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People about to have surgery must tell their health care providers about all supplements they take.
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
In 2012, nearly 24 milliion Americans, aged 12 and older, had abused an illicit drug, according to the National Institute on Drug Abuse (NIDA).
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
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