My money is on massive overexposure to high fructose corn syrup in the Western diet.
US diet? Is corn syrup common elsewhere?
It's also the crazy amounts: we're accustomed to high levels of sweetness. Like 40g sugar in a can of soda.
Why would more fiber help?
> Why would more fiber help?
Because there is an incredible amount of research into high fiber diets being good for your gut, including reduced colon cancer rates. This is the consensus of various organizations such as WHO - high fiber diets have lower risks of colon cancer.
Western diet collapsed its fiber intake well over 80 years ago - it would have shown up already.
Well, you said "can't" and I asked "why", which feels very reasonable to me. Your argument seems to be that it wouldn't account properly for the data - specifically, you're saying we would have seen colon cancer rates rise earlier.
> Western diet collapsed its fiber intake well over 80 years ago - it would have shown up already.
I don't really buy this for a lot of reasons. Probably the two most important are (a) ability to screen historically and (b) the timing isn't particularly "off" for the fiber argument. We did see it already, we've been seeing increases in color cancer risks for decades.
Now, I'm not married to it "just" being fiber whatsoever, but if I were to "bet" on the major contributing factor, naively, that's where my money would go. I think it's very reasonable to not place your bet there.
I would also bet top reason is fiber but it isn't the only reason - multiple factors at play.
Very high.
> But if a person is regular and does not have any gut issues, how would more fiber help?
There is a ton of research about this and it's why WHO and other orgs state explicitly that fiber reduces rates of colon cancer.
Fiber does nothing.
1. Ancient egyptians ate fucktons of wheat and barley, lentils, chickpeas, etc. They ate massive amounts of fiber lol I mean holy fuck I just can't believe how wrong you are?
2. Fiber is very, very well understood by ALL health organizations to be preventative for colon cancer.
Homo genus is 2 million years old.
Repeating "muh authorities" isnt an argument.
Your willful axiomatic dogmatism isnt science.
Cave paintings dont depict agriculture. They depicted hunting and agrarian nomadic lifestyles
Insoluble fiber speeds up gut motility. Faster gut motility means less time for toxins to sit and absorb in your gut.
Also, fermentable fibers serve as substrate for gut microbes, producing short-chain fatty acids (butyrate is one - a primary fuel source for colonocytes - the cells that line your colon).
It also lowers colonic pH, inhibiting pathogenic bacteria.
Lastly, (although there are tons more benefits I'm not listing), soluble fiber is incredible for people trying to lose weight, as highly fibrous foods increase satiety, keeping you fuller for longer.
And it's also well-documented that the average Western diet is highly deficient in fiber and that this is a thing which has gotten much worse in the last 75 years.
There also seems to be at least some light evidence that there may be generational effects - that the starting point of your gut is already bad if your mother's was.
Like where would the need for the fiber come from evolutionary.
All those were very high in fiber. I believe it's estimated paleolithic humans are over 100 grams of fiber a day, whereas I believe the recommended intake today is 35 grams, which less than 2% of Americans meet.
So yes, the Paleo diet is largely bullshit. No, humans did not eat fatty farmed meats. They barely ate meat at all.