist than merely confirming that extra weight does it, since it implies that ~90% of the population [0] are making an unhealthy choice.

[0] https://en.wikipedia.org/wiki/Vegetarianism_by_country


However if the vegetarian diet consists of mostly starches and grains it is pretty easy to put on weight.


That's exactly I would love to see BMI as another dimension in the study, as it would fully eliminate this speculation.


Meat is rarely the source of excess calories in a person’s diet.

Sugars, starches, dairy.


The thing about processed food is that it came about in the 50s, at a time when many Americans still remembered the dust bowl. Processed food could be shipped long distances and stored for long times without spoiling and was available at any time of year. It was, among other things, a hedge against starvation.

It's not high quality food, and you should, by all means, prefer fresh food when it is available and you can afford it. But the jihad against processed food may have unpleasant consequences the next time famine conditions arise.


Define “processed food” - I understand it often includes decidedly un-modern steps, such as salting and curing; even doing your own pickling.


https://www.nhs.uk/live-well/eat-well/what-are-processed-foo...

According to the NHS who also did this study, this is the definition of 'processed food'...

I think it's dangerous to use the term processed when it's clearly just the fat, sugars, or other added chemicals and usually not the process that is unhealthy. 'Freezing and baking' is not unhealthy and yet they are what the NHS considers 'processed'.


I'm looking forward to the keto rebuttal.


The standard objections apply:

- Correlation, not causation

- Self-reporting questionaire

- Not controlling for meat quality/sourcing (though at least they differentiate "processed meats")


What rebuttal?

> red meat: 0.17% over 10 years, 0.41% over 20 years and 0.62% over 30 years

0.62% increase over 30 years is next to nothing, especially when you consider that many people have shit diet habits anyway.


I'd actually expect that to be higher than it is, just given that red meat has been vilified for 50+ years by public health officials.

I'm not sure if there's a name for the reverse of healthy user bias, but I like to think of it as blaming baseball for oral cancer, rather than the chewing tobacco common among players in the sport.


Those numbers are assuming 2 servings per week. How many meat eater limits themselves to that few of servings?


The numbers in the study are something like 2 servings meat, 3 chicken, 1.6 fish weekly.


Haven't looked at the original study, but from the article

>>>In terms of the actual difference eating 2 servings a week would make to an individual's baseline risk of CVD, the researchers calculated:

processed meat: you would increase your risk by 0.4% over 10 years, 1.02% over 20 years and 1.74% over 30 years

red meat: 0.17% over 10 years, 0.41% over 20 years and 0.62% over 30 years

poultry: 0.20% over 10 years, 0.54% over 20 years and 1.03% over 30 years


The way your body processes food during ketosis is so different from processing "traditional" diets that I hardly think it would be relevant enough to warrant a rebuttal.

I do like hearing Mark's opinions on such things though: https://www.marksdailyapple.com/what-does-the-who-report-mea...


Note that this wasn't actually a study, they just looked at 6 other studies and based a consensus on that.


That is what we call a meta analysis. It is probably the best thing to look at if you are going to derive conclusions from science.


That alone doesn't make it "not a study"; it's a study of other studies, not a study with new data.


Definitive conclusions shouldn't be derived from observational studies only. Also, the methodology used is very questionable.

We should be more critical about matters concerning our diet, as studies like the former will be used by the media and professionals to back potentially life-changing advices.




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