The recommended daily fiber intake is 25g for women and 38g for men in the USA, and 95% of us don't meet this amount. This suggests an urgent need for us to increase our daily fiber intake, which can be achieved by swapping out ultra-processed foods and animal foods that are void of fiber with whole plant foods such as fruits, vegetables, legumes, whole grains, nuts, and seeds.
I once had a consultation with a surgeon about hemorrhoid surgery. Her recommendation was to use fiber supplements because it's almost impossible to get enough fiber from food alone.
(I ended up getting a bidet, and now my fiber-poor garbage diet doesn't cause that particular problem anymore )
polished grains are a terrible curse upon humanity, just switching them out for whole grain is such an easy boost to your health. Not just more fibre, but more vitamins and stuff too along with proportionally less simple carbs!
I had to start supplementing with psyllium fiber (powder) several months ago after a massive hemorrhoid attack last fall. (Surgeon gave me the identical advice.)
If I don't get at least 40 g a day of total fiber (about 20+ of which are the powder), stools get large 'n' hard. It's working, and my ass is thanking me.
What I'm having trouble squaring is I don't think we evolved eating that much fiber every day. Pre-agriculture it would have been (depending on which part of the planet) lot's of animal protein and whatever roots & berries you could find, right?
Micheal Greger in "how not to die" talks about this. He says that hunter gatherers would eat mostly plants and sometimes some meat. And all plant food was not process so with lot of fiber