Top 10 Medical Mysteries We Tried to Solve in 2008

Don't sweat it, shorty
Don't sweat it, shorty
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If some medical mysteries are more pressing than others, then one's proximity to death should be at the top of the list.

According to Randy Newman, short people got no reason to live. Mr. Newman may want to consider rewriting his lyrics, because some scientists posit that those very same short people will outlive the rest of us.

Japanese women live longer than anyone else, with an average lifespan of 86 years -- and they're only about 58.87 inches (149.54 centimeters) tall when they're in their late 70's. Why would tiny people live the longest?

In some cases, it might have something to do with the Methuselah gene. This genetic mutation, named for a Biblical personage who reportedly lived to be 969, decreases an organism's use of insulin-like growth factor 1, a growth hormone. Animals and humans with this mutation tend to both live longer and be smaller.

But what about people who don't have the Methuselah gene? For your average guy or gal, is height an important predictor of lifespan?

­If you more closely resemble the Jolly Green Giant in stature than the Keebler elves, take heart: Factors from income level to birth weight can influence the length of a person's life.

Find out more in Do short people live longer?