Literal "Pound of Flesh" - best choices?

[The Controvert]

Warning: this thread may cause loss of appetite.

Ok, suppose you are a healthy adult and had to literally give up a pound of flesh. What stays and what goes?

Let's define flesh as tissue with the following caveats:

Hair, bone, teeth, and fluids such as blood, spit, etc. don't count. No toenails, too.
Adipose tissue (fat tissue) is too easy... so it's out.
You're healthy, so no tumors or gangrenous tissue.

Here's my thoughts: it breaks down into three categories.

1. Things you'd permanently regret losing (like brain, heart, hands, genitalia, etc.)
2. Things you'd temporarily regret losing (like skin that grows back, or you got a duplicate like kidney / lung)
3. Things you won't miss or would gladly lose (appendix, tonsils, uvula, sinuses)

Do the things in category 3 add up to a pound?