Fiber Intake and Nutrient Absorption

[Salvatore]

Originally Posted by Primalkid

Where did you hear that fiber interferes with protein digestion?

He said absorption:

Originally Posted by mavajo

So given that high fiber interferes with protein absorption, does this become a relevant factor with Quest Protein bars? They typically have about ~17 g of fiber and ~20 g of Protein.

Originally Posted by lylemcd

I should mention that very high fiber intakes can increase the amount of nutrients being lost to excretion. For example, higher fiber intakes may reduce fat absorption by about 3 percent, protein by maybe 5%. It’s been estimated that increasing fiber intake from 18 to 36 g/day would increase caloric losses by about 100 cal/day or so.

Essentially, the fiber prevents the enzymes from being able to reach the nutrients, and they simply pass through unabsorbed. This is another reason that high-fiber intakes can be useful while dieting: decreased caloric absorption. Of course, no athlete or bodybuilder wants decreased protein absorption so its sort of a mixed blessing.

[Primalkid]

Originally Posted by Salvatore

He said absorption:

In rats? I would love to see Lyle's referenced study because I have never heard or seen literature to suggest it was true.