At a minimum, you would need to force people to eat a certain diet, with no option to sneak in a few snacks while the researchers aren't watching.
And you probably need to do this for a whole generation (ie. from birth until death) to really get good data to prove that diet X leads to better outcomes than diet Y.
Large-scale high-quality research on humans isn't possible.
https://www.scientificamerican.com/article/records-found-in-...
But they certainly have some advantages over, say, studies based on food frequency questionnaires.
I disagree. What seems simple enough may actually be the last piece to be figured out. We don't have as much knowledge about the fundamental blocks, atoms, as we would like, but that has seldom stopped us from building sophisticated applications using it. If anything, us not figuring out could only be an indication how inherently complex the nature can be.
In the early days of AI, before the winter, people thought that getting computers to play chess would be hard but walking or recognizing faces would be easy. Turns out that complexity is often not where we expect, except for a general tendency for more complex more macro-level things to be harder. Even then there are exceptions, but nutrition has not shown any signs of being one.
Associations with cancer risk or benefits have been claimed for most food ingredients. Many single studies highlight implausibly large effects, even though evidence is weak. Effect sizes shrink in meta-analyses.
Is everything we eat associated with cancer? A systematic cookbook review; Jonathan D Schoenfeld 1, John P A Ioannidis. 10.3945/ajcn.112.047142
Eating less reduces your need for food ('adaptive thermogenesis'), and hence total oxidative stress load. This almost certainly reduces your risk of cancer and also more than likely slows aging. [4]
[1] https://journals.physiology.org/doi/abs/10.1152/jappl.1958.1...
[2] https://pubmed.ncbi.nlm.nih.gov/27136388/
This entire article reads like someone only understand the field by reading clickbait headlines about nutrition (“Eggs are good for you now”) and then assumes the scientists and journalists are one and the same.
It also sets up a lot of straw man arguments that rationalists are likely to come up with but that you would hear from actual science, such as the idea that they’re searching for a rationally perfect diet.
I don’t know what’s going on with that site but it’s not really a good resource. Identifying some areas where the science isn’t clear or where observations has changed and then trying to use that to dismiss an entire field is a classic anti-science trope used by people who prefer to feel superior to scientists and to downplay science. It’s most commonly used on topics like climate science or anti-vaccine research.
Only if one looks any deeper they find that the journalists printed the summary provided by the researchers. That they accurately captured the message the researchers were pushing. Researchers want eyeballs, and they want the funding that comes with attention, along with the personal prestige, and this has proven incredibly corrupting. Add that a pretty good percentage of nutrition research is funded by parties with deeply conflicted interests.
In any case, the site is largely accurate. The nutrition field has made extraordinarily little progress. Right now, in 2023, pretty much the only solid nutrition conclusion is "don't eat too much. Eat a variety". Almost everything else does not stand any scrutiny at all. It seems entirely valid to dismiss the nutrition field given the past forty years.
It's actually interesting watching a subreddit like /r/nutrition. The place could as easily be people discussing their healing crystals and chakras. That's where we're at right now.
What is your point? Are you suggesting that they are not to blame? They certainly write the articles. They may even be a part of juicing up the headline sufficiently to become a perfect clickbait.
Only few months ago, an article was written about recovering in 'no work' spaces, which happened to include cars. Fortune title? Scientists say car is your meditation spot ( I am paraphrasing a little since I am quoting from memory ).
When they're literally quoting almost verbatim the claims of the researchers, no they aren't to blame. And the vast majority of the time you see an article with some breathless claim, it is capturing the essence of the research summary, or the press release put out by the university or think tank.
See, journalists like their jobs to be easy. They generally aren't spinning whole wool. As Graham's The Submarine describes, often they're basically reprinting something sent to them with minor wording changes.
That's my point. And my point was amply clear in my original post. Blaming the journalists is often nonsensical sophistry. A hail mary to try to recover some semblance from busted research, as if it's the messenger who is to blame. The worst part is that the blame the journalist people create a vacuum in which even worse sources of information grow.
Not sure the vaguely remembered, poorly communicated anecdote (which I can find zero references for) supports your point.
You do have a point.
I feel vaguely attacked. See article[1]. Original title that you can still see in search engines, because it was only changed after pushback:
>>You need to detach and 'psychologically recover' from work, professors say. The solution: commuting<<
What I appear to be getting from your post is: 'No one is to blame. No one could be held liable for their actions. It is all sophistry.'
Which is funny, because I am willing to agree the system has perverse incentives to mess with things at numerous checkpoints, but you cannot realistically claim this, because researchers ( and indeed all humans ) like their jobs easy as well.
[1]https://fortune.com/2023/02/02/remote-work-why-do-i-miss-com...
I am quite specifically hanging the blame on researchers who are perpetrating junk science. Most observation / survey based science is junk science. Most "study of studies" research is junk science. It's lazy science to get media attention, and the more salacious or contrarian the outcome, the more appealing it is for some subset of researchers.
This isn't an attack on science or scientists in the whole, clearly. But when you see some breathless article exclaiming that eating an olive pit twice weekly makes you live twenty years longer, blaming the columnists seems foolish. In almost every case they're simply repeating the claims of bad science.
I am not automatically disagreeing, but that is a pretty strong claim. I am relatively certain that a well chosen survey participants ( that are not mturk or local body of students unless actually applicable to the study ) could make for a decent study. I can't really opine of observation, but on the surface it strikes me as a very strong claim as well.
<< But when you see some breathless article exclaiming that eating an olive pit twice weekly makes you live twenty years longer, blaming the columnists seems foolish. In almost every case they're simply repeating the claims of bad science.
And this is where it gets tricky. Do editors/publishers merely parrot it or add media cycle friendly spin on it?
<< I am quite specifically hanging the blame on researchers who are perpetrating junk science.
I think I am willing to mostly agree with that statement in a sense that they ultimately responsible.
That said, it is hard for me to believe that editors/publishers would publish it if standards were a tad higher and not chasing attention.
The parent comment is trying to dismiss an entire field and also preemptively dismiss new studies based on some past anecdotes.
It's the exact same trick used by climate science deniers who go back and cherry pick some old studies where the conclusion changed: Pick some old studies where the conclusion changed, announce that science is fallible, then dismiss the entire field.
It's ridiculous logic to anyone who understands how science works, but it's very appealing to people who like to be contrarian.
If they're observational or survey based studies, they should be dismissed generally, or at least given incredibly little attention. Even worse they're usually 2nd order "I took some terrible observational studies, put them in a pile, and now I have a study of studies" bit of bunk that is a bit like CDOs: Just layer the junk and pretend it has value all together. We have decades of doing this now to have learned that it is extremely low value, and simply repeating the same pattern again with new biases and assumptions is not going to improve the situation.
Nutritional studies are really, really hard, short of creating concentration camps and assigning diets to sections for decades.
If you were studying physics by doing a survey on what people's opinion of gravity is or what their recollection of their acceleration rates for the past year, you'd probably not have great results.
We've looked for those answers, and they don't exist. But the media has to deliver them anyway, so they do, and they cherry-pick and misinterpret studies to do so. Some attention-hungry researchers cater to them, and a lot of doctors with more ambition than shame try to get rich selling books and supplements.
We're not limited by our nutritional knowledge anyway. When it comes to eating and health, we have much bigger problems to solve than the current nutritional unknowns. Most individual members of society suffer from ignorance and false beliefs that are way, way worse than the uncertainties and false results in nutritional science, and most people feel psychologically incapable of acting on what they think they know anyway. Any forces trying to educate and empower people are massively outgunned by shamelessly unprincipled hucksters filling the air with whatever noise they can sell on one hand and blatantly evil food industry marketing on the other.
US nutrition advice is basically just a contest in how many carbs you can eat.
A very generic counterpoint.
Nutritional science has no such trophies
I think the basic Michael Pollen formulation, which is "Eat Food, Not Too Much, Mostly Plants" has held up pretty well.
Why do you think there is any confusion about the overall health effects of eating meat, eggs, and dairy? With $ billions at stake - of course they find unethical ways to find some statistical anomaly to make their products good along some narrow dimension - and then have their money-funded media stories amplifying the lies.
I strongly recommend https://nutritionfacts.org/ - a non-profit focusing on finding the signal through the noise.
https://sciencebasedmedicine.org/death-as-a-foodborne-illnes...
Because I have genuinely no idea whether you think that meat, eggs, and dairy have positive or negative overall health effects.
Meat consumption has reliably been found to have bad effects on health.
You're pretty much saying that, as long as you ignore the studies which you consider to be illegitimate, then the outcome of the science is clear.
The fact of the matter is that research showing that eating meat has a negative impact on health also suffers from conflicts of interest. Now, those conflicts of interest come from many researchers compassion for animals - and there's a big moral difference between that and conflicts of interest which come from the greed of the meat industry. But from a scientific perspective, it's not legitimate to simply dismiss one side and accept the other.
Not everything has to be a both sides equivocation . Degree and severity matter. "Compassion for animals" and "receiving funding from a party with a vested interest in the outcome" are not equivalent conflicts of interest.
But from the scientific perspective, there is a specific factual question: what are the effects of meat consumption on human health? Nutrition research is super finicky. Even absent any conflict of interest, it's unclear that nutrition results are trustworthy. So I don't think it's fair to throw out every study which says meat is healthy and just focus on the studies that say meat is unhealthy.
Person A sees someone torturing a dog and kills them out of indignation.
Person B is a hitman-for-hire who doesn't know who he's killed or why.
Are person A and B really morally equivalent?
That's not what we're talking about, however. We're talking about what level of suspicion is appropriate in various scenarios. It's unlikely we can _know_ if results were purposefully sabotaged or not. We have to make some best guess. Interested parties funding studies is deeply suspicious, and should be treated with a hefty dose of skepticism. Hand waving that "maybe the researchers were motivated by empathy?!" is not at all equivalent. That is a incredibly low bar that, itself, undermines trust in science, as one could trivially make up similar excuses to distrust virtually any study ever conducted. Oh, researchers found declining sources of fresh water year over year? Biased. They probably just like cheap drinking water. Better ignore it. An Aquafina-backed study shows the opposite. That study is biased, too. But they're both equally morally reprehensible.
[1] https://www.statista.com/statistics/190362/total-us-wheat-pr... [2] https://www.statista.com/statistics/1167209/leading-global-c... [3] https://www.globenewswire.com/news-release/2023/05/12/266748.... [4] https://www.statista.com/outlook/cmo/food/fruits-nuts/fresh-...
[1] https://www.statista.com/outlook/cmo/food/vegetables/fresh-v...
I feel like it is beyond the "replication crisis" of any other science when your replication crisis involves potential war crimes. (p-hacking looks so quaint in comparison.)
If any other science had that sort of foundation and its replication problems that entire science would likely have been thrown out by now. A lot of people still think that there must be some sort of baby in all that extremely tainted bathwater and are afraid to throw it out.
(I have come to believe that nutrition science has become the last bastion of Phlogiston Theory in any of the sciences, and that is more damaging than people realize.)
Anyone who makes this statement and doesn't understand that this ratio depends on personal behavior is a flat out absolute idiot and shouldn't make any public facing statements. No way to sugar coat it.
This is regardless of whether nutritionists made any progress.
Nutrition is the smaller field about about what to eat, but it still can't say what to eat!
The optimal diet for someone who is completely sedentary is going to be completely different to the optimal diet for someone who gets a reasonable amount of exercise, and it's not going to be a flat multiplier.
The protein needs of an athlete are completely different. Simple carbohydrates are processed differently if eaten prior to heavy exercise. That's just the basic stuff.
The best advice I've read is to just eat and move like a mature adult.
That doesn't necessarily mean never having a sweet or a beer, but it does mean prioritising full real meals over stuff like donuts, cakes, 50g sugar "coffee" drinks etc.
Nutrition facts that have been known for 20+ years:
1. Increased calorie consumption causes weight gain.
2. Diabetics are unable to properly metabolize carbohydrates without insulin.
3. Fat is necessary to hormone production.
4. Protein is necessary to create or maintain muscle mass.
5. Carbohydrates with high glycemic index cause fluctuations in blood sugar and energy levels.
6. Fiber promotes bowel regularity.
7. People with Celiac diseases have an autoimmune response to gluten, a protein found in grains.
8. Iron is necessary to cognition, motor development, and energy levels.
9. Vitamin A promotes eyesight.
10. Calcium is necessary for bone strength.
11. Vitamin D promotes Calcium absorption.
Not a comprehensive list, just what I could think of off the top of my head.
Nutritional science is roughly concerned with the question, "what constitutes a healthy diet?", and it has failed to produce even partial answers at every turn.
Please cite your source.
Just one source of many: https://www.bmj.com/content/351/bmj.h3580 (2015)
> 2, 3, 4, 7, 8, 9, 10 and 11 come from cellular and molecular biology, not nutritional science.
These have all have nutritional studies.
For example, #7 dates back to the late 19th century, decades before molecular biology.
Another vastly replicated result you can find quite easily: low-glycemic-index diets and ketogenic diets can produce weight loss despite caloric excess.
And lastly, a reasoning from first principles reveals a prima facie credible flaw in the caloric balance hypothesis: the body is not a closed system, ergo the law of conservation of energy does not apply. More vulgarly: you can do things like "work up an appetite" or "shit excess food".
>These have all have nutritional studies.
The nutritional studies did not produce these initial findings. Without pointing to specific papers, it's hard to be very precise, but I would be willing to bet that these are either dietary studies building off of biological first principles, or replication-checks in broader studies. Both are totally fair practices, but can't be considered as an indication that nutritional science is a fruitful field.
If you run 20 more miles every day and eat 100 more calories, I suspect won't gain weight.
The banality of your arguments speaks for itself.
here's a counterpoint:
> Nutrition has made no progress. It has discovered no stable facts. Everything nutritionists have said, they have said the opposite ten or twenty years later (if not much sooner). They literally know nothing. After a century of countless experiments, the most common, most basic problem they’ve addressed—the optimal ratio of fat, protein, and carbohydrate—is completely unsolved. If they can’t figure that out, anything more sophisticated seems hopeless.
https://metarationality.com/nutrition