We may be very familiar with the connection between nutrition and heart health, bone health, vision health, or even brain health. There is one relationship we rarely hear about, though (hint hint, pun intended). Yes, it's the connection between nutrition and hearing. You may be surprised to find out that there is, in fact, a strong relationship between the two.
It comes as no surprise, then, that the World Health Organization (WHO) reports hearing disorders as increasing rapidly without much concern or attention from neither society nor public health authorities. 1
The burden of hearing loss can be heavy, to say the least. Beyond medical and economic costs, it comes with social costs. It interferes with one's ability to communicate and form relationships. It can contribute to depression, anxiety, social isolation, delays in learning, and other issues. 2
Thankfully, in recent years, the auditory system is gaining more attention from nutrition science researchers who examine what nutritional factors can protect or repair hearing and what risk factors can damage hearing.
Of course, there are other major causes of hearing loss that are unrelated to nutrition and beyond the scope of this article - aging, exposure to loud noise, infections, certain drugs toxic to the ear (antibiotics, cancer treatment, pain killers), and many other causes. 1
While many nutritional factors and risk factors have been identified, much research still needs to be done to understand exactly what the mechanism is that causes certain nutrients or diets to influence hearing.
Antioxidants to Protect Hearing
One possible mechanism is that a better diet might protect the ear from being as vulnerable to the effects of aging. Hearing loss is common with aging and one reason is because, over the years, the inner ear continues to be exposed to more free radicals. An antioxidant-rich diet may prevent free radicals from forming in the inner ear because antioxidants scavenge free radicals, thus protecting the inner ear cells from being damaged.2
In fact, many studies have identified a relationship between hearing loss and several antioxidant vitamins - vitamins A, C, and E. Also, many of these studies have found magnesium to work in concert with these vitamins to protect hearing. 2
Other studies have suggested that antioxidants could also help protect against hearing loss from loud noise damage. It turns out that loud noise exposure can increase the amount of free radicals or unpaired electrons in the ear. (Picture these unpaired electrons as very unstable, highly active balls bouncing around a room uncontrollably damaging everything in their path.) These studies suggest it may be possible that higher concentrations of antioxidants in the blood can stop the production of these free radicals and reactive unpaired electrons, hindering them from damaging ear cells. 2,3
Excellent food sources of these nutrients include:
Vitamin A: Sweet potato, pumpkin, carrot, cantaloupe, mango, spinach, broccoli, kale, butternut squash, collards, herring, sockeye salmon
Vitamin C: Kiwi, pink and white grapefruit, orange juice, strawberries, bell peppers, broccoli, Brussels sprouts
Vitamin E: Olive oil, sunflower oil, sunflower seeds, almonds, hazelnuts, pecans, peanuts or peanut butter, wheat germ oil, mango, kiwi
Magnesium: pumpkin seeds, chia seeds, almonds, cashews, edamame, spinach, brown rice, black bans, potato, oatmeal
Nutritional Risk Factors to Avoid
What nutrients have been shown to have a negative effect on hearing? Studies reveal higher intake of carbohydrates, fat, and cholesterol can have a negative effect on hearing. How? Anything that might interfere with or damage blood supply to the cochlea can reduce hearing sensitivity. We all well know how these nutrients can interfere with our cardiovascular health. Well, the same principle applies to blood flow to the ear, specifically the cochlea.
On the flipside, studies suggest higher intakes of omega-3 polyunsaturated fatty acids can improve blood flow to the cochlea, thus improving hearing sensitivity. 4
Why does higher carbohydrate intake seem to negatively impact hearing? One study suggests this might have more to do with how high carbohydrate intake can increase blood triglyceride levels. A diet very rich in carbohydrates, especially concentrated sweets high in fructose or other sugars, can lead to high triglyceride levels in the blood. 11 One study found higher glycemic responses (high blood sugar levels) linked to an increased risk of hearing loss. 12
Obesity & Hearing
We have mostly discussed the role of specific nutrients in relation to hearing. Multiple recent studies, however, demonstrate that obesity, an excessive amount of body fat, is a risk factor for hearing loss. 5,6,7 This has even been demonstrated in adolescents. 8 While there is a need for more investigation into exactly how and why this occurs, it may be because excessive fatty tissue can cause strain on blood vessel walls. These walls need to be kept in good condition otherwise, in time, they can be damaged. This is especially true of the delicate blood vessel walls supplying the ear. 9Diet Patterns & Hearing
A study published in the Journal of Nutrition followed more than 81,000 women in the Nurses' Health Study II for 22 years. This amounts to greater than 1 million person-years of data. They examined their diet every 4 years, taking into account which diets were following the pattern prescribed by the DASH diet, the Alternate Mediterranean diet, or the Alternative Healthy Index diet pattern. 10
Despite minor differences, these diet patterns share much in common. They emphasize fruits, vegetables, seafood, poultry, seeds, nuts, beans and legumes, whole grains, and low-fat dairy. They discourage excessive salt, cholesterol, and sugar, and limit red meats and processed foods.
What did the study find? Women who followed these diet patterns closely had lower reports of hearing loss. This suggests a healthy diet might help lower the risk of hearing loss. 10.
It's clear and logical that, like any other organ or organ system in the body - our bones, our heart, our eyes, our digestive system, etc. - our ears and auditory system as a whole are also influenced by what we eat.
References
1. Olusanya, B. O., Davis, A. C., & Hoffman, H. J. (2019). Hearing loss: rising prevalence and impact. Bulletin of the World Health Organization, 97(10), 646–646A. https://doi.org/10.2471/BLT.19.224683
2. Jung, S. Y., Kim, S. H., & Yeo, S. G. (2019). Association of Nutritional Factors with Hearing Loss. Nutrients, 11(2), 307. https://doi.org/10.3390/nu11020307
3. Henderson D., Bielefeld E.C., Harris K.C., Hu B.H. The role of oxidative stress in noise-induced hearing loss. Ear Hear. 2006;27:1–19. doi: 10.1097/01.aud.0000191942.36672.f3.
4. Curhan S.G., Eavey R.D., Wang M., Rimm E.B., Curhan G.C. Fish and fatty acid consumption and the risk of hearing loss in women. Am. J. Clin. Nutr. 2014;100:1371–1377. doi: 10.3945/ajcn.114.091819.
5. Lee J.S., Kim D.H., Lee H.J., Kim H.J., Koo J.W., Choi H.G., Park B., Hong S.K. Lipid profiles and obesity as potential risk factors of sudden sensorineural hearing loss. PLoS ONE. 2015;10:e0122496. doi: 10.1371/journal.pone.0122496.
6. Kim T.S., Park S.W., Kim D.Y., Kim E.B., Chung J.W., So H.S. Visceral adipose tissue is significantly associated with hearing thresholds in adult women. Clin. Endocrinol. 2014;80:368–375. doi: 10.1111/cen.12184.
7. Kim S.H., Won Y.S., Kim M.G., Baek Y.J., Oh I.H., Yeo S.G. Relationship between obesity and hearing loss. Acta Otolaryngol. 2016;136:1046–1050. doi: 10.1080/00016489.2016.1179787.
8.Lalwani A.K., Katz K., Liu Y.H., Kim S., Weitzman M. Obesity is associated with sensorineural hearing loss in adolescents. Laryngoscope. 2013;123:3178–3184. doi: 10.1002/lary.24244.
9. Dhanda, N., & Taheri, S. (2017). A narrative review of obesity and hearing loss. International journal of obesity (2005), 41(7), 1066–1073. https://doi.org/10.1038/ijo.2017.32
10. Sharon G Curhan, Molin Wang, Roland D Eavey, Meir J Stampfer, Gary C Curhan, Adherence to Healthful Dietary Patterns Is Associated with Lower Risk of Hearing Loss in Women, The Journal of Nutrition, Volume 148, Issue 6, June 2018, Pages 944–951, https://doi.org/10.1093/jn/nxy058
11. Puga, A. M., Pajares, M. A., Varela-Moreiras, G., & Partearroyo, T. (2018). Interplay between Nutrition and Hearing Loss: State of Art. Nutrients, 11(1), 35. https://doi.org/10.3390/nu11010035
12. Gopinath B., Flood V.M., McMahon C.M., Burlutsky G., Brand-Miller J., Mitchell P. Dietary glycemic load is a predictor of age-related hearing loss in older adults. J. Nutr. 2010;140:2207–2212. doi: 10.3945/jn.110.128462.