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Your heart beats over 36 million times a year.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
Blood is approximately twice as thick as water because of the cells and other components found in it.
The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
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