We’ve mostly studied gut health. Something about modern diets is messing that up substantially. Some think it may be Roundup, others dish detergent, others some microbe we can’t culture on Petri dishes.

What's the evidence that modern diets are substantially messing up gut health? (just curious, not (necessarily;) sceptical)

there is a sort of concept that states "you are your biome", and no end of evidence to show that poor gut and other flora causes disease, with many ways to get there, diet bieng one there are many tribal groups that fair exceptionaly poorly on modern wester diets, with well documented cases of plains indians haveing spontainious remission of diabetes when going to the much leaner diet of there ancestors. this ties in with another sort of concept that there are no true racial or tribal differences, but there are enzymatic adaptations in population groups that are tied to environments and food sources that tend to get inherited, the upshot for many modern people is that it's a semi random crap shoot, as there are prople who go ahead and outlive all of there peers, and do whatever they feel like, smoking ,drinking, junk food eating octogenarians, not many, but some

The incidence of crohn’s, IBD, celiac, etc going on out there. Some people want to throw obesity into that ring as well. Inflammation certainly causes weight gain.

Ah ok, well, obesity incidence is probably almost entirely explained by the amount of sugar and fats in modern diets. I wouldn't have thought of it as pertaining to gut health specifically, but no doubt there can be relationships there.

The other things seem more plausible. Purely anecdotally, my step-dad always thought he was intolerant to gluten because of his reactions to British bread, but when he spent a lot of time in France and tried bread there, he was fine.

Could be there's something about the production process of the standard British "Chorleywood loaf" that aggravates some bowels.

https://en.wikipedia.org/wiki/Chorleywood_bread_process

In general, I find it quite easy to believe that a lot of mass-produced foods contain what are essentially poisons, but I'm curious about evidential links (and I'm also aware that lots of naturally-occurring foods can be poisons if eaten too much, but that's a different question)

> Ah ok, well, obesity incidence is probably almost entirely explained by the amount of sugar and fats in modern diets.

The obesity epidemic started rapidly around 1980, but it's unlikely diet changed for the worse since then.

Also, it happened to lab animals and pets as well.

https://royalsocietypublishing.org/doi/abs/10.1098/rspb.2010...

Also, it appears to be correlated with low altitudes and interventions that cause you to move to higher altitudes cause weight loss.

https://journals.plos.org/plosone/article?id=10.1371/journal...

> Purely anecdotally, my step-dad always thought he was intolerant to gluten because of his reactions to British bread, but when he spent a lot of time in France and tried bread there, he was fine.

The American equivalent of this (people who go to Europe and think the bread is healthier because it's easy to digest) is because we fortify wheat and the extra nutrients esp. iron cause stomach discomfort.

You need to define "spent some time". Was he working? On sabbatical or holiday?

"I travelled somewhere and things improved" has the serious complication that you changed almost everything at once and possibly removed major stress sources. You were even outside of your own home - and buildings have ecosystems themselves anyway as well as just systemic faults.

Yeah ok, but it's just an anecdote so it doesn't count as generalisable evidence in any case.

I would just add that when he got back to Britain and tried baguette style bread there he found that he could tolerate it in Britain too.

Again, I'm just reporting a story as it was told to me because I was reminded of it in response to the previous comment.

I believe that ultraprocessed foods are recognized as borderline poisons. Esp if they contain trans fats or hydrogenated fats, which arw described as "slow acting poisons" - but the same goes for "extruded foods" - stuff that is processed to the point where it can be molded or squeezed into funny looking shapes.

Why assume it's the diets rather than antibiotics? Your gut microbiome develops during the first ~3y of life(including partial heritability from your mother), after which the total set of microbes in it remains approximately constant throughout your life, with only the relative proportions of them shifting with diet changes.

In contrast, antibiotics often kill a strain of a few off completely, while suppressing everything else except for a few strains that resist the antibiotic, which also creates a massive opportunity for new bacteria to colonize. And these deficits are partially heritable.

I find the dish detergent hypothesis more compelling than I used to - before moving to Australia. Here, I've noticed that almost nobody rinses the dishes after washing them (something I have always done). Curious what others do in different locations/cultures. Seems pretty obvious that consuming surfactants, triclosan, phthalates, alkaline agents, synthetic fragrances and dyes is not a great gut health strategy.

Doesn't that make the next serving of food taste like soap?

Not food but we definitely grew up in Australia with drinks that tasted a little of detergent from a generation of families that never had a dishwasher.

Far less common now as dishwashers became cheaper and more ubiquitous.

Worthy noting not rinsing in Australia is almost certainly a regional | family habit.

Sixty plus years here and four generations of our family and most people we know rinse off plates and glasses and vigorously dry with a fresh towel.

Koreans live off of fermented kimchi, something like 80+ pounds per person every year. Do Koreans have lower incidence of gut complications?

They have a much higher stomach cancer rate.

They also drink like fish and eat hot foods. Both of those are known contributors.

I bet they've got lower rates of hep than America, but that probably doesn't have anything to do with the kimchi.