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Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
There are 20 feet of blood vessels in each square inch of human skin.
Approximately 500,000 babies are born each year in the United States to teenage mothers.
There are 60,000 miles of blood vessels in every adult human.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
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