How much food is absorbed, and how much comes out again?

915 views

I always thought that most of the food comes out again after nutrients are absorbed.

For example, here is a can of noodles. It says the 800gr in the can have a total of something like 600kcal. If the entire can would be converted into fat, this would have to be about 5500 kcal. That would mean that about 90% of it comes out again.

But sometimes I eat and eat and eat and a lot less is coming out then went in.

So, how much food is actually coming out again after being processed in the body?

In: 128

24 Answers

Anonymous 0 Comments

Most of what comes out is not the food that goes in. Most of the fiber comes back out, but the rest is bacterial growth, dead intestinal cells, and excreted gunk pushed out from your liver in the bile and not resorbed. (Bilirubin related compounds are in the last category and give feces it’s distinctive brown color).

Digestion is a ton more effective with a dozen bacterial species assisting in the breakdown, each doing things you genetically can’t. When those bacteria die they’re excreted. They grow best when there’s good fiber- insoluble for them to grow on and soluble they can partially digest. What’s left of the fiber comes out with them.

You are viewing 1 out of 24 answers, click here to view all answers.