Yes. The simple fact is that nutrition epidemiology has failed. We don't know much of anything, other than a handful of basics like avoiding loads of refined sugar and trans fats.
That's not completely true, the information is just harder to find and more complex to make popular.
For example, bad fats still play an important role in clogged arteries, but it's more nuanced then that. There are many kinds of fat, and there are other variables in causing fats to clog arteries, such as sugar.
Well, so yes, it does seem that avoiding refined sugar and trans fat and not overdosing on calories, and keeping highly active in terms of exercise, and not being in the same position for too long, and avoiding foods that inflame you (which seems to be very personal), and making sure you get a varied diet of nutrients, is all we know.
I just don't know if that should be framed as a failure. Could just be that it's a hard problem, could be that there are no real pattern to learn about as well. The latter is interesting, because we start our nutrition quest believing nutrition can affect health to a great deal, but that could just as well be false, nutrition could be a very small factor on health.
I think the problem is just the tendency we all have for snake oil, shortcuts and easy way outs. That is where I think this impression of "failing" comes from. That we didn't find something easy to do and that works very well. In that sense, science is characterized by lots of failures.
* saturated fats are bad (lies told us by a crappy Ancel Keys study, promoted for decades by processed food companies (like Kellogs) ran by Seventh Day Adventists who were convinced "meat led man to dangerous impulses and temptation")
* polyunsaturated fats are good. The American Heart Assocation had an article up for years that went as far as to claim Omega6s are heart healthy. They only recently took it down this year. But we know they're inflammatory and we know we're consuming 25-100x more Omega6s than we ever would before the industrial invention of seed-oils being shoved into every product imaginable (bread, cereal, granola, anything that comes in a box, feed given to animals meant for meat production) here's a webmd article on it: https://www.webmd.com/heart/news/20090126/expert-panel-omega...
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* sunlight creates high cancer risk (ignoring that cancer is unlikely, treatment if caught early has a high survival rate, and the risk of not having vitamin d throughout your life risks far more likely autoimmune issues, depression, anxiety and even certain cancers and inflammatory disease).
* sugar is good for you. Sure, they'll specify processed sugars are bad for you or "added sugar", but common wisdom will accept a NET (subtract fiber) 200-300g carb diet as acceptable. Grain is still often listed as the most important and largest part of the food pyramid.
The reality is - all mainstream health advice, including that which you'll get from your doctor who got a whole single nutrition class in school, ensures that processed foods don't loose business on the front end and the medical/pharma industries don't lose money on the back end.
even in the push for a more vegetarian/blue-zone diet world - they're doing so by promoting meat alternatives like "Beyond Meat" which is chock full of so much seed oil and other processed substances, it's mainstreaming vegetarianism-as-fast-food. McDonald's burger.. is still a McDonald's burger and you shouldn't be eating it.
If a factory isn't making it at scale, shoving it in a box, branding it and ensuring you don't have to spend any time making/cooking/preparing whole, fresh foods (those pesky things that tend to have short shelf lives and are costly to Ag businesses), then your PCP, the government, most food businesses, your medical insurance company, absolutely no one of any kind of "authority" isn't going to promote it highly.
They'll do ANYTHING except remove seed oils. They'll make your potato chips out of broccoli and carrots and still drench them in sunflower or canola oil. They'll reduce the salt. they'll make shit out of beets. And still manage to make it horrible for you.
The MSM regurgitates "health" info regarding diets in a way that acts as advertising for these orgs.
what's an acceptable oil? olive? peanut? I was told to use olive oil (not even EVOO except for taste related) so that's what I get but it's impossible to know anything.
Anything thats mono or saturated fat. Mono is probably healthier. But coconut oil, beef tallow, duck fat, butter are all healthier than canola, sunflower, or soybean oil or crisco.