SearchResearch Challenge (9/20/23): What IS dietary fiber?

 I realized I don't know what "fiber" really is!  

I was at a farmer's market buying a few veggies for the week ahead, and while standing in line I was browsing my news feed, and came across an article about the amount of dietary fiber in different foods.  I was impressed to read that my favorite breakfast cereal, a "high fiber" food, delivered a "whopping" 3.57 grams of fiber in each serving.  

Years of SRS have taught me to be very wary of anything I read, especially when it's surrounded by such superlative adjectives. 

So I found myself wondering my SearchResearch type of questions:  "Is that a lot of fiber?"  And "so how much fiber should I be getting?"  

When I got home I did a little searching around and found that... I really don't understand what fiber is! 

In particular, I thought that fiber was the indigestible part of your food--you know, the little threads, husks, hulls, and tiny fragments that just pass straight through without much digestion seeming to take place. 

But when I let my cereal sit for too long in the milk, I know it turns into a pure paste.  There's nothing like the kernels of corn or bits of apple skin that (as far as I can tell) are untouched by my digestive juices.  How could there be any "fiber" in that glop?  

Later, I saw a bottled drink for sale in my grocery store that promised a solid 6 grams of fiber in a single drink.  So far as I could tell, the drink looked pretty much like some kind of exotic juice--not the pulpy slurry I would have expected.  

Can you help me understand what's going on here?  Today's Challenges are: 

1. So what, really, is dietary fiber?  Is it something more than indigestible bits like wheat bran, corn kernels, and rice husks?  

2. What is the current recommendation for dietary fiber in my diet?  Is 5 grams of fiber in a serving a lot?  Or is it a little?  

These don't look like difficult questions--BUT--when I did my research, I found the story much more interesting and complicated than I'd originally thought.  

Among other things, I've started looking at the listed amount of fiber in a food product with a huge grain of salt.  (Which will then upset my sodium intake, but so be it.)  

What IS the story with fiber?   It seems there's more here than meets the eye, the tooth, and the entire alimentary canal.  

Can you find out? 

Let us know what you discovered, and what you did to find out about it.  

Keep Searching!