“Preventing Hearing Loss with Nutraceuticals”
By Kathleen C.M. Campbell, PHD
Excerpts published in CAOHC's "Update", Winter - 2012 edition.
Council for Accreditation in Occupational Hearing Conservation
Dr. Campbell performed studies for two decades in her laboratory testing oral antioxidant nutraceuticals as protective agents to prevent hearing loss.
Three primary agents were experimented with. They were: D-methionine; Ebselen a mimetic for Glutathione Peroxidase; Vitamins A, C, E, in conjunction with Magnesium.
She had most experience with D-methionine. The conclusion was when following the treatment regimen of 2 doses daily for two days prior, the day of and for two days after the encounter of 105 decibels SPL KHz octave band noise exposure prevented permanent noise induced hearing loss and cochlear outer hair cell los in chinchillas. It was also effective when administered one hour following 105 dbs SDPL4 KHz octave band noise exposure after inducing a temporary threshold shift and still rescued from a permanent noise induced hearing loss. [Campbell et al 2007]
In a more recent study, D-methionine was administered 3, 5 and even seven hours after the same level of noise exposure cessation prevented noise induced threshold shifts and cochlear outer hair cell loss. [Campbell et al 2011]
Clifford et al 2011 reported that even relatively low levels of D-methionine can provide significant but partial protection against noise induced hearing loss.
Sampson et al 2008 found that D-methionine prevented noise induced hearing loss even if only given one hour before and one hour after noise exposure.
Introduction of nutraceuticals in the treatment of anticipated and unanticipated noise exposures could be very useful for the military, firefighters, policemen, recreational activities, emergency medical and various other occupation personnel.