Our Skin

If you're wondering exactly how many skin cells fall off, get ready for some staggering numbers. Scientists estimate that the human body is made up of around 10 trillion cells in total. Your skin makes up about 16 percent of your body weight, which means you have roughly 1.6 trillion skin cells [source: BBC]. Of course, this estimate can vary tremendously according to a person's size. The important thing is that you have a lot of skin cells. Of those billions of skin cells, between 30,000 and 40,000 of them fall off every hour. Over a 24-hour period, you lose almost a million skin cells [source: Boston Globe].
Where do they all go? The dust that collects on your tables, TV, windowsills and on those picture frames that are so hard to get clean is made mostly from dead human skin cells. In other words, your house is filled with former bits of yourself. In one year, you'll shed more than 8 pounds (3.6 kilograms) of dead skin. It gets even grosser: Your house is also filled with trillions of microscopic life forms called dust mites that eat your old dead skin.