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There are more sensory neurons in the tongue than in any other part of the body.
More than 150,000 Americans killed by cardiovascular disease are younger than the age of 65 years.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.
Vaccines prevent between 2.5 and 4 million deaths every year.
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