Asked by: Paul Leslie, by email
According to a 2011 study published in the journal Environmental Science & Technology, we shed between 0.03 and 0.09g of skin every hour. That sounds like almost nothing, but over the course of a lifetime it adds up to about 35kg, or roughly half your bodyweight. Most of this is in the form of tiny flakes, which make up a major constituent of house dust.
Interestingly, the same study found that the squalene oil on shed skin reacts with harmful ozone in houses, offices and aeroplanes, so dust can actually improve the air quality.
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