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In 2012, nearly 24 milliion Americans, aged 12 and older, had abused an illicit drug, according to the National Institute on Drug Abuse (NIDA).
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Aspirin is the most widely used drug in the world. It has even been recognized as such by the Guinness Book of World Records.
Thyroid conditions may make getting pregnant impossible.
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