The Latest Study on Red Meat and Heart Disease: A Red Herring | Hacker News Reader

The Latest Study on Red Meat and Heart Disease: A Red Herring

unsettledscience.substack.com

129 pointsRelaxedTree143 comments

I wonder how many of these studies become self-fulfilling prophecies. Imagine the following scenario. A study claiming red meat is harmful is widely reported in the mainstream media. After reading about this study, health conscious people cut back on red meat while people who don't look after their health continue to eat the same quantity red meat. As a result of these changes, studies conducted years later find a stronger correlation between red meat and unhealthy people.

I’m having trouble locating it at the moment, but an article was shared here a few months ago that suggested something similar happened with health and dietary fat, back when it was still considered harmful. The correlation gradually disappeared after enough studies debunked the causality hypothesis.

Debunked the causality hypothesis meaning that probably saturated fat intake, after going down on average, no longer correlates with coronary disease? Could you ELI5 that? I'm not familiar with the research or the claims.

Debunking the idea that fat intake causes high cholesterol and other health issues. There seemed to be some correlation, but causality was spurious.

The author of this post is not a scientist, but rather a journalist with no scientific credentials, who has a long history of being a promoter and propagandist for the meat industry:

"Meat lobby peddles doubt to undermine dietary guidelines

The Dietary Guidelines for Americans, updated every five years, never fails to cause a stir. For the current revision, released in February, a federally appointed scientific committee — after a two-year review of the latest research and numerous public hearings — has recommended (PDF) lowering consumption of red meat and processed meat.

Despite being fairly tepid, this advice set off a media firestorm, driven by a defensive meat industry and others who have been muddying the waters for some time on the role of meat in the diet. The meat lobby is taking full advantage of the current “debate.”

Adding to the confusion is Nina Teicholz, the best-selling author of “The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet,” whose recent attempts to discredit the committee’s recommendations on meat have been published in The New York Times, alongside meat industry trade publications such as Beef Magazine and Cattle Network."

http://america.aljazeera.com/opinions/2015/5/meat-lobby-pedd...

The field of nutrition is self-undermining given how frequently it's inverted its advice, and the prevalence of pseudo-scientific studies.

As COVID has shown, "scientists" are incredibly powerful in our society to the extent that they can shut down civilization overnight, force billions of people to take experimental substances, repeatedly lie to both population and politicians in order to generate compliance with no consequences, eliminate all criticism of themselves anywhere except individual blogs and all this with no accountability mechanisms whatsoever.

So, good for Nina? We need journalists investigating and undermining pseudo-scientists, just as it's widely recognized that a healthy democracy needs journalists to investigate and undermine corrupt/lying politicians.

We've reached the point where, if "substack" is in the URL and it's not a person who I am already familiar with, I ignore it completely. Maybe these bloggers are right, maybe they're not, but I don't have enough cycles to actually vet them all myself.

Nutrition research is complicated, but the odds of a nutrition blogger on substack unlocking some "secret" that won't eventually make it into more mainstream science publications seems relatively low to me.

Not only is Nina Teicholz a well-established journalist, but she is the author of this book, which made a huge splash and has 2,000+ Amazon Reviews: https://www.amazon.com/Big-Fat-Surprise-Butter-Healthy/dp/14...

Oh, wow -- I love Nina Teicholz! I came across this talk by her a few years ago and it made a massive impression on me: https://www.youtube.com/watch?v=Q2UnOryQiIY&t=29s

I have often wondered:

A - Are meats unhealthy, or, is it the food fed (grains on a foodlot) to the animal that negatively influences the health profile? [1]

B - If meats are so unhealthy, why are the bushmen superfit and incredibly healthy into old age despite having a significant amount of meat ~25% in their diet? [2] & [3]

I recognize that some animals raised on healthy grass-fed diets may have health profiles more similar to healthy fish than conventional grain fed red meat [4] & [5]

[1] https://chriskresser.com/why-grass-fed-trumps-grain-fed-and-...

[2] https://www.youtube.com/watch?v=KWUlrTJoE70

[3] https://www.exploring-africa.com/en/botswana/san-or-bushmen/...

[4] https://www.fda.gov/food/metals-and-your-food/mercury-levels...

[5] https://blog.dana-farber.org/insight/2016/02/are-grass-fed-b...

10% reach 60. No numbers above that. They are healthy while alive, but don’t live longer than people from developed nations.

Look, the discussions around bad health effects of meat consumption all resolve around heart disease and cancer. The numbers are pretty irrelevant for people below 60 or so. We are essentially optimizing lifespan and are wondering what causes diseases in old age, like 70+.

It makes zero sense to look at bushmen or ask the paleo fairy, because most of them die earlier than most people in developed nations.

If we talk about health and well-being, yes, the average bushman alive is probably healthier than the average 60 year old westerner, because the sick people died in the bush but not here and because they move around a lot more. It is literally comparing the fittest 10% against a society that includes also the sick-but-still-alive.

> They are healthy while alive

If that's true, it would imply that they don't die of ill health (disease) but of accidents (eaten by lion) or incredibly curable stuff (e.g. bacterial infection).

So their lifestyle is definitely something to mimick / learn from, as we can easily prevent the healthy person dying causes of death in the first world.

> as we can easily prevent the healthy person dying causes of death in the first world.

Citation needed. Accidental deaths from motor vehicle injuries plus other factors are disturbingly common in the first world.

Doesn't need a citation since other populations do similarly. Unless you insist barbecues are causing mass extinction.

Barbecues causing mass extinction? Now that's one hell of a strawman. Citation still needed that modern society can "easily prevent" fatalities amongst healthy people, because it happens in all developed societies.

Or it implies that people with debilitating conditions don't survive for very long because the Bushman lifestyle is much worse for them in a wide variety of ways, so don't get factored into assessments of the surviving population's general health.

More generally, the fact that a specific group of people who live outdoors and forage and hunt for food are generally in quite good physical shape is probably a better indicator that exercise is good for the physique (and lots of food and a sedentary lifestyle bad for it), than an indication we should go to the supermarket and buy more red meat in proportion to the amount they consume it. Older people can be wiry and surprisingly agile in vegetarian communities where there's [just] enough food and their traditional lifestyle entails walking around everywhere too, but that doesn't mean vegetarianism is a solution to first world dietary problems either. I'd be cautious about conflating agile with free from discomforting ailments too.

No, that would imply they die of illness more quickly and sooner as well as of accidents. It does not have to be incredibly curable, all it needs if for better Healthcare making some difference.

> the paleo fairy, because most of them die earlier than most people in developed nations

I require a source on the average timespan of paleo fairies.

By timespan do you mean the time that they remain in a Paleo diet? Or did you mean lifespan?

...either would be good.

What evidence is there that bushmen have a long healthy life? Please don’t cite a YouTube video or blog as a reference.

Find a bushman that lives a bushman life but has access to modern medicine facilities first, then we can ask that question.

Because this is exactly how bad dietary research is done. Comparing a bushman with a westerner and drawing conclusions that one diet is healthier than another.

> conventional grain fed red meat

"Grain fed" is not conventional.

"grain fed" IS conventional as in "in accordance with general practice; customary", it isn't conventional as in "traditional". Conventional is a poor word choice for this usage.

Buying grass raised beef is difficult or expensive in most of North America.

Expensive perhaps, but not that expensive. Difficult? It’s in every Kroger which is the largest grocer in the USA (afaicr), and it’s also in every Walmart. There’s a lot of beef and a lot of grass fed beef in the USA. If America simply stopped wasting so much food it would likely lower prices enough to make higher quality foods more affordable.

100% grass fed or "grass fed and grass finished" is a bit harder to find I think?

What is grass finished?

Finishing beef is what happens in the feedlot at the end to fatten them up. "grass fed" beef has in the past occasionally meant beef that fed on pasture all its life until it got to the feedlot where they stuffed it full of grain until it was well marbled. Grass finished means they only ate grass in the feedlot too. 100% grass fed has similar implications. You can pretty much tell. If the fat from the meat has a chartreuse tinge instead of off white, if after rendering it has a lower melting point, and if it tastes more like a neutral vegetable oil than a rich and creamy bacon grease, then its probably all grass.

Edit: neutral is perhaps a bit harsh, its subtle and pleasant, it only compliments the meat's flavor, not drives it. Grain fed fat is like an ice cream sunday in comparison. Lots of flavor and so rich. Its like something that has so much sugar in it, it almost makes your mouth burn.

I can't say I've found grain fed to be anything other than a bit bland and greasy. That being said, it's usually been Aberdeen Angus, which is okayish at best.

What kind of grai would they be getting fed? That probably matters too.

100% grass fed is the default, although strictly speaking over winter cows would be fed silage and "hard feed" which might contain grains and legumes.

The world is bigger than North America.

I have no experience buying beef outside of North America so I can’t speak to that.

Regarding your point B, the current US government guidelines that the current article rails against as not being scientific enough actually say:

> The core recommendations of the Guidelines state that a healthy diet for all Americans should include vegetables, fruits, grains (half of which should be whole grains), low or non-fat dairy, and a variety of protein foods, including seafood, lean meats and poultry, eggs, legumes (beans and peas), and nuts, seeds, and soy products. Further, Americans are told to keep saturated fat content below 10% of calories (why the DGA recommends lean meat and low or non-fat dairy), added sugars below 10% of calories, and salt below 2300mg per day.

So they don't seem particularly out of line with the diet of your bushmen:

> The Bushmen are hunter-gatherers, 75% of their diet consists of vegetable, including berries, walnuts, roots and melons, that are mainly harvested by women; while the remaining 25% is made up of meat that is hunted by men who hunt, using poisoned arrows and spears.

(It's not clear how those percentages are measured, volume, weight, calories?)

And the general advice around the world is "eat less red meat, especially processed meat" which seems remarkably tame compared with the anti-meat jihad that some people seem to think is occuring.

e.g. https://www.nhs.uk/live-well/eat-well/food-types/meat-nutrit...

> Meat is a good source of protein, vitamins and minerals in your diet. However, if you currently eat more than 90g (cooked weight) of red or processed meat a day, the Department of Health and Social Care advises that you cut down to 70g.

70g is almost no meat. And not nearly enough.

Low fat/non fat dairy is not healthy, nor is most low fat/non fat replacements because sugar is added to increase flavor.

Sometimes that is true, sometimes not. However, I will say my recent experience has been that I have craved a lot more sugar from external sources (e.g. honey) when cutting out full fat yogurt from my diet even though I tried to supplement my diet with a lot more unsaturated fats to try and avoid this.

Comparing one small homogenous group of people to a very large heterogeneous group of people would require controlling for a rather large set of variables. I don’t see that working well. Additionally, when looking at individuals within a single family we find variances where a diet will work for one and not for another, this applies to workout regimens and the like as well.

I would say more study is needed across the board.

> Are meats unhealthy, or, is it the food fed (grains on a foodlot) to the animal that negatively influences the health profile?

I think there's a difference between healthy food, okay food, and unhealthy food.

Something ultra processed, high in sugar, and low in other macro and micro nutrients is probably unhealthy.

I think "red meat" is unlikely to be very unhealthy - in the same way a Twinky is. But maybe pepperoni sticks aren't too far behind...

I'm not sure why so many people are convinced that red meat - in most of its forms - is one of the best foods you can possibly eat.

There's a mountain of evidence that a lot of vegetables are really good for you. There's not much counter evidence that they're really bad for you. On the flip side, there's not a lot of evidence that red meat is super healthy. And there is a decent amount of evidence that it isn't.

The human body is poor at processing cellulose. You need a lot of plants to equal the nutrients from meat. You can do it, but a cheeseburger, a multivitamin, adequate sun, and good exercise is also a healthy lifestyle.

it seems weird that you would talk about supposed shortfalls of plant nutrition and then in the next sentence talk about cheeseburgers (who considers these healthy?) and multivitamins (which are not considered a substitute for proper nutrition[1][2])

1. https://www.hopkinsmedicine.org/health/wellness-and-preventi...

2. https://www.healthline.com/nutrition/do-multivitamins-work

I consider a cheeseburger healthy.

The custom of serving them with french fried potatoes and a milkshake or cola gives them a bit of guilt by association, but meat, some cheese, some vegetables, and a serving of bread? Don't see an issue at all.

Turns out you can make any meal unhealthy if you include half a pound of sugar.

I'm no food snob and enjoy a good burger as much as the next guy, but are you really calling a leaf of lettuce, 2 pickle slices and a squirt of HFCS-laden ketchup "some vegetables"? Ehh...

That doesn't sound like a good burger per se? I like a couple leaves of lettuce, in August definitely nice slices of tomato, onions grilled or raw, and generally put my six pickle slices in a delicate daisy wheel. I've become a convert to the under-the-meat school of burger 'topping', 2 centimeters of vegetable matter will survive this without the dreaded backslide.

A salad it ain't, but let's not bicker about the meaning of 'some' eh?

A burger with ketchup on it won't pass my lips on purpose, I'll only judge you very slightly for it and you hopefully won't notice. A bit of pan fat or a very thin layer of mayo, mustard on occasion.

There's a lot of evidence that multivitamins don't actually do much: https://www.health.harvard.edu/mens-health/do-multivitamins-...

Any vitamin or multivitamin or mineral supplements can have effects only on people whose diet is deficient in those vitamins or minerals, and only up to a certain daily intake, above which no improvements are likely.

Depending on their diet, some supplements may be life-saving for some people or completely useless for others.

There was some research that claimed that the increase of lifespan gained by eating vegetables was negated by the increased intake of pesticides. In fact, it suggested a net negative.

Regarding B, I had the pleasure of meeting a handful of San [1] elders to record some of their songs. I learned that some of them walked ~10km to meet with the rest of us and did not think much of it. In general their lifestyle is probably a lot less sedentary than mine.

1: https://en.m.wikipedia.org/wiki/San_people

Aren't most studies contradictory ? For one study claiming A you can find another claiming the opposite.

In the 80s/90s there was this constant fear about cholesterol and eggs (perhaps promoted by the cereals lobby?) : did people's habits change? If yes, it was probably because of the monopoly of TV as the main source of "information". Nowadays with internet, every one follows his own little bubble of information.

Yup, according to studies, everything we eat both causes and prevents cancer[1].

AFAICT it's almost impossible to conduct convincing nutrition science. Even if the signs of the effect in observational studies are all in the same direction (usually they're not, see the reference), you still can't rule out many confounding effects. To demonstrate causality, you'd need to force a large number of people on specific diets for a long time in a proper randomized controlled trial, or show very specific bio-chemical reactions to particular food components, or (easier but still very hard) dream up some convincing "natural experiment" or "instrumental variable" to workaround the fact that people mostly choose their own diet.

[1] https://www.sciencealert.com/everything-we-eat-both-causes-a...

I think most nutrition science can be boiled down to 4 rules that most people should follow, and ignore the rest

1. Avoid processed Foods, Learn to cook your own meals

2. Eat a variety of foods

3. Control your portions (especially carbs)

4. Drink more water

Everything else is mostly irrelevant to the normal person. Are eggs good or bad, is Red meat worse than Chicken, etc etc... Who Cares. Eat it all in moderation, while mixing in fruits and veggies all in proper portion

I think it was Food Theory Channel or somewhere that had a video on the amount of influence various industries have had over the "recommendation" by "nutrition science" experts and / or the government, the end result is most "nutrition science" is really marketing not science

I would not even follow these 4 recommendations without a ton of evidence. Yes, they "make sense" because that's what we've been taught since we were children, but are these behaviors good compared to doing nothing?

Well "doing nothing" would be not eating, and pretty sure "Breatharian" is right up there with the flat earth

There was a study on "gluten intolerance" (which unfortunately I deleted) where they did in fact control people's diets in a double-blind way, and check the validity of their symptoms.

Maybe someone can find it, but even with all that rigor, it was somewhat inconclusive.

Due to some fairly serious diet-related personal health issues (obesity and several related co-morbidities), 5 years ago I started closely following nutrition science. In this time, the clearest thing I've learned is that the vast majority of "Nutrition Science" is poor science - to the extent of hardly being science at all.

* If the data is based on diary data, it's noisy to the extent of being nearly useless and no causation can be implied.

* Doing rigorous controlled studies on humans is very difficult and astronomically expensive. Even then, it's incredibly easy for significant confounds and errors to slip in.

* With nutrition studies in general, animal models are usually weak proxies for humans. A large number of significant nutrition results in animals fail to replicate in humans.

* Humans metabolic responses to nutrition are highly variable and contingent on everything from genetic make-up and ethnicity to behavior and environment, etc. So, even in the rare cases statistical causation is demonstrated, it probably still depends on other variables.

* There is a high degree of bias in nutrition science. This includes many funding sources having vested interests from commercial (food lobbies (meat, wheat, milk, etc)) and many researchers having ideological biases (anti-meat vegetarians, anti-meat climate concerns, anti-meat animal welfare, etc)

* Accepting any result as significant requires skeptically examining the methods, statistics and history of the authors and funders.

I agree. And al of that leads to information fatigue. After reading many studies, I'm even worried about "common sense" nutrition knowledge, for example:

* I'm worried about increasing my fruit and vegetable intake, because that will raise my pesticide burden. It is not clear whether the benefits of fruits and vegetables make up for the increased probability of cancer of pesticide consumption. Organic produce is not a solution, as the pesticide burden is even higher.

* Increasing fish consumption of even "healthy" dishes will increase heavy metal consumption. Is it worth it?

* Taking Omega 3 supplements greatly increases the risk of prostate cancer. Is it really worth it?

You can't rely on anything to make dietary decisions for longevity. The best one can aim for is dietary advice to maintain a healthy weight. That, at least, can be quickly proven empirically.

I agree it's confusing. If longevity is a goal then moderation and balance in all things is key. I think there's also decent evidence for keeping your body on the "lean" side of "healthy weight" per the age-adjusted BMI charts through moderate caloric restriction. The evidence is growing for the near-term health benefits of minimizing consumption of processed foods. Primarily all the stuff in bags and boxes that can sit on store shelves for weeks and months and not spoil.

I've also learned to not place much value on "organic" labels. It's expensive and hard to do correctly and not universally better even when it is done correctly. The external verification requirements are almost entirely based on remotely filed "self-reports" with inspections.

>> Mozaffarian discloses in the ATVB paper that he receives funding from Barilla, the world’s largest pasta company—which clearly stands to benefit if meat is sidelined off the dinner plate. (Barilla has invested heavily in nutrition researchers and in promoting the idea that meat as bad for the climate).

Follow the money.

Big Pasta are in on the climate change hoax too? You cant trust anyone.

I was going to quote this exact section, as I felt it was one of the few areas where they let their "we just want real science" mask slip and revealed their consistent "pro-meat" stance.

> Big Pasta are in on the climate change hoax too? You cant trust anyone

Not just “big”. Those Angel hair bastards are in on it too.

What's this got to do with climate change? I thought it was about diet and CVD.

The blog is a front for the meat industry. They try to stick to the areas where they can have vaguely plausible deniability that they're not just attacking everything that would impact meat sales and agriculture subsidies, with the cover that they're "wanting to look at the evidence". But the comment I replied to quotes them having a swipe at a challenge to meat from a non-nutrition angle, which tips their hand a little.

The whole, "we just want the science to be certain" thing is a popular tactic, see for example the Heartland Institute's attempt to have a "Red Team" of scientists pick holes in climate science:

https://climateinvestigations.org/heartland-institute-climat...

Wouldn't surprise me if you could trace this group back to them too.

Ha, didn't think it would be that easy:

https://www.heartland.org/news-opinion/news/follow-the-scien...

For those that prefer Youtube videos:

Is Nina Teicholz right about saturated fat or is she a lobbyist for the meat industry?

https://www.youtube.com/watch?v=VK5ApjZdPEo

lots of links in the description too.

This may be only tangentially relevant, but the author is known to be a pro-meat lobbyist (https://en.wikipedia.org/wiki/Nina_Teicholz).

Could you pull the quote out that says she's a lobbyist? I can't find it, and without it I can't figure out if you're misusing lobbyist to mean "is known to have had this opinion before."

"She was also criticized for being an ally of the meat and dairy industry. ". She's not a scientist (did an "American Studies" degree in college,) just a dirtbag who makes her money shilling for a murderous industry

What on earth is an "American Studies" degree?

Great question

Strong agree. “Lobbyist” has a precise legal meaning and they are required to register with the House and Senate if they are a federal lobbyist and each state has its own registration process if they are lobbyists at that level. It does not appear this person is a lobbyist. Holding an opinion is not enough to make you a lobbyist, nor is expressing that opinion in a published work.

We're not in court. If someone clearly has an agenda then calling them a lobbyist is just fine

Sure, you can argue it’s hyperbole. But if you’re trying to make the point that someone else is sloppy with the facts, it may undermine that for you to make a literally false statement, even if it’s hyperbole. Hyperbole can be hard to detect.

>If someone clearly has an agenda then calling them a lobbyist is just fine

Why not just call them as "having an agenda"? Why do you feel the need to stretch the truth?

words have meanings and should be used accordingly

yes and in this context lobbyist means someone with a clear agenda, not a legal designation. You're the one making up meanings to suit yourself

Definition of lobbying per Wikipedia[0]:

> the act of lawfully attempting to influence the actions, policies, or decisions of government officials, most often legislators or members of regulatory agencies.

A one minute Google search revealed a quote from this politico article[1]:

> She [Nina Teicholz] is also an organizer of a fledgling group that is engaged in a vigorous advocacy campaign to reshape how the U.S. government determines what makes a healthy diet.

I recognize my initial quote didn't validate my claim, but it is nevertheless correct. And it may be true that _professional_ lobbyist need to be registered in the USA, but the term can also (perhaps only in other regions of the world) refer to any person lobbying.

[0]: https://en.wikipedia.org/wiki/Lobbying [1]: https://www.politico.com/story/2015/10/the-money-behind-the-...

"Only tangentially relevant"

would you announce the same warning if they were an anti-meat advocate? I see a lot of bad science and even worse popularization of studies on the vegan and anti-meat crowd.

About TMAO: this is produced when intestinal bacteria consume choline. They release trimethylamine as a byproduct, which is then oxidized in the liver to TMAO. If the liver enzymes are mutated you wind up with "fish malodor syndrome" due to smelling like trimethylamine.

Anyway, any food high in choline will elevate TMAO.

As an undergrad I was briefly involved in an effort to develop an inhibitor of the bacterial enzymes that degrade choline.

"If TMAO is their answer, however, they should really be warning against fish, not meat. Cod yields 65+ times more TMAO than beef, and halibut, at least 100 times more, according to a 1999 study that examined the effects of 46 foods on TMAO excreted in human urine. Carrots, cauliflower, peas, peanuts and potatoes also lead to far more TMAO than beef."

I agree, be careful what kind of fish you consume. I really like sardines (tasty!) and they have much less heavy metals, etc. than larger fish that are higher up the food chain.

Fish should come with CoAs. No ifs or buts about it.

It's far from one study that has found a link between red meat and heart disease.

https://pubmed.ncbi.nlm.nih.gov/?term=meat+heart+disease

Indeed. The original article comes across as really quite biased too. Longitudinal cohort studies can never nail causality but they are quite good at providing measures of apparent risk.

In cardiology, an odds ratio of about 1.2, called tiny by the article, can actually be considered quite large in some circumstances. Very roughly speaking, it's about equivalent to your risk per ten years of age of developing heart failure, or per 20 mmHg of systolic blood pressure [1].

[1] https://link.springer.com/article/10.1007/s10557-022-07355-7

The point isn't that an odds ratio of 1.2 is too small to be important. It is that if the estimated odds ratio from the study, with all its biases, is 1.2, then one can't be at all sure that the actual odds ratio is even greater than 1. (An odds ratio less than 1 would indicate that red meat was protective, rather than a risk factor.)

It's possible for a paper to concur with the majority (or even objectively correct) consensus and still have issues with it's methodology.

Imagine a paper that proved 2+2=4 by surveying preschoolers and going with the majority vote. Correct conclusion, questionable methodology.

For sure. Conflicts of interest are too common in nutrition research, and I think the criticism of this particular paper is laudable.

I simply wanted to point out that there is significant indications from other studies that red meat, and in particular processed red meat, is correlated with heart disease (and cancer).

It's difficult for me to take this blogger seriously when they want to give red meat credit for containing heme iron, which is suspected to be a cause for worse health outcomes.

Yeah, you don't want heme iron if you're an adult, especially if you're male.

At least multivitamin manufacturers get that right (that surprises me). No adult multivitamin contains iron.

Even though I try to make almost all of my meals vegan, I eat two small portions (3 ounces) of non-feed lot organically raised beef a month. I have no scientific basis for my opinion but I think a small amount of beef is good for me. My other occasional meat source is quality sardines, usually sourced from Norway or Spain. Sardines: the “you either love them or hate them” food :-)

I ate no plant-based calories at all for the entirety of 2021 and I ended the year in fantastic shape. Then I relaxed my rule in 2022 and now I'm 20 pounds heavier and don't feel quite as good physically. So I'm just going to resume the strict version of my diet, which seems to work so well for me: 90% beef, 10% eggs and fish -- with no fiber or plant-based calories of any kind.

Still, there are meta-analysis of studies with interesting conclusions.

One example: https://academic.oup.com/nutritionreviews/advance-article-ab...

I am so sick of nutrition science.

Maybe in a couple of centuries it will deserve that description. In the meantime, it seems mostly to be data-illiterate or financially biased spreadsheet monkeys trying to prove things with n=10 and a host of confounding factors. It’s worse than psychology!

She's a shill for the meat industry. Stop believing everything you read

There never has and never will be a good stats-based study on human diet.

We are the most complex things we know of in the universe.

Confounding factors abound. Isolating one is impossible, unless researchers have access to a million identical twins separated at birth and forced to eat a certain diet all their lives, in which case there’s probably a huge human rights crisis going on… and the study would still be invalid because identical twins and authoritarian diet regimes are not the norm.

The only way is to map out the entire chemical pathway in the human body and figure out what is good and bad that way. That will take a very long time; in the meantime, I will eat red meat, butter, animal fat, and eggs like my very-long-lived and exceedingly robust ancestors all did.

One other approach might be to personally try a diet and get regular blood panels and heart scans done. I believe this is the best way.

I don't think handwaving away an entire field of study is going to benefit you in any way, flawed as that field might be.

Living is easy with eyes closed. Dying is too.

Studies with n=10 aren't opening any eyes. They are adding garbage to a crowded information landscape.

Even in the larger studies, there are so many issues. Take the first one about fat and heart disease. Riddled with errors you'll find warnings about in most data science for beginners tutorials.

Or the one about the Mediterranean diet - zero thought given to confounding effects regarding many possible factors. People who eat the Mediterranean diet also live near the sea, and share genetic, cultural, linguistic, political, and economic factors. Sure, maybe it's the fish and olives, but maybe it's another one of the billion things they have in common versus other Europeans or Americans.

This style of studying human metabolism is net-negative. Ignoring it is indeed a benefit. On the other hand, tell me that sugar metabolizes into known toxins, and that's a very different story.

> low-quality type of data that, on the whole, can only show associations, not cause-and-effect relationships.

I have yet to see anyone pull off a long term double-blind experiment on humans--other than the Nazis.

I presume "red herring" is a joke?

A pun.

These thoughts are not entirely my own and I encourage you, along with every one of the commenters here, to read "Food Politics" by Marion Nestle. The dietary advice is generally sound, but the overall message of the book holds true; diet is a political issue. It's a particularly polarizing one too, due to the intimate role that food plays in our cultures, identities, livelihoods and health. It makes sense that this article (along with a hoard of others), is so opinionated and lacks the context to have a well-rounded analysis. I didn't read all the studies, and I'm not going to tell you what to eat, but here my thoughts after reading the article and comments;

- The article mentions data collection issues in nutritional research. My understanding is that, generally, most of this data is collected at an aggregate level (economic I/O, based on overall production and consumption), or via the FFQs mentioned. Self reporting can be unreliable and is heavily subject to biases and the placebo effect.

- The studies linked about TMAO[0] seem to follow a couple trends in nutritional research that food companies rely on to sell more food. First is; diet is holistic, but applying pharmaceutical methodologies to individual nutrients while ignoring the overall dietary habits (again, data collection is hard) can lead to opportunities for companies to market unhealthy food as "healthy". I see that red heart[1] on some of the most sugary cereals, still. Second is; heightening the focus of specific nutrients over food sources in general as a method of dietary confusion. It is more confusing, and more favorable to industry, to say "avoid foods containing cholesterol and saturated fats," than it is to say "avoid meat". Studies that focus on nutrients reinforce these claims and make sound dietary advice inaccessible.

- The article fails to disclose the author's own biases[2] while calling out the "conflicts of interest" that the other studies' authors have with P&G. Commenters are quick to say "follow the money." However, a disclosed conflict-of-interest is not necessarily a bad thing, nutritional professionals need to work and the food industry is a, well... industry that hires food professionals. Do the conglomerates that fund nutrition-research often times leverage studies in bad-faith in order to sell more product? Yes, absolutely. Should you discredit all nutrition research backed by a corporation, probably not.

- Dietary advice is intended for populations, not individuals. If I were to say something like; "avoid having more than 24g of sugar a day"[3], I'm saying that targeting 97% of a population. This advice is also influenced by the goals of the organization/administration[4] releasing the advice and overall health concerns for the population. Most of the leading causes of death, in the United States, are linked with overconsumption. As an individual, genetics and lifestyle play a role and shift your needs. A person will probably need more than the recommended amount of salt on the day-to-day than average if they exercise.

On a separate note:

@dang I'm tired of reading political op-ed pieces that quote bad studies as proof of... whatever, especially those related to health. Is there a blocklist and can (unsettledscience.substack.com)[5] be added to that list? Also, out of curiosity and possibly related to this submission, what sort of mechanisms does HN employ in order to moderate submissions from suspect users? Thanks for all you do by the way.

[0] https://en.wikipedia.org/wiki/Trimethylamine_N-oxide

[1] https://en.wikipedia.org/wiki/American_Heart_Association

[2] https://en.wikipedia.org/wiki/Nina_Teicholz

[3] https://www.hsph.harvard.edu/nutritionsource/carbohydrates/a...

[4] https://en.wikipedia.org/wiki/Dietary_Guidelines_for_America...

[5] https://news.ycombinator.com/from?site=unsettledscience.subs...

I think the reason why academia is trying so hard to demonize meat is because they have pushed grains so hard for so many decades and now the truth about grains and blood sugar is coming out...which makes them look bad

an excessive consuption of refined grains is bad, eating the right amount of whole grains is solely beneficial

I wish that we stopped saying things like ‘eating this and that is beneficial’ or ‘good for your health’.

You know, consuming calories is immensely beneficial and good for your body if you haven’t had a meal for a day. Doesn’t really matter if it’s refined grains or whatever.

Consuming some vitamin-rich whatever is healthy for you if you’re low on those vitamins, otherwise it’s calories and a bunch of work for your liver.

There’s stuff that is objectively bad for your health, almost no matter the circumstances. Like some fried sugar-rich dessert, unless you’ve been starving for a few days it’s probably going to be bad for you on all accounts.

That's a vacuous argument. It's true for literally anything.

an excessive consumption of water is bad, drinking the right amount of clean water is solely beneficial

an excessive consumption of eggs is bad, eating the right amount of eggs is solely beneficial

an excessive consumption of toxic sludge is bad, eating the right amount (0) of sludge is solely beneficial

The question, of course, is what is the right amount and is it more or less than what most people eat.

> true for literally anything

Pedantic: no. It’s true for everything that is safe or beneficial to consume. There is no “right amount” of lead or plutonium in your diet.

Even more pedantic: The right amount is 0. I did include that case in my answer.

Touché!

This is such a disingenuous reply.

We are not talking about cyanide here or some strange nutrient that you can overdose if you're not careful. A serving of whole grains every day (just read the back of the box if you're unsure what the quantities are) is solely beneficial for you and unless you have a medical condition you simply can't go wrong.

I was trying to be flippant, which is fun for me but obviously not very helpful, so let me rephrase my answer.

I agree there is a non-zero amount of grains that is healthy to consume, but your answer doesn't say anything about what that amount should be, and as such just states something that is pretty obvious. It would improve your answer a lot if you stated which quantities you are thinking of, and even more if you include sources.

From your original comment I honestly was not able to tell that your recommendation was to eat cereal daily in the amounts recommended by the back of the box.

I gave up on nutrition scientists a couple of decades ago.

I've taken the view that my stomach is my best guide to what I ought to eat. That's convenient, because jamming food down my throat that I don't actually fancy makes me gag.

I end up eating a mix of veg and red (mostly) meat. The veg consists mostly of grains (pasta, rice, wholemeal toast) - I don't much care for rabbit food. I eat red meat daily, but in tiny quantities. I have a very small steak once a week or so. The steak isn't small because I'm scared of red meat; it's small because that's how much I want to eat. Tonight, I will eat Brocolli Mornay (broccoli-cheese).

I eat refined sugar. Not much, but it doesn't frighten me; the sugar in refined sugar is either the same as the sugar molecules that occur in all foods, or suffers the same metabolic destiny (it's either excreted, or turns into glucose). I am liberal with butter when cooking; fat makes food appetising, and it's hard to make tasty food without using fat.

I'm overweight, but the main reason for that is that I drink a lot of booze - not that my diet is no good.

I think nutritionists should focus on teaching people how to listen to their stomachs more, and to nutritionists less.

You may be right, you may be wrong but with respect, if you can't supply references to peer-reviewed studies to support your contentious assertion then why should anyone believe you?

> you may be wrong

You can't be wrong if you say that eating excessive amounts of X is dangerous, but eating the right amount of X is optimally beneficial. You can be completely vacuous, but not wrong.

Are you saying that eating the right amount of something is good and eating the wrong amount is bad?

There’s science that shows whole grains are not good for you, just as there are studies showing they’re good for you.

Citation needed.

There is no "academia" conspiracy. Academia is made of people. Most of those people just go about doing their work, like everyone else in every other job. A few commit fraud, and a few conspire with others with others to commit fraud---just like every other job.

There is no academia conspiracy, but have you seen Dopesick?

Exactly how was academia involved in the opioid crisis? That was mostly doctors and drug companies with health insurance complicity.

Unfortunately meat is clearly bad for you in at least one but probably many ways. The most compelling evidence to me is that carnivorous animals have higher rates of death from cancer, see fig 2 of this fascinating study: https://www.nature.com/articles/s41586-021-04224-5

"Carnivorous animals have higher rates of death from cancer"

Say hello to Crocodiles :)

https://www.cell.com/heliyon/fulltext/S2405-8440(21)02697-9

The study I cited was of mammals. We aren't going to learn anything useful from the lifestyle of cold-blooded reptiles. For one, their metabolic rate is much lower.

Likewise comparing ourselves to obligate carnivores, or obligate herbivores is also less useful. Ideally you'd want omnivores that for one reason or another excluded meat from the diet, or did not. Right?

Not really. The key question is whether meat is carcinogenic or not. If you eat less of it, sure it will be less carcinogenic, but it won't be suddenly good for you.

There seems to be a lot of people who want to eat meat and also deny that it has various adverse health effects. The evidence is pretty clear, that's all I'm saying. What one does with that information is up to the individual. I don't do anything with it.

but you can't blanket say meat is carcinogenic. If we acknowledge that meat has no link to cancer in alligators or sharks, then we need to question if it is because of animal, the meat, or both. Likewise, if mountain lions have higher rates of cancer than deer, is it the animal or the food? Likewise deer are eating acorns which are very high in antioxidants. So its another variable. Do mountain lions have higher cancer rates than a wild hog? That is an interesting question. As far as my bias from what I want to do. I want to eat ice cream and drink scotch all day, but I won't argue either are healthy. Alcohol is generally listed second after tobacco as a cause for cancer in humans. I really just don't think the link between meat and health is well established in humans, or even if it is the same across human variation.

Does that study only look at zoo animals? I would assume carnivorous animals get far more exercise when they have to hunt, chase, and kill their food than when it’s given to them. That confounding factor alone might be large. I’ve been wondering about the relation between nutritional excess and cancer, can’t recall ever seeing this studied.

Yes, they are animals in human care. But the fact is there is a difference between carnivores and herbivores across various species and animal lifestyles, which is strong proof that meat is carcinogenic. What factors mitigate this in the wild are largely irrelevant. You can smoke and exercise and be a bit better off, but that doesn't change the carcinogenic potential of cigarettes.

> What factors mitigate this in the wild are largely irrelevant

Why? If we find a link indicating exercise reduces or eliminates the cancer risk associated with eating meat, then it would just show another option for behavioral change to produce positive outcome. More options is not a bad thing.

It’s a bit like studying how to reduce your chance of lung cancer from smoking if you want to keep smoking. No mitigating factor will eliminate the risks from red meat, except not eating it. Also lifestyle or nutritional mitigation factors are difficult to study, and it’s never clear if they apply to a given person with a particular genotype and environment.

This is only a study of raw meat consumption, which is comparatively rare among humans. If it turns out — and this study acknowledges this limitation — that the predominant causal agent here is cancer-casing viruses, that would have pretty irrelevant impact for humans.

There are so many confounds here that it’s hard to draw conclusions for humans except maybe what’s worth future study.

FWIW, I have no horse in this race either.

The 2012 plenary session in the biggest cancer conference in the world was about cancer causing viruses in red meat that wasn’t cooked to a certain temperature. It hasn’t really panned out since. In any case, the bottom line remains that red meat can cause cancer. Preparing it a certain way might reduce the risk but not to zero. Humans still eat a lot of non-virally sterile meat. Yes we can spend the next 100 years studying it, but what should one have for dinner tonight? The answer it seems is probably not red meat.

I mean…maybe? But it depends on the effect size, really. And the virus thing is just one possibility among many.

Even if red meat increases your lifetime chance of cancer even by a few percentage points, then one should probably spend more effort reducing other risks, like moving further away from the highway, filtering your air, etc. Definitely don’t fry anything, and probably stay away from grilling too?

Likely depends what else is in your diet too.

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