Hearing declines with age for many reasons. To see how nutrition might affect hearing, doctors in one study eliminated those who might have lost hearing due to infection, disease, trauma, noise or ear-damaging drugs.
Researchers tested 126 apparently healthy men and women, aged at least 60, and found that those with hearing loss in high frequencies—the type most common with age—or speech frequencies, had blood folate levels about one-third lower than those with normal hearing. People with more vitamin B12 also tended to have better hearing than those with lower B12 levels.