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Your skin wrinkles if you stay in the bathtub a long time because the outermost layer of skin (which consists of dead keratin) swells when it absorbs water. It is tightly attached to the skin below it, so it compensates for the increased area by wrinkling. This happens to the hands and feet because they have the thickest layer of dead keratin cells.
Everyone has one nostril that is larger than the other.
All adults should have their cholesterol levels checked once every 5 years. During 2009–2010, 69.4% of Americans age 20 and older reported having their cholesterol checked within the last five years.
Most fungi that pathogenically affect humans live in soil. If a person is not healthy, has an open wound, or is immunocompromised, a fungal infection can be very aggressive.
Asthma cases in Americans are about 75% higher today than they were in 1980.
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