This is the things thar gets me the most. Code review is _hard_. So hard that I'm convinced my colleagues don't do it and just slap "LGTM" on everything.
We are trading "one writer, one reader" for "two readers", and it seems like a bad deal.
Not the poster, but, usually what people are referring to is all the other stuff that comes along.
Per calorie beef and broccoli are actually surprisingly similar, but broccoli comes with fiber, calcium and vitamin C, while beef comes with saturated fat.
Of course, broccoli is not very calorie dense, so you would need to eat a lot.
More realistically, tofu, which has about as much protein per calorie (and almost as much per gram) as middling lean beef. But has half the saturated fat, more iron, more calcium, and fibre.
You just get more good stuff, and less bad stuff with veg.
Bioavailabilty is a bit of a non-issue. It's measured as if the food you are measuring is the only food you eat. So if it is slightly low on one amino acid, the "bioavailabilty" drops, but noone eats like that. Once combined with other foods, the total "bioavailabilty" tends to increase.
Dietary cholestrol hasn't really been overturned, but sure there is some nuance. Some people do respond badly to dietary cholestrol (like you said, individual advice is sometimes required), but dietary cholestrol is also not a linear response afaiu. That is, if you eat one egg a day, you may as well eat 4, but if you can completely eliminate dietary cholestrol it could make a difference. So, many guidelines don't bother with suggesting it, because it's too hard to eleminate it to the point of mattering for the average person.
All that to say, the science isn't wrong, but the practicalities influence the advice.
The guidelines haven't changed, but they should be. The association between cholesterol and CVD is specifically related to blood cholesterol levels. However, in healthy individuals, blood cholesterol levels are not strongly impacted by dietary cholesterol choices - since cholesterol is synthesized in the body, there is homeostasis, and higher cholesterol intake leads to lower rate of synthesis, maintaining the same blood levels.
However, some individuals suffer from a bad regulation of this homeostasis, and for them dietary cholesterol does lead to persistent high levels of blood cholesterol as well. So the guidelines should apply for them, but not for everyone else.
That is quite an extreme take, and one that sounds like it was born from parroting social media takes. Ancel Keys was largely correct, and much of what he said is corroborated by modern science. Probably his main issue was that he was a bit too focused on saturated fat, which is not wrong, but not the only factor. He was wrong that sugar is just empty calories, though he never recommended replacing fat with sugar.
Modern science agrees that saturated fats lead to CVD, but replacing saturated fats with refined carbs also leads to CVD, which Ancel Keys didn't believe (though, to be fair, the populations he studied didn't have access to the types of refined carbohydrates we have today)
The dietary guidelines derived from his work did backfire, but Keys never said to replace saturated fats with refined carbs, which is what ended up happening. He advocated for substituting different fats. But the message that ended up being received was "no fat at all", which no scientist ever actually recommended AFAIU.
The diet he actually recommends is well studied, and found to be protective.
Fair enough! I was not aware of that. But she's far from the only one. There appears to be a wall of meta-analysis stating the same, but again, I'm naive and just googling.
Cochrane systematic reviews should make you seriously question whether the Mediterranean diet really is much good at all - hard data is inconclusive and low quality [1].
In general we really even barely have enough nutritional knowledge to say if the term 'good fats' even makes much scientific sense, but broad and vague things like "Mediterranean diet" are just total nonsense, from the standpoint of serious nutrition science.
That seems to be searching for RCT's, which, I'm not surprised would struggle to replicate. Most of these had a duration of less than 5 years, while dietary related health outcomes are the result of decades of following a pattern. It's possibly also unethical, in some cases (i.e. the existence of effective LDL lowering medication would likely complicate things).
Many people seem to disregard epidemiology, especially when it comes to nutrition (I think because it tends to support unpopular positions). But epidemiology has performed some excellent feats in the name of public health: cholera, smoking, pfao.
It is unfortunate that the large time-lines on these things make more rigor difficult, but I wouldn't throw out the epidemiology.
Epidemiology should generally be disregarded when it comes to nutrition.
There are exceptions when there are rare natural experiments (e.g. I forget the country, but the European one where some issue caused all flour for the country to be only whole-wheat, which led to clear nutrient deficiencies due to the phytic acid there) but in general there are way too many confounds, and measurement is far too poor and unreliable (self-report that is not just quantitatively but qualitatively wrong, and you can't track enough people nearly long enough), there is virtually no control whatsoever (diets and available foods shift considerably over just decades), and much of the things being measured lack even face/content validity in the first place (e.g. "fat" is not a valid taxon, and even "saturated vs. unsaturated" is a matter of degree).
We are missing so much of the basics of what are required for a real science here I think it is far more reasonable to view almost all long-term nutritional claims as pseudoscience, unless the effect is clear and massive (e.g. consumption of large amounts of alcohol, or extremely unique / restrictive diets that have strong effects), or so extremely general that it catches a sort of primary factor (too much calories is generally harmful, regardless of the source of those calories).
But even setting that aside, you can't define or study "Mediterranean diet" rigorously even in RCTs, so I don't see how you can think you are going to get much of anything here from epidemiological work that is going to lead to anything practically actionable.
Notably, the epidemiological study people like to dump on the most, largely did use natural experiments (i.e. they chose regions, that, at the time, had very traditional diets, without the convenience of supermarkets to mess it all up). They also didn't rely solely on food surveys, but actually measured the meals.
But all that aside, I don't actually follow a Mediterranean diet, and agree that one has to be careful here, because it is not well defined (or, it might be in some circles, but that differs from what the general population might expect).
The only reason I mentioned it was in response to
> The Mediterranean diet is regarded as quite healthy by many health professionals but, it is also high in carbs and fat.
Where I was pointing out that the fats in the Mediterranean diet (by pretty much every measure of what it means to be a Mediterranean diet), are not saturated, and it is usually saturated fats that are considered "bad".
That is, all I was trying to do was clear up the (common!) confusion about fats (they are not all the same).
Fair, the term may have been well-defined and measured in the original study, or in some specific circles. I was definitely thinking of the meaningless general thing "Mediterranean diet" has metastasized into today.
I also think it is better, rhetorically, to not draw support for the badness of saturated fats / differences of different fats by referencing the Mediterranean diet, since this rather looks like drawing upon narrow / weak science to support something that is in fact much more broadly supported by a larger variety of more careful work.
But yes, it is very important that people recognize there are huge differences here!
There are so many differences in lifestyle between the regions that they studied and other places that it is absurd to attribute the outcomes confidently to the diet. Especially when stress is a well known CVD risk in itself.
This sounds like they didn't think about it at all. Of course they did, and sure, their techniques were not as sophisticated as today. But there have been plenty of follow-up studies that have controlled more rigorously for those things, and it turns out they were probably right?
Also, the 7 countries study didn't just compare the regions, they also did intra-regional comparisons. Not that I think this particular study is what you should base all your evidence on, but, most others back it up.
The people who run these studies actually know what they are doing. They know the limitations of their methods, and, they have thought about confounding variables. This _always_ comes up in internet debate, like, "ahh, but there are confounding variables so the study must be trash!". It's literally their job to take those confounding variables into account. They don't just grab random people of the street to run these things. And I assure you, they know about the details.
I think git is overkill, and probably a database is as well.
I quite like the hackage index, which is an append-only tar file. Incremental updates are trivial using HTTP range requests making hosting it trivial as well.
This is the things thar gets me the most. Code review is _hard_. So hard that I'm convinced my colleagues don't do it and just slap "LGTM" on everything.
We are trading "one writer, one reader" for "two readers", and it seems like a bad deal.
reply