Previous research suggests that harmful free radicals are produced in the inner ear in response to noise exposure. This free radical formation decreases blood flow in the inner ear and contributes to noise-induced hearing loss. Antioxidants neutralize free radicals and protect against oxidative stress (cell damage caused by free radicals). Now research reports that a combination of antioxidant vitamins A, C and E plus magnesium can prevent noise-induced hearing loss.
The study, published in Free Radical Biology and Medicine, investigated whether antioxidant vitamins and magnesium supplementation can prevent hearing loss. Researchers at the University of Michigan administered a diet supplemented with either vitamins A, C and E; magnesium alone; A, C and E plus magnesium; or a placebo to guinea pigs, one hour before and 5 days after noise exposure. The guinea pigs were exposed to 120 decibel sound pressure level noise for five hours.
The researchers found that the combination of vitamins A, C and E plus magnesium effectively reduced hearing loss and damage to the inner ear cells. The nutrients decreased free radical damage before and after noise exposure. However, treatment with vitamins A, C and E or magnesium alone did not effectively reduce hearing loss or cell damage.
"This study supports roles for both free radical formation and noise-induced vasoconstriction in the onset and progression of noise-induced hearing loss," the study authors write. "Identification of this safe and effective antioxidant intervention that attenuates noise-induced hearing loss provides a compelling rationale for human trials in which free radical scavengers are used to eliminate this single major cause of acquired hearing loss."
REFERENCES:
1. Le Prell CG et al. Free radical scavengers vitamins A, C, and E plus magnesium reduce noise trauma. Free Radic Biol Med 2007 May 1;42(9):1454-63. Epub 2007 Feb 20.
Posted by Elaine Gavalas on March 31, 2007 12:15 PM
