Melanin may affect hearing
Some scientists believe black people's larger amounts of melanin protect them from noise-induced hearing loss as the years go by, study researcher William Murphy said. Scientists suspect melanin plays a role in how the body removes harmful chemical compounds caused by damage to the sensitive hair cells in the inner ear.
Genetics or the amount of noise exposure may explain the difference between women and men, said Elliott Berger, an Indianapolis-based hearing protection expert.
The conclusion that the nation's overall hearing has not changed since the early 1970s seems to contradict other recent research finding that modern teenagers do not hear as well as children did in the age before mobile listening devices, Berger said.
The study, reported at a scientific conference last week, looked at more than 5,000 people who had hearing tests from 1999 through 2004 as part of an annual federal health survey.
On average, the 1,077 non-Hispanic blacks in the study could hear higher tones at 15 to 22 decibels, while the 2,518 non-Hispanic whites could hear high-end tones at 21 to 32 decibels, on average, the study found.
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Melanin Helps Blacks Hear Better Than Whites