An American study has found that vitamin D deficiency is significantly associated with bilateral hearing loss at low frequencies (low-frequency hearing loss). The study found no association between vitamin D deficiency and hearing loss at high frequencies (high-frequency hearing loss).
The purpose of the study was to examine whether vitamin D deficiency and hearing impairment, specifically sensorineural hearing loss, are associated.
The study used data from the National Health and Nutrition Examination Surveys in the US. 3,489 people aged 50 years or older participated in the study. 924 of the participants (21.8%) had vitamin D deficiency. Hearing loss (bilateral hearing loss and unilateral hearing loss) was detected among 1,648 (40.5%) participants at low-frequency and among 2,589 (70.5%) participants at high-frequency.
The pure-tone average (PTA) was calculated for each ear at low speech frequencies of 0.5 to 4.0 kHz (LPTA) and higher frequencies of 3.0 to 8.0 kHz (HPTA). Hearing loss was defined as a hearing level of more than 25 dB.
Vitamin D important for our hearing
In the study, the researchers concluded that vitamin D may have a significant role in the human auditory system, where its deficiency might affect both ears and in particular the inner ears where the sensorineural hearing loss occurs.
The study, "Deficiency in vitamin D is associated with bilateral hearing impairment and bilateral sensorineural hearing loss in older adults", was published in the journal Nutrition Research.