Hacker News Reader

> Of course if you convince the populace that fat is evil and you can avoid weight gain just by avoiding dietary fat that food companies will respond accordingly.

But was it really scientists who convinced the populace that fat is evil? Or was it journalists, public commentators and business interests who convinced the populace that fat is evil, based on scientists' (retrospectively mistaken) results suggesting that substituting dietary fat in favour of carbohydrates was likely to improve certain health conditions?

Ancel Keys was a scientist but at the same time he enjoyed his influence and fame including being featured on the Times magazine cover. He personally contributed to popularization of his diets, then and ridiculed and marginalized Yudkin and low-sugar camp.

Portraying scientists as selfless truth-seekers is largely inaccurate. They are people after all.

Scratch the surface and people are pretty much the same.

I think part of this is that a lot of “scientists say” advice that makes it to the mainstream is mostly a media creation.

Somewhere down the trail of sources is a scientific paper measuring the affect of a difference in X in Y specific population.

Then the magazine / newspaper / newsblog article comes out as “Is X killing you? Scientists say cut it out of your diet to live longer!”

And of course the population ends up being dismissive of “Science(tm)” when the articles on their Facebook feed alternate between “Scientists say X is good” and “Scientists say X will kill you” from week to week or month to month.

> I think part of this is that a lot of “scientists say” advice that makes it to the mainstream is mostly a media creation.

The article here points out this was not just a case where a paper was released that the media then ran with. According to the article, this guy had "dozens" of interviews making his point, and heck, he was science advisor for the "United Nations’ Trillion Trees Campaign". He himself fanned the flames of this media narrative.

Agreed. There's still a difference between saying that planting more trees is good for the climate, and policymakers running with that and planting trees with disregard to all other science and research on ecology and ecosystems.

It's like advocating for feeding school children because kids who aren't missing meals get better academic results, but then finding that schools are feeding them nothing but oreos because you didn't specify in every interview that they should also follow all of the other recommendations on proper balanced nutrition.

I think this demonstrates the differences between research, media, and policy. A scientist working in policy should ideally know and account for these differences.

Maybe scientific publications should have a layman-readable summary where the authors specifically say This is what "Scientists actually say" in this paper. Those dry, still-very-technical "abstracts" are no good. 54% of American adults have a literacy below sixth-grade level. The abstract still requires interpretation by the magazine / newspaper / newsblog article where inaccuracy, hype, and clickbait seeps in.

You missed the part where scientists often eagerly seek media attention to push their agenda, get more funding or for vanity alone.

this always happens on the cartoons so it must be real

This is literally what happened in the linked article

We have a word for that: anecdata

There are, dunno... lets say "one million" of scientists in this planet?. I don't see one million of scientists all the time on TV or doing this things on the labs

"oh, but he has a ponytail!" this is the type of things that media are seeing and hearing while people explains their job.

Finding a journalist that will not try to mock you or abuse your time, is like finding an opera singer dressed as a walkiria inside a clam

What's the -ism for people who believe tHaT nEvEr HaPpEnS until there are at least half a dozen meta-analyses on the subject? Just because nobody's published on the phenomenon doesn't mean it's not repeatedly observed.

> I don't see one million of scientists all the time on TV or doing this things on the labs > Finding a journalist that will not try to mock you or abuse your time, is like finding an opera singer dressed as a walkiria inside a clam

Peak anecdata. I've spoken to several journalists - all of them pleasant and none of whom mocked me or abused my time. I don't see millions of journalists on TV mocking people.

That is part of it, but a group of scientists also know how to manipulate the media well and get a lot of attention on their theories.

Linus Pauling won a Nobel prize, twice. He got most of his attention though for spreading the idea that vitamin C is a cure for everything. He gave a lot of interviews in a lot of different places spreading that message.

In physics they are still trying to recover from 20+ years of string theory claiming they are just around the corner from a theory of everything. Smart people have done a lot of interesting work in string theory, but none of it has ever been close to a testable hypothesis. The people though knew how to use the media to spread the message and get funding - not only taking funding from more promising branches of physics, but when the funders caught on drying up the total physics pot a bit.

This exactly. Most academic papers (Nature, Science notwithstanding), don't make bold claims. Rather an effect is measured, cause isolated with sone experimentation, some inference, and reported on. "Seems to be" is the dominant phrase.

So you 'loathe' not knowing every possible consequence of saying a true thing?

That seems a little overly hysterical.

I think the OP is more about "obvious first order consequences" than "every possible consequence."

If there was an honest —albeit mistaken— belief that fat was worse for health than carbohydrates, the introduction of fat-free biscuits would be an ostensibly positive first order consequence, regardless of their high sugar content. It is only when the knowledge of the health effects of dietary fat and sugar, as well as their proportions, is revised that we know that this first order consequence was obviously negative.

Except scientists were literally paid by "Big Sugar" to point their finger at fat as the culprit.

https://www.npr.org/sections/thetwo-way/2016/09/13/493739074...

https://www.nytimes.com/2016/09/13/well/eat/how-the-sugar-in...

The problem I see with the US is that companies have been allowed to influence almost all sections of society. I'm pretty sure the scientist that time knew that fat on its own is not the issue(wet to getting more fat) when calories are controlled. That bit of nuance seems to be lost over time. I remember reading about how the sugar industry went on a PR campaign talking about how fat is bad and sugar is fine. If they was some pushback to this things might have been different

> I'm pretty sure the scientist that time knew that fat on its own is not the issue(wet to getting more fat) when calories are controlled.

The calorie model was well established, so yes, they knew that you'd still get fat if you ate as much calories.

But both scientists and doctors absolutely did believe that reducing fat consumption would directly reduce the incidence of heart disease regardless of body weight. The same thing happened later when it was believed that consuming cholesterol, or even later LDL, would increase the risk of high blood cholesterol and thus atherosclerosis. This led to things like doctors and large medical bodies recommending margarine instead of butter as a health food(!).

There has been plenty of terrible advice coming directly from nutrition science and medical bodies influenced by it. Most likely even current advice will turn out to be nonsensical as we learn more.

Exactly. Planting a tree should be good independent of anything the human does. That's kind of the point of science. We want to isolate effects and study them independently. And we want to study these effects independently of any political spin. Then society can make a smart decision.

I still use a food pyramid as a reference to date! Is there any particular food pyramid you’re thinking of? The idea in itself seems very reasonable to me.

Read the book “Death by food pyramid”. The pyramid you know is almost entirely wrong, carbs should not be the base, and fats should not be the tip.

The pyramid I know? For what it's worth, the pyramid shown on the cover of the book you mention is quite different from the one I know best. The one I use goes like this, from base to tip:

  1. fruits, vegetables, lentils, wholegrain bread
  2. rice, oats, fish, oil, margarine, yogurt, milk, pasta
  3. meat, eggs, cheese, white bread
  4. sugar, candy, sausages, pastry, butter

I have no doubt that it is possible to build a food pyramid wrong, but again, the idea seems entirely reasonable, so it should be possible to build one that's actually useful. What I'm curious about is if this belief is fundamentally flawed and food pyramids are just a poor way to convey nutritional advice (for a reason I'm not seeing at the moment), or if the idea itself is perfectly fine and all this criticism is being made with regard to some particular misguided pyramid (which I might not be all that familiar with, seeing as multiple variations of 'the pyramid' exist, some of which might be way better than the others).

My apologies, shouldn’t have assumed. Usually when people talk about “the” food pyramid being wrong, they are referring to the USDA version from the 90s [1], with bread/rice/pasta at the base, that ended up being replicated in textbooks all around the world. Most countries have moved on since, but the effect in popular culture remains.

[1] https://cdn.britannica.com/12/73412-004-8D081488/grain-produ...

I'm specifically referring to this food pyramid, https://en.m.wikipedia.org/wiki/Food_pyramid_(nutrition)#/me..., which was well-known by the US populace at large (as well as taught in schools) in the early 90s. There were subsequent US food pyramids and then a new "MyPlate" program in the US after that, but none that were as widely known/discussed as the original one.

The basic problem of the original food pyramid is that the base is essentially "tons of processed carbohydrates" (flours, bread, pasta), while it says to minimize oils and fats.

But I think the biggest crime of the original food pyramid, and honestly much nutrition "science", is that it was not scientifically based. There were never any studies that said, for example, that mono-unsaturated fats were bad for you (the opposite is true), but the food pyramid made broad assumptions without any actual studies to back it up.

The flip-flop on dietary cholesterol is another good example. There is evidence high LDL in the blood is associated with higher rates of cardiovascular disease, but never evidence that eating cholesterol leads to higher LDL levels, except in certain genetic circumstances. For decades nutritionists told us "eggs are bad for you" based on this theory without any evidence to back it up.

Soooo... scientists should not release their results? Scientists should make policy? Or what?

Some science gets done to gather metrics. Those metrics get oversimplified into broad public advice. Following this advice to the letter circumvents both the public messaging intent and the related science. "Do what we meant not what we said." I would put most of the blame on the science communicators / policy advisers. But it also doesn't help that there is a large mismatch between how definitive nutritional science is vs how hungry for science-based nutritional advice the public seems to be.

Much of this nutritional "science" has been made into public advice by large swaths of the medical establishment, by people's own doctors, by public health authorities. We're not talking about advice people took from reading Reader's Digest or some health magazine.

Scientists should stop trying to make policy off the back of their studies, which are too narrow to provide a full picture of something like food and environmental issues.

The problem as as the public I need to have/create useful policy. Studies are a lot better than my "gut feeling". Sometimes my "gut" is right, but sometimes I conclude heavy objects fall faster than light objects.

Thus I want scientists to study things and help figure out what policy will make the world better.

The scientist in this article didn't just "release his results", nor did the anti-fat scientists of the 90s just "release their results".

First, in both cases the science was actually bad science. Here there were tons of other scientists that said their estimates were overrated (and the original authors later admitted as much), and in the nutritionists case there were never any scientific studies that would lead to recommendations against consuming unsaturated fats (there was just an assumption that since fat is denser in calories, cutting back on fat would result in weight loss, which has now been thoroughly debunked).

My point is that if you make a "scientific" recommendation, of course companies will latch on to whatever part is in their economic benefit. That shouldn't be a surprise. So to come back later and say "I didn't think company X would do Y based on my research!" means you're either lying or an idiot.

If instead of going around shouting in tons of interviews about how planting trees can offset carbon emissions, which is what this guy did, he had gone around advocating for preservation of existing habitats and reduction of fossil fuel use (which is what he's doing now), this whole thing could have been avoided. This guy doesn't get a "oh, it's not my fault" pass just because he ignored the obvious consequences of his advocacy.

Fossil fuel companies don't have emissions, their customers do. When I drive my car, it's me emitting CO2, not the gas company.

But I know it's expedient to shift the blame to the oil companies.

A problem with science vs popular opinion is that science is gathering new knowledge that justifies reevaluating our old (often simple) patterns and adopting new (often more complex) ones. But people are resistant to change and also prefer simple solutions. I haven't seen any general solution to that.

The cases you cite began with simplified solutions, to try to get people to adopt change. Then it turned out that the solutions were actually oversimplified and harmful without broader context.

What should we do when clearly doing nothing is also a problem?

Could write laws as if() else() foo = bar*42 with the variables obtained from scientific studies. You cant glue them together directly but we could periodically randomly select qualified scientists, force and pay them to review the literature then set the variables for that period.

Not that we should get rid of manual tinkering/rewriting/expanding/deleting laws but to have some more gradual transitions.

Say sentences starting like "Since we know it is eating fat that makes you fat[committee VI] it is now forbidden..." Would be automatically suspended if committee VII does not agree to elevate the hypothesis to that level of certainty.

A bit like a legalese code of law generator.*

> What should we do when clearly doing nothing is also a problem?

For nutrition at least, doing nothing to try to influence eating habits from the 50s or so would have almost certainly been better than what we have done. Probably better than current recommendations are as well, given the history and given the abysmal quality of nutritional studies.

> A good analogy to me is the "anti-fat" nutrition crowd in the 90s

No need to go till 90s. We have now anti-sugar.