As far as hearing is concerned, formal research in the field of nutrition has been very limited, although more research has been carried out in recent years.Some studies date back to the 1930s and 1940s, but it was not until 1989 when it was suggested that diet can play a role in many age-related hearing disorders.
Some micronutrients thought to be significant included vitamins A, B complex, C, D, and E. Later studies added calcium, vitamin B12, iron, and folacin to the list. (Nutrients at a Glance contains more complete information on the vital importance of Vitamins and Minerals)
More nutrients are being added all the time. This only strengthens the belief that diet and nutrition are fundamental for optimal overall health, including the sense of hearing.
Nutrients Good for Hearing
Vitamins:
- A: Although vitamin A is known to play a significant part in many bodily functions, as far as hearing is concerned, a deficiency increases noise susceptibility and a decrease in sensory function. As far back as 1978, research showed that vitamin A is essential in inner-ear morphogenesis (development of the structure). Benefits have been seen in the hearing-impaired who have taken vitamin A supplements, including those with noise-induced hearing loss. The best form for the body is Beta-Carotene since the retinol forms can create toxic levels if too much is taken. The beta-carotene form will not do this no matter how much is taken. The only side effect if too much is taken is the skin will turn an orangey colour.
- B Complex: While B complex is well known to be vital for the health of nerves, it is equally so in helping to prevent hearing loss. A good B complex supplement can help reduce ear pressure and has been used to treat sudden deafness with profound hearing loss. In one study, subjects with sudden deafness were treated with vitamin B complex. Some recovered completely while others improved their hearing substantially. Tinnitus has also been studied. After several weeks, treatment was deemed to be successful.
The following is a break-down of how individual B vitamins can affect hearing.
NOTE: Do not take only one of the B vitamins without adding all the others since doing so will create deficiencies in one or more of the others, which can lead to other health problems. In other words, if you take niacin, for example, also include a B complex supplement.- Biotin: A deficiency produces many health-related disorders, including hearing loss. It has also been associated with long-term hearing and visual complications.
- Folacin: Although folacin is the official term, it can be quite confusing since other words are more commonly used, including folate and folic acid. Folate is used to encompass the entire group of folate vitamin forms: the natural folypolyglutamates found in food, and folic acid, the synthetic form added to dietary supplements and fortified foods. In any event, it is one nutrient commonly found deficient in those with hearing loss, especially the elderly who are often deficient in folacin as well as B12. When this happens, high levels of the toxin homocysteine form. This causes cholesterol deposits to build up on artery walls, reducing blood flow, nutrients, and oxygen to the heart and other organs, including the ears. Folacin supports energy production in hearing cells as well as increases circulation to the ears and elsewhere in the body. This deficiency is one of the main reasons people equate hearing loss with aging. Obviously, this need not happen.
- B1 (Thiamine): Thiamine not only enhances circulation but it also optimizes brain and hearing function. A deficiency is known to produce a delayed auditory brainstem response. A biotin deficiency is also thought to affect development of the auditory nerves. Therefore, it is essential that a diagnosis and treatment of a biotin deficiency is carried out in the first year of life.
- B2 (Riboflavin): B2 is thought to help the hearing cells use needed oxygen. To illustrate how important B2 is as far as the transportation of oxygen is concerned, hyperbaric oxygen treatments are now being recommended as the preferred treatment for sudden hearing loss, acute noise trauma from a car airbag, and Meniere’s disease.
- B3 (Niacin): In the body, niacin is converted into two active forms: NAD (nicotinamide adenine dinucleotide) and NADP (nicotinamide adenine dinucleotide phosphate), which are vital in the transfer of energy in cells. They are two of the most important coenzymes in the human cell involved in more than 50 different metabolic reactions. Niacin and its derivatives help nerve and hearing function cells operate at optimal levels by increasing circulation to the ears, as well as other parts of the body. It has been particularly helpful for those suffering from Meniere’s syndrome, associated with hearing loss and vertigo.
- B5 (Pantothenic acid): Pantothenic acid has been helpful to those suffering from tinnitus where it is thought to ‘coat’ nerve endings in the ear, thereby creating less of the agitating noise.
- B6 (Pyridoxine): According to PubMed, a B6 deficiency can affect peripheral and brainstem auditory pathways. B6 is also thought to be able to help regulate fluid levels in the ears.
- B12 (Cobalamin): B12 comes in various forms, but the methyl form is the one best used by the body, especially the central nervous system. Cyanocobalamin is the one most often found in nutritional supplements but then has to be converted by the liver. The conversion produces a significantly lesser amount. Therefore, it is best to use the methyl form. A Houston study published in the American Journal of Clinical Nutrition found that deficiencies in both B12 and folate, ones particularly common in the elderly, were likely associated with age-related auditory dysfunction. Deficiencies of these two B vitamins could affect both the nervous and vascular systems associated with hearing. A deficiency has also been associated with chronic tinnitus and noise-induced hearing loss. This led researchers to recommend that serum levels of vitamin B12 be evaluated in persons with tinnitus, noise-induced hearing loss, or age-related hearing loss. A deficiency of B12 may also inhibit myelination (outer covering) of the neurons in the cochlear nerve.
- C: In studies, vitamin C proved to be a highly beneficial antioxidant, particularly when combining it with glutathione as a protection against gentamycin ototoxicity. As much as two or three times the normal dosage was recommended during the drug treatment. Vitamin C was also found to help protect or lower the damage to cochlear hair cells and hearing caused by noise exposure. Vitamin C with bioflavonoids has long been used for proper immune function and, as a result, helps in preventing infections, including those in the ears.
- D: As far as hearing is concerned, a deficiency in this vitamin has serious consequences and has been associated with otosclerosis (abnormal bone growth in the middle ear), unexplained and bilateral cochlear deafness, presbycusis, and sensorineural hearing loss. Researchers had to conclude that vitamin D deficiency is likely one of the causes and supplementation should be considered in persons with hearing loss. Vitamin D can be inhibited if there is also a magnesium deficiency. If there is a magnesium deficiency, this will also affect calcium intakes. As you can see, not just one nutrient can be isolated as being a cause or cure of something.
- E: Vitamin E is a powerful antioxidant that increases circulation, beneficial to all parts of the body including the ear. A deficiency has also been associated with such neurological dysfunctions as abetalipoproteinaemia (also known as Bassen-Kornzweig syndrome) and other fat absorption disorders. Fats, especially alpha-linolenic acid (ALA an Omega-3 essential fatty acid) are vital for the auditory brainstem responses. Furthermore, if the body has problems with fats, there will also be deficiencies in the vitamins stored in fats: vitamin A, vitamin E, and vitamin K, which will cause a domino-effect in health that can also affect hearing. Good circulation depends on a rich supply of essential fatty acids. Excess saturated fat in the diet can interfere with this, as has been shown in children with hearing fluctuations which varied according to their fat intake. Essential fatty acids also helps reduce the tendency to produce excessive amounts of earwax.
Minerals
- Copper: Most people receive adequate amounts of copper from their diet. However, a copper-deficient diet has proven to have a detrimental effect on the auditory structures as well as the auditory startle response. Age-related cochlear hair cell loss is also enhanced when the diet is lacking in copper as well as zinc. Copper plays an important role in overall neurological health, including hearing; and a deficiency has been associated with hearing loss.
- Iodine: Although iodine deficiency is most commonly associated with goiter (an overgrowth of the thyroid gland), studies in animals and humans have found that an iodine deficiency also plays a role in sensorineural hearing loss, including middle ear changes, cochlear lesions, congenital deaf-mutism and bilateral hearing deficits, as well as high hearing thresholds in children. Having an adequate dietary intake of iodine during pregnancy is critical for fetal brain development, beginning about the 14th week and continuing perhaps into the third trimester. In Guizhou, China noted improvements in hearing were seen in otherwise normal school children in iodine-deficient areas following use of iodized salt. There has also been a noted relationship between urinary iodine concentration and hearing capacity in children. Although iodine is available in ordinary salt, some iodine contents are deliberately lowered in some types of table salt in an effort to compensate for the excessive use of table salt by many persons. Certain medical conditions also require strict limitation of dietary salt, further reducing intake of iodine. However, it should be noted that not much is usually needed by the average person.
- Iron: Iron deficiency is fairly common and can result from several causes including too little dietary iron, poor absorption of iron, or chronic or acute bleeding. (See more info on amemias.) Several studies have been conducted where results showed an association with iron deficiency and several hearing abnormalities, including damage to the inner ear cells and sensorineural hearing loss, elevated auditory thresholds, as well as noise-induced hearing loss and cochlear deafness.
Caution: On the other hand, some research focused on the role of iron in gentamicin-induced ototoxicity. Gentamicin, and similar drugs, is a commonly used antibiotic worldwide, despite its known toxicity to the inner ear. In these studies, gentamicin combined with iron actually produced free radicals and ototoxicity. - Magnesium: Magnesium helps support healthy nerve function in the auditory system, prevents damage to the inner ear hair cells, and protects the arterial linings from physical stress. Studies have shown that this mineral has some protective benefits against noise-induced hearing loss with faster recovery from hearing threshold shift and a significant reduction of trauma caused by high levels of noise exposure, as well as a reduction in ischemia-induced hearing loss. A deficiency did show a significant decrease in these protective benefits.
- Manganese: Some nutritionists have noted a relationship between a deficiency in manganese and that of ear noises and diminished hearing.
- Potassium: A healthy nervous system and proper transmission of nerve impulses to all parts of the body, including the ear, is dependent upon potassium.
- Zinc: This essential mineral is vital for many functions that occur in the body including the support of the immune system, but research is finding that it also protects hair cells in the inner ear. The relationship between zinc deficiency and tinnitus, cochlear damage, and hearing damage has been studied in both humans and animals. Zinc deficiency increases the vulnerability of the cochlea to hearing loss associated with normal aging. Research results indicate that zinc deficiencies increase the vulnerability of the cochlea to damage associated with normal aging. When a zinc supplement was given, one-third of the elderly patients showed marked improvement in tinnitus caused by presbycusis and sensorineural hearing loss. One interesting finding was that researchers found that tinnitus occurred in 13% of children who passed audiometric screening texts, in 23% to 60% of children with hearing loss, and in 44% of children with secretory otitis media. Only 3% of children complain about tinnitus because they do not consider it to be abnormal. According to at least one researcher, tinnitus might be a factor in behavioral problems in children.
Amino Acids
- Arginine: Many health-related functions are attributed to this essential amino acid, including protection against sensorineural hearing loss and cochlear damage caused by the toxins produced by Streptococcus pneumoniae infections. A deficiency does have an effect on the inner ear in Reye’s syndrome. However, not everyone should take arginine supplements, which is why supplementation needs to have professional medical supervision. But if it is used as a supplement, it is advised to take antioxidants as well.
- Carnitine: Acetyl-L-carnitine is a favorite anti-aging amino acid and closely related to the B vitamins. However, it is also being recognized as having a beneficial effect on diabetes-induced brain stem auditory deficits. Acetyl-L-carnitine is the preferential form because of its superior absorption and because it plays a key role in the transport of fatty acids from inside to cell to the mitochondria in the inner ear, a crucial step for energy production. Studies have shown that it also improved hearing in aged subjects.
- Cysteine: N-acetyl-cysteine is the amino acid form best utilized by the body. It helps protect critical hearing cells in the inner ear. As an antioxidant and glutathione precursor, it has many important functions including the preservation of hearing. Studies have shown that noise levels normally causing severe and permanent hearing loss will result in little or no damage when n-acetyl-cysteine is taken. It is also known to protect various parts of the body, including the sense of hearing, from certain medical and cancer treatments as well as the ototoxic effects of cisplatin. (See The Laryngoscope 2001.)
- Glutathione: A deficiency of this amino acid can increase the risk of noise-induced hearing loss. Replenishing it reduces the damage. Another protective benefit is that it protects against gentamicin ototoxicity, which often induces damage to the cochlear. Studies have shown that aging causes a severe reduction in glutathione levels, especially in the auditory nerve.
- Histidine: An essential amino acid, histidine is vital in the maintenance of the myelin sheaths surrounding nerves, including the auditory nerve and used to treat some forms of hearing disability. Consequently, where there is a deficiency of histidine, nerve deafness is likely. A deficiency is also associated with overall hearing loss.
- Methionine: An amino acid with antioxidant properties, methionine has been found to have important protective benefits to both auditory hair cells and auditory neurons from various types of ototoxic hearing loss, especially from aminoglycosides, ionic platinum compounds, and cisplatin. Since methionine is the precursor to homocysteine in the body, folic acid and vitamins B12 and B6 should also be taken to protect against an excess accumulation of homocysteine. High homocysteine levels coupled with low B vitamin levels interfere with blood flow to the inner ear.
- Taurine: Taurine is a semi-essential amino acid, meaning that it is only essential under certain circumstances. A deficiency does take time to develop but can cause lasting effects, especially in infants who are not able to obtain the nutrient from their diets. Infants with inadequate dietary taurine have shorter auditory brain stem responses, but those who received a diet rich in the nutrient, showed earlier maturation of the brainstem auditory response.
Co-Enzymes
- Alpha lipoic acid: It is a powerful antioxidant which protects against free-radical damage, supports nerve system function, and plays an essential role in generating mitochondrea in the hair cells of the inner ear. It has also been shown to improve overall energy and age-related hearing losses. Presently its primary therapeutic use is for the treatment of diabetic induced nerve dysfunction (neuropathy). Alpha lipoic acid converts to DHLA (dihydrolipoic acid) which is known to recycle glutathione which, in turn, recycles vitamin E. Because it has such powerful action against free-radicals, there is also evidence that it plays an important role in reducing presbycusis and improving cochlear function, as well as providing protection against noise and auditory toxicity caused by ototoxic drug therapies.
- Co-enzyme Q10: It is another powerful antioxidant similar to vitamin E which helps to maintain circulation to the ears as well as supporting energy production in hearing cells, and protecting against free-radical damage. Known for improving function to heart patients, CoQ10 is also showing promise as a component necessary for preventing progressive hearing loss in diabetics without affecting other diabetic complications or clinical symptoms. Studies are showing that CoQ10 is also effective in promoting recovery from acute sudden deafness resulting from hypoxia (insufficient oxygen) as well as in the recovery of damaged auditory hairs and in preventing respiratory metabolic impairment of the hair cells caused by hypoxia. Other studies showed that CoQ10 had an effect on neurosensory deafness resulting from maternally inherited diabetes mellitus and deafness.
- NAD (nicotinamide adenine dinucleotide): This important coenzyme is formed from niacin (vitamin B3), which provides the nicotinamide in NAD (nicotinamide adenine dinucleotide). NAD, and its derivatives, are all vital in the transfer of energy in cells. It helps nerve and hearing function cells perform at optimal levels.
- Pregnenolone: Although its functions are not well known, it has been suggested that pregnenolone serves as a precursor or ‘mother steroid’ to other hormones, including DHEA (dehydroepiandrosterone) and progesterone. Pregnenolone is synthesized in both the adrenal glands and in cells of the central nervous system as well as in the liver, skin, testes and ovaries. Since pregnenolone, like other hormones, diminishes during the aging process, it is understandable why supplementation would improve overall health, including visual and hearing acuity in many people.
Caution: Technically, pregnenolone can cause disturbances in the endocrine system. This may appear as changes in the menstrual cycle or the development or aggravation of such hormone sensitive diseases as breast or prostate cancer. The side effects and interactions with other therapies are currently unknown. Therefore, relying on this substance solely for the purpose of improving one’s hearing may not be the best idea.
Herbs
Herbs are meant to be used as medicines and should not be routinely consumed for long periods of time.
- Butchers broom: This herb can help support circulation to the ears and control fluid levels.
- Ginkgo biloba: This herb is better known for enhancing the memory, as well as a wide range of other health benefits. This may be because it helps promote blood flow, which works well for the circulation to the ears. It also seems to help to maintain balance in addition to other hearing disorders, including tinnitus, and has been shown to have a protective effect against gentamicin-induced cochlear damage and cisplatin-induced toxicity.
GreenMedInfo has a list of abstracts (studies) of nutrients that help hearing loss and substances that affect hearing.
