A higher intake of omega-3s may protect against age-related hearing loss

A recent study links higher levels of omega-3 fats acid DHA with a reduced likelihood of reporting age-related hearing impairment, reinforcing the growing evidence for the role of omega-3s in maintaining health and preventing age-related disorders.

Researchers report that blood levels of the omega-3 fatty acid docosahexaenoic acid (DHA) were inversely correlated with hearing impairment in a new population-based cross-sectional study. Middle-aged and older adults with higher DHA levels were 8-20% less likely to report age-related hearing problems than those with lower DHA levels.

Higher levels of DHA have previously been associated with a lower risk of heart disease, cognitive impairment and death. Our study extends these findings to suggest a role for DHA in maintaining hearing function and helping reduce the risk of age-related hearing loss, said Michael I. McBurney, PhD, senior scientist at the Fatty Acid Research Institute and adjunct professor in the Department of Human Health and Nutritional Sciences at the University of Guelph and the Friedman School of Nutrition Science and Policy at Tufts University.

McBurney, a fellow of the American Society for Nutrition and the Canadian Nutrition Society, will present the findings at NUTRITION 2023, the American Society for Nutrition’s flagship annual meeting taking place July 2225 in Boston.

Using data from the UK Biobank, the researchers analyzed the self-reported hearing status and blood DHA levels of over 100,000 people aged 40-69 in the UK. After accounting for potential confounding variables, the results showed that people in the top quintile (one-fifth of participants) of blood DHA levels were 16 percent less likely to answer yes to the question are you hearing impaired than those in the bottom quintile of DHA levels. Similarly, those in the top quintile for DHA levels were 11 percent less likely to answer yes to the question do you have trouble following conversations when there is background noise than people in the bottom quintile for DHA levels.

Although the results show a significant association between DHA levels and hearing, McBurney cautioned that a cross-sectional population study does not provide enough evidence to conclusively conclude that DHA maintains hearing function or that inadequate DHA levels contribute to hearing loss. However, the findings add to a growing body of evidence for the importance of omega-3 fatty acids, including DHA in particular, in maintaining health and helping protect against age-related decline in a variety of bodily functions.

Omega-3s may help protect inner ear cell health or mitigate inflammatory responses to loud noises, chemicals, or infections. Similarly, previous studies in older adults and animals have suggested that higher levels of omega-3s are inversely related and may protect against age-related hearing loss.

Our bodies have a limited ability to produce DHA, so the amount of DHA found in our blood and tissues depends largely on our omega-3 intake. DHA levels can be increased by regularly consuming fish or taking dietary supplements.

There is strong evidence that higher blood levels of omega-3 fatty acids are beneficial, McBurney said. Oily fish and omega-3 supplements are both good dietary sources. If you choose to use a dietary supplement, compare products by reading the supplements fact panel for eicosapentaenoic acid (EPA)+DHA content.

An estimated 20% of people, over 1.5 billion people worldwide, suffer from hearing loss, and this number is expected to rise as the population ages over the next few decades. Hearing loss can range from mild to profound; it affects communication and social interactions, educational and employment opportunities, and many other aspects of daily life.

Environmental factors, genetic dispositions, and medications all contribute to hearing loss. Proven ways to reduce the risk of hearing loss include protecting your ears from loud noises using ear defenders and getting proper medical treatment for infections.

McBurney will present this research at 8:09 EDT extension Monday, July 24, during the Poster Theater Flash Session on Nutritional Factors in Aging and Chronic Disease at the Sheraton Boston, Fairfax.

Association of plasma omega-3 levels and prevalent hearing loss in the UK Biobank

Background: An estimated 1.57 billion people worldwide suffer from hearing loss (~20% of the population). Higher fish intake has been linked to age-related hearing loss in humans, and omega-3 fatty acid supplementation helped prevent hearing loss in mice.

Objectives: To evaluate the cross-sectional associations between plasma omega-3 fatty acids, i.e. docosahexaenoic acid (DHA) and self-reported hearing loss in the UK Biobank which collected data from questionnaires, biological samples and physical measurements on 502,639 individuals aged 40-69 years between 2007 and 2010. Among individuals with plasma DHA data (n=117,938), hearing data was available for 71 individuals. 368 and 115.303 [578y (meanSD); 54% female], depending on the result. DHA was measured as % of total plasma fatty acids by nuclear magnetic resonance. A yes to any of the following questions constituted evidence of some type of hearing loss: 1) Do you have a hearing impairment? 2) finds it difficult to follow a conversation if there is background noise, e.g. TV, radio, dinner, etc.; and 3) do you use a hearing aid most of the time? Logistic regression models were constructed based on the DHA quintile adjusted for age, gender, and plus additional demographic and medical history variables.

38% of 115,303 respondents reported hearing impairment, 26% of 113,134 reported hearing impairment due to background noise, and 5% of 71,368 respondents used hearing aids. People with the highest DHA levels (upper quintile) had a lower risk [Odds Ratio; OR (95% CI)] of hearing loss compared with those in the lowest group (lower quintile): hearing impairment, 0.89 (0.85, 0.94); hearing difficulty with background noise, 0.92 (0.88, 0.96); and hearing aid use, 0.80 (0.71, 0.90) in fully adjusted multivariate logistic regression models. Individuals in the top DHA quintile were 8 to 20 percent less likely to report hearing impairment (compared to the bottom quintile). Other cohorts should be explored to confirm the inverse association of plasma DHA with incident hearing loss, and the effects of increasing DHA intake on hearing metrics should be tested in randomized trials determining potential causal mechanisms.