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About 600,000 particles of skin are shed every hour by each human. If you live to age 70 years, you have shed 105 pounds of dead skin.
Vaccines prevent between 2.5 and 4 million deaths every year.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
There are 60,000 miles of blood vessels in every adult human.
Approximately 70% of expectant mothers report experiencing some symptoms of morning sickness during the first trimester of pregnancy.
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