[trowawee]

Except most of those studies are bullshit bad science done with fundamentally flawed methodology. It got a throwaway line in the article, but just about the only honest way to make scientific conclusions about nutrition would be to take a human population of statistically significant size and diversity, move them underground to a controlled environment, and control and monitor their food intake for some period of years. That would be a data set that might not be spurious (although I bet even within that, people would find ways to eat stuff the researchers can't record). That's not going to happen, so nutrition will continue to mostly be junk science that utilizes crappy methods and statistical manipulations to create sensationalist headlines and keep selling books.

[spooningtamarin]

Well, I just said that there's a huge amount of quality work done in those 800 studies.

And what you suggested isn't at all uncommon in those quality work studies.

Checkout https://en.wikipedia.org/wiki/China%E2%80%93Cornell%E2%80%93...

A controlled environment of people not changing their diet and lifestyle in a 20 year time span.

There's plenty of studies like that.

There are quality studies where p-values tell that their sample size isn't large enough, but when you do a meta-analysis of studies with same methodology you get a relevantly sized sample.

I do guess you are talking about those "Phd nutrition guys" and yes, they are full of bullshit and aren't scientists, because if you are talking about the real science, your comment is full of disinformation.

[Grishnakh]

Not only that, but people's bodies differ greatly. People have different metabolisms, males use more energy than females, some people are bigger (taller) and heavier than others, etc. Also, people's bodies just work differently, some of which may be attributable to gut bacteria. Some people can get away with eating a lot more calories than others, or different foods, and have a totally different effect.

[woobar]

All these factors are accounted for. I.e. in a controlled environment individual metabolic rate, weight, gender, etc will be measured.

[HelloMcFly]

What wouldn't likely be measured with any sort of accuracy is individual variance is gut microbiota, which I'd assume could lead to notable differences. Even so, I think we'd get more signal than noise doing our best to measure and factor out what we are currently able to.

[biomcgary]

Sequencing to identify gut microbiota is now common in research. The general makeup of gut bacteria is relatively stable, so weekly or monthly sampling should be adequate.

[DrScump]

Microbiome, one of the most important factors, is not accounted for. Neither is genetics.