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Aspirin is the most widely used drug in the world. It has even been recognized as such by the Guinness Book of World Records.

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Not getting enough sleep can greatly weaken the immune system. Lack of sleep makes you more likely to catch a cold, or more difficult to fight off an infection.

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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.

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About one in five American adults and teenagers have had a genital herpes infection—and most of them don't know it. People with genital herpes have at least twice the risk of becoming infected with HIV if exposed to it than those people who do not have genital herpes.

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Essential fatty acids have been shown to be effective against ulcers, asthma, dental cavities, and skin disorders such as acne.

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