"Cleansing is ridiculous. You know what's been around longer than that state-of-the-art juicer? Your kidneys. And your liver," says author Sloane Crosley. Livers have been around since mammals have existed. But for all their hard work, most of us couldn't name 3 of the liver's tasks. And we're not to blame. The liver does a LOT. Main chores are to detoxify, digest, and store nutrients. Thanks, liver! If the liver gets sluggish or diseased, though, things start to back up. The first sign is yellow skin or eye whites. Why, you ask? Bilirubin, a yellow molecule, comes from the breakdown of red blood cells and normally gets added to bile. When the liver slows down, bilirubin backs up in the blood and things start to look yellow - ie, jaundice. It's normal for newborns to have jaundice for a few days after birth. In the womb, the placenta filtered the bilirubin for the baby. Over time the liver catches up on its tasks and everything goes back to normal.