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The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Green tea is able to stop the scent of garlic or onion from causing bad breath.
There are 20 feet of blood vessels in each square inch of human skin.
The people with the highest levels of LDL are Mexican American males and non-Hispanic black females.
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