Researchers this week revealed the results of some demographics studies of noise-induced hearing loss (NIHL), something they say had yet to be studied to this extent. If you're a married white male driving a convertible, listen up while you still can.
The studies were presented at the American Academy of Otolaryngology-Head and Neck Surgery Foundation's 2009 annual meeting in San Diego this week. One study, which analyzed the audiometric testing data from 5,290 people ages 20 to 69, finds that more than 13 percent suffer from some level of NIHL, which means some 24 million Americans might as well. The strongest association they found is gender, with men being 2.5 times as likely as women to develop NIHL. Among men, those who are married (too much nagging?) and white (they specify "non-Hispanic") are at the highest risk.
Another study looked at drivers who ride in convertibles with the top down on a regular basis. Researchers say that long or repeated exposure to noise above 85 decibels can result in permanent hearing loss; in the convertibles they studied going 50, 60, and 70 miles per hour, drivers were consistently exposed to sounds between 88 and 90 decibels--due to noise associated with road surfaces, traffic congestion, wind, etc.
As a frame of reference, the American Speech-Language-Hearing Association says that "faint" sounds (library, whispering) are 30 decibels; "moderate" sounds (quiet room, rainfall) are 40 to 50; "very loud" sounds (vacuum cleaner, busy traffic) are 60 to 80; "extremely loud" sounds (chain saw, drum rolls) are 90 to 110; and "painful" sounds (jet plan takeoff, rock music peak) are 120 to 150. Riding in a convertible, then, results in exposure to "very" and "extremely" loud sounds. (The association did not rate the decibel level of nagging, though "conversation" clocks in at 60 decibels, so extrapolate from there as you will.)
Yet another study, which identified 3,559 men with hearing loss, found that while increased intakes of antioxidant vitamins such as C, E, and beta carotene have no effect on one's risk of hearing loss, men over the age of 60 who consumed high amounts of folates (found in spinach, asparagus, beans, peas, and liver) had about a 20 percent decrease in risk of developing hearing loss.
The authors say this is the largest study to delve prospectively into the relationship between diet and hearing loss. They relied on data from the Health Professionals Follow-up Study cohort, active between 1986 to 2004 and involving more than 50,000 male health professionals who filled out detailed health and diet questionnaires every other year.
Of course, male and female motorcycle drivers of any ethnicity, relationship status, and dietary tendency are probably at greater risk of hearing loss than those who do not ride motorcycles. In the meantime, if you start seeing white men with wedding rings munching on greens in their convertibles, you'll know why.