A single hair grows about 0.3 to 0.4 mm a day, roughly a centimeter a month. But your scalp has around 100,000 of them. Laid end to end, their daily growth adds up to more than 30 meters, the height of a ten-story building. Every day, your body spins out tens of meters of fiber.
Every day, your kidneys filter around 180 liters of blood plasma, about a bathtub's worth. Yet you only have about 3 liters of plasma, so it passes through your kidneys some sixty times a day. Over 99% of the filtered water is reabsorbed, leaving just one to two liters of urine.
A 70 kg adult is made of about 7 × 10²⁷ atoms, or seven billion billion billion. The observable universe is thought to hold on the order of 10²² to 10²⁴ stars. Even with the high estimate, you contain thousands of times more atoms than there are stars in the entire visible cosmos.