Being raised in the states, I've never had the opportunity to go to a real Korean bath house called jjimjilbang. But growing up my mom would give my sister and I a deep scrub bath once a week. She would basically use her thumbs or a special bath towel to scrub all our dead skin cells. When we were done, the bath looked so filthy! The dead skin cells are called Ddeh.
The Koreans believe that this scrubbing enables toxins to be eliminated. They also say that it makes your skin softer and that you have better circulation.