Last year I mentioned a couple of studies which found a link between folate and age-related hearing loss. Now, a newly published study in the American Journal Of Clinical Nutrition (1) has found that fish consumption and long chain omega 3 fatty acids, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), which are found in oily fish such as salmon, mackerel, sardines and trout, may protect against age-related hearing loss (known as presbycusis).
The study scientists (1) wanted to determine the association between dietary intakes of fish and long chain omega 3 fatty acids and the risk of age related hearing loss. They used a population of individuals from a study known as ‘The Blue Mountains Hearing Study’ and collected data via a specially designed food frequency questionnaire in order to estimate fish and omega 3 intakes. In almost 3000 participants, aged 50 or over, age related hearing loss was measured. It was found that there was an inverse association between total long chain omega 3 fatty acid intake and prevalence of hearing loss i.e. those individuals with the highest intakes of long chain omega 3 fatty acids had the lowest prevalence of hearing loss. The scientists also found that individuals who ate 2 or more servings of fish a week had a significantly reduced risk, 42% reduced risk, of developing age related hearing loss when compared to individuals who ate less than one serving a fish per week.
The researchers conclude “There was an inverse association between higher intakes of long-chain n–3 PUFAs [Polyunsaturated Fatty Acids] and regular weekly consumption of fish and hearing loss. Dietary intervention with n–3 PUFAs could prevent or delay the development of age-related hearing loss” (1)
In another recent study (2) researchers looked at blood plasma levels of long chain omega 3 fatty acids to see if there was an association with age-related hearing loss. The study included 720 men and women aged between 50 and 70 years old and lasted 3 years. It was found that individuals with the highest levels of blood plasma long chain omega 3 fatty acids has less hearing loss in the low frequencies (but not high frequencies) over three years than individuals with the lowest levels of omega 3 fatty acids. The association held firm even after the researchers adjusted for potential confounding factors such as baseline mean hearing thresholds, age, sex, level of education and alcohol consumption. The researchers conclude that “This study is the first to show an inverse association between plasma very long-chain n-3 PUFAs and age-related hearing loss. These results are encouraging, but require confirmation from future studies”.
It is not yet known how the omega 3 fatty acids might be acting but these fats are highly active molecules and could be working via a number of different mechanisms in the body e.g. through their anti-inflammatory actions. Both of these studies are interesting and point toward a potential use for omega 3 fatty acids to delay, or prevent against, age related hearing loss. However, the studies do only show an association and do not prove that omega 3 fatty acids can prevent age related hearing loss. Further studies would be needed before any recommendations could be made for the use of long chain omega 3 fatty acids for the prevention of age-related hearing loss. As you will know from my numerous past blog posts, omega 3 fatty acids are vital to health for a vast number of reasons and including oily fish weekly as part of a healthy balanced diet would certainly seem sensible. Sadly many people in the UK do not regularly consume oily fish. On average, adults in the UK are eating 1/3 of a portion of oily fish per week, with 70% of adults eating no oily fish at all. The Government advises that individuals aim to eat at least two portions of fish a week, one of which should be oily (3). Supplements can never be viewed as an alternative to a healthy diet but if you do not regularly eat fish you might want to consider talking to your GP or nurse about taking a fish oil supplement. For vegetarians and vegans a flaxseed oil supplement could be considered (to provide the short chain omega 3 fat alpha-linoleic acid). Also, there are now a few companies who make vegetarian and vegan EPA and DHA from algal sources, a very exciting development and well worth investigating if you wish to take an omega 3 supplement.
(1)Bamini Gopinath B et al. 2010. Consumption of omega-3 fatty acids and fish and risk of age-related hearing loss. American Journal of Clinical Nutrition. 92: 416-421
(2)Dullemeijer C et al. Plasma very long-chain n-3 polyunsaturated fatty acids and age-related hearing loss in older adults. J Nutr Health Aging. 14(5):347-51.
(3) (4)British Nutrition Foundation. http://www.britishnutrition.org.uk/home.asp?siteId=43§ionId=593&subSectionId=322&parentSection=299&which=1
Written by Ani Kowal
Related posts:
- Higher folate levels recently linked to reduced risk of hearing loss
- Fish and fish oils may be important for bone health
- Study links fish and omega 3 fats to reduced risk of age-related macular degeneration in women
- Omega 3 fish oils linked to a reduced risk of colon cancer
- More evidence suggests that eating oily fish might protect the eyes
