These relate to urinary sediments in the kidneys, and possibly the urinary bladder. The sediments can conists of uric acid crystals, or crystals made of oxalic acids, amono acids, or phsophate acids. Kidney cleansing can disssolve them and reduce the incidence of the tiny pimples under the eyes.
There is no real advantage in worrying. Worry has a slowing or paralysing effect on the cells of the inner organs by reducing blood flow through the viscera (internal organs) to increase blood vlume in the back of the brain and muscle area (for the flight or flight response). So if you don't have anything to worry about, this saves you a lot of sufferiong and hardship. Keep it that way.