Nutrition Science is broken because of the financial incentives of companies to fund sham research to get their products sold.
I strongly recommend going to https://nutritionfacts.org/ for your information -- a nonprofit that never sells anything or promotes any products, just tries to distill research on nutrition in easy-to-understand videos and posts.
Nutritionfacts is ideologically driven operation. They only present one side of the argument. Plant based diet first, facts second. Being a nonprofit doesn't make you immune from bias. It's not just money perverting the field, but also ideology.
The whole field of nutrition is divided into camps, when they conduct meta-analyses of all the literature, they pick inclusion/exclusion criteria so that the side that they are championing wins.
Your comment is valuable, but at least Nutrionfacts seems to present one side of the argument factually.
There are operations like 'Brand Power'[1] which masquerades like consumer fact checking service but in fact they just 3rd party advertisers for brands.
When I first saw their Ads in India, I thought it's disingenuous and then I learnt that they do the same even in developed countries.
It's even more hypocritical than just cherry picking studies. Points in his books are refuted by the same studies he cites! He ignores similar / better outcomes that don't match his bias.
Misaligned incentives are certainly part of the problem, but this article points to it being more than just that - even if you want to run a good study, it is incredibly difficult to do so.
I have spent a bunch of time on that site and read Dr. Greger's book "How Not to Die". He certainly works hard to understand how studies could be flawed, but he is still limited by the fact that really good underlying studies are hard to come by.
A few things stood out to me reading that book:
1) So, so many studies are hopelessly flawed.
2) Even ones that seem relatively good often have other studies showing the opposite result.
3) The evidence for a plant-based diet seemed fairly overwhelming, but some of the specific recommendations felt more questionable.
4) If you combine all of the claimed increases/decreases in disease risk for a given set of foods, you can fairly quickly get to a ridiculous result where you have something like a 1 in a billion chance of getting a relatively common ailment or are almost guaranteed to get 3 different cancers tomorrow.
The non profit university researchers do just as bad, the whole field is one where good research is very very rare.
To be a little fair, we don't really understand much about nutrition or have easy ways to do high quality studies. A "gold standard" study is just the best of a bad lot. It's the rarest of humans that can say, "I spent 3 years of my life doing a study and didn't find anything significant".
This is definitely part of it, but I feel like it underplays the fundamental difficulty of studying nutrition.
Put yourself in the shoes of someone who wants to study this, and you rapidly see the problems. Effects of nutrition take many years to show, so you're generally going to need to track people for years. People move, get bored of talking to you, die, etc. Their diet also varies greatly over time. They don't always remember what they ate, and certainly can't quantify it with any degree of accuracy.
If you perform some intervention, it's hard to know that the people actually complied with it. You can do it in the short term by having an in-patient setting, but again you miss the long term effects, which are really what matters to most people.
I feel like people reach too easily for conspiracy theories these days…
It would be great if this website answered the question “what is a healthy diet”, instead of trying everywhere to get me to watch some of its hundreds of videos.
I feel like this attitude is part of why nutrition science is the way it is.
People are boxed into this "healthiness is a one-dimensional scale" thinking. Are eggs healthy or not healthy? Are potatoes healthy or not healthy? Is pizza healthy or not healthy?
But reality is way more complex and nutrition science knows very little about "healthiness" (to the extent that you can distill diet into a one-dimensional scale). Scientists only claim, "X is maybe correlated with Y (in Z population)".
So this simplification, plus the lack of definitive known truth, leads people to latch onto B.S. like "eating eggs is unhealthy because eggs have cholesterol".
I don't think it's an attitude problem that people expect nutritional advice to be actionable in some way. Because at the end of the day the only decisions I'm able to make is choosing to eat or not eat something. If you can't write down a set of rules for me to follow that eventually halts and resolves to a "yes" or "no" then there's no point.
I don’t think it’s unreasonable to expect that there be a landing page that says “most healthy people should follow a Mediterranean diet” or similar.
Sure, there are food allergies - I have some myself - but this site seems like it’s trying to get me to buy the book and give the video views. I want information in text quickly. Then if I want to learn more, more information in longer text. This is how almost all valuable information is conveyed across all topic areas.
Isn't that literally impossible, because there are so many different things that a subset of people need to avoid eating? e.g., if you have a nut allergy, your healthy diet can't include nuts; if you're lactose-intolerant your healthy diet shouldn't include lactose; if you have coeliac disease, your healthy diet can't include gluten; if you have IBS your healthy diet shouldn't include anything that triggers it (which is different per person); if you have diabetes (type 1 or 2) your healthy diet can't include sugar; etc., etc. And god forbid you have 2 or more dietary issues...
Plus different activity levels make different diets healthy - if you're a professional athlete needing 6,000+ calories per day, "healthy" for you is very different to healthy for me, who sits at their desk all day.
This isn't even accounting for personal preferences like being vegan, or religious restrictions.
I think you're misunderstanding the claim. It's name a healthy diet. A single one. A diet which followed to the letter for the time span its prescribed will not cause any health problems traceable back to it. Make whatever assumptions about the hypothetical person you need and assume that they follow the diet for only as long as those assumptions hold.
There is no "healthy diet" that is universally applicable. Go back and look at the list of different possible restrictions in the parent post.
Then add the fact that many people are allergic to all kinds of different things.
Then add to that the fact that people of different ethnic backgrounds are adapted to do better with different balances of nutrients.
Any "hypothetical person" such as you describe would, fundamentally and inevitably, "normalize" one specific type of person and "other" everyone else. Claiming that "this is a healthy diet" in such a way would be grossly irresponsible, even if you then went on to list the features of a person it is "healthy" for.
Finally, even if you wanted to make such a description, the whole point of this thread is that we do not have a scientifically-rigorous-enough idea of what it would be to be able to do so with a high degree of certainty, even for a clearly-defined set of parameters for who would be eating it.
I didn’t ask for it to be universally applicable, or even broadly applicable. Or even applicable to more than the person the question imagines. I asked if we have enough information to know one single example of a healthy diet for one imaginary person who you are allowed to assume has no complicating factors.
Because if we can’t answer this much much simpler problem then we have no hope of giving nutritional advice to a population that is as varied as you describe.
I don't want to go through a bunch of training to learn how to write good software. It would be great if a website just told me which buttons to press on the keyboard.
I strongly recommend going to https://nutritionfacts.org/ for your information -- a nonprofit that never sells anything or promotes any products, just tries to distill research on nutrition in easy-to-understand videos and posts.
Here's an example: "How the Egg Board Designs Misleading Studies" https://www.youtube.com/watch?v=2s25RaOZsFM