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Comment by Johanx64 | Hacker News Reader

Bollocks, physics is an actual scientific field and aerospace engineering is actual engineering (compared to say "software engineering" where it's engineering in name only), similarly there's barely anything scientific in the "nutritional science".

If you have a real scientific background and real engineering background you are way more likely to do a proper job.

It frustrates me that people think nutritional "science" is a serious scientific field. And that the "nutritional scientist" is somehow better equipped - they have barely done any real science a single day in their life.

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Would you have a physicist would self-taught medicine as your doctor? Of course not.

While a scientific or engineering background might demonstrate capability to understand another scientific field, that doesn’t replace the near decade of education people in that field have.

I would, compared to 8 out of 10 doctors I’ve met.

A dedicated physicist who self-taught medicine would allow hoofs to be zebras, not horses, some % of the time.

False equivalency

Doctors need practice in the hospital and do an excruciating amount of rounds surrounded by senior experts.

Nutritionists? No.

Given a nutritionist who has studied the books and gotten a degree and a physicist who has studied the books and hasn't gotten the degree I would be hard pressed to choose the nutritionist

I am someone with a computational physics background who is coupled with someone who is training to be a surgeon. We lived together during much of her medical school, and thus, are constantly around medical professionals.

I would absolutely trust a physicist (who has done actual empirical lab work) who has deeply studied a problem in the nutrition space over someone conventionally trained in nutrition.

You may be stunned to see how little numerical sense so many in the medical field have. And as someone who grows medicinal plants and follows that literature closely, I read tons of papers in that space. It is full of experimental design flaws and dubious correlations.

I have worked on a medical device that went through clinical trials.

They have a point. It's easy to come with your high IQ and miss some obscure subtle data that people in the field learned the hard way. Sure the man is capable of understanding it quick and even do more.. but it's too easy to get carried in your own newcomer theory.

What makes you think you're right about any of that? Do you have any evidence to back up your (crazy) theory that an entire field of study isn't real science?

Cause from where I'm sitting, nutritional scientists do plenty of real science - studying a very complex problem that poses a lot of challenges to experiments, and still coming up with a lot of great results that teach us tons about nutrition.

Most people that criticize the field do so because they read a bunch of articles. Or because they're in the world of hard sciences, and are simply arrogant enough to think they know better than everyone else, even in fields they've never studied.

So what makes you an authority in defining what’s a scientific field? Care to share some actual data?

You don't need to be an authority to see how the majority of human nutrition science is barely a step above junk. Pick any journal in the field and go through the last few issues. You'll mostly find observational studies with subject reported data (known to be inaccurate). Very few long, term randomized controlled trials with meaningful endpoints.

It is worse than junk. most junk science is harmless, but bad diet advice can hurt your health.

If you can rigorously test your hypotheses in an experiment, it is a scientific field.

If you can't, or won't, it is not a scientific field.

There have been tons of nutritional experiments which are extremely rigorous.

Unfortunately, like most fields it’s the junk you read about because rigor is slow/difficult/expensive and therefore less common than BS. Just look at say fusion research and all it’s seriously flawed experiments.

And tons of nutritional experiments demonstrating the exact opposite result, that are also “rigorous”.

Sure, human biology is (hundreds of) orders of magnitude more complicated than say going to the moon.

But at this point in 2024 we “know” a lot more about physics than we do about nutrition.

And maybe that’s because physicists, when faced with contradictory data, keep digging until they figure out the basics once and for all.

That's just not true. We know a lot about the basics of nutrition. Actual nutrition scientists mostly agree on lots of different things.

The problem is that the public doesn't want to hear it, so the media keeps running articles that make it simple like "nobody knows anything". Which is just plain false.

Care to list some of the basic tenants of nutrition that are widely agreed upon?

About the only things I see as generally accepted are to eat a varied diet (whatever that means), keep total consumed caloric content near the amount expended, eat at least the RDA of micronutrients, and drink enough water to avoid overt dehydration.

And we're not even sure what the RDA should be, half the time.

At a practical level nutrition isn’t generally a problem, but that says more about the human body / food than the lack of scientific knowledge.

There is a long list of things that cannot be synthesized by people and must be consumed. (Elements like Potassium as well as specific nutrients like Vitamin C and Thiamine being well known.) There’s a longer list of things than can be synthesized but should largely be consumed ex:

Linoleic acid (LA), an omega-6 fatty acid, and α-linolenic acid (ALA), an omega-3 fatty acid, are considered essential fatty acids because they cannot be synthesized by humans.

The long-chain omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), can be synthesized from ALA, but due to low conversion efficiency, it is recommended to consume foods rich in EPA and DHA.

There’s also a lot of basic facts that get complicated when you dig into them. For example calories produced by burning foods isn’t 1:1 with the calories available to people. Cellulose for example burns but is effectively indigestible. One way to investigate this is to have some eat something and then burn their poop, followed by many studies that do so for various reasons.

There’s also a lot of nutrition science that straddles the line with medicine. Thus there exists many specialized diets for various conditions etc.

I'm not a nutrition scientist, so obviously not at all an expert that can probably chime in with some more findings.

But generally - yes, afaik there's mostly a consensus that total caloric intake is the driver of amount of adiposity, that maintaining a 10%-20% body fat percentage (for men) is optimal for long term health, that most diets are close from a health and fat-loss perspective - meaning, amount of adiposity is the main driver of long-term bad health, especially as compared to individual ingredients. There are some things that are known to be specifically problematic, e.g. trans-fats, at any amounts. And there are healthier and less healthy foods, some of which we know - but total caloric intake is the only driver of body composition, and a bigger driver of body health.

Most of this is basic - probably because, as I said, I'm not a nutrition scientist myself so only understand the basics myself.

That said, a large part of the population doesn't even understand these basics either, preferring to constantly talk about and argue about specific diets, keto vs. vegan vs. whatever. And science mostly has that question covered, as far as we can tell right now.

For a more in-depth take on this from someone who actually is an expert, I recommend videos by Mike Israetel:

https://www.youtube.com/watch?v=7FM9VAH_EXw&list=PLyqKj7LwU2...

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

There’s probably a grey area for social sciences like economics.

I also tend to think there’s real nutritional science but it’s being drowned out by all the snake oil.

Snake-oil and moralizing. Dietetics suffers from the same issue that mental health does: there's an underlying stigma that causes people to inflict a moral judgement on the ill; fat people - or so the old line of thinking goes - are immoral. A shocking number of people, including many doctors and scientists, view diabetes as a "fat people disease," and that diabetics are in effect being punished for their gluttony. This isn't always a conscious bias, but it has very negative effects.

It reminds me of the studies they've done in Canada and the US about how natives (American Indians) die a lot of the time in the ER because they're immediately written off as alcoholics or drug-addicts, and so their complaints are evaluated through the lens of "this person just wants opiates."

It’s been said that iteratively developing a software based solution is like testing a hypothesis and seeing what works

Where did this definition come from? Did you just make it up? It excludes all of mathematics and most of astronomy, for example.

Well on some contexts maths is apart from science, see e.g. the STEM acronym :)

People generally consider, although this is not universally agreed, that math isn't science. To me the distinction matters, although it's fairly subtle.

This is underscored by frequently cited articles, like: "The Unreasonable Effectiveness of Mathematics in the Natural Sciences", in which math is treated as separate, but intimately related, to natural philosophy.

I think you can do math without science, but you can't do science without math.

Let’s pretend all of that is true. How does a background in the “hard sciences” with experiments involving materials that can’t make their own decisions prepare you for a field with experiments where you have to account for the fact that you can’t imprison your test subjects for 6 months, and that when they are on their own may not follow the experimental protocols (or even lie about that fact)?

https://xkcd.com/793/

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