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Hippocrates noted that blood separates into four differently colored liquids when removed from the body and examined: a pure red liquid mixed with white liquid material with a yellow-colored froth at the top and a black substance that settles underneath; he named these the four humors (for blood, phlegm, yellow bile, and black bile).
There are 20 feet of blood vessels in each square inch of human skin.
Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Many supplement containers do not even contain what their labels say. There are many documented reports of products containing much less, or more, that what is listed on their labels. They may also contain undisclosed prescription drugs and even contaminants.
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