Omega 3 Fatty Acids in Fish Oil Reduce Incidence of Age-related Macular Degeneration

A recent study of a large population of women showed that regular consumption of fish and EPA and DHA (omega-3 fatty acids found in fish) was associated with a significant decrease in the risk of age-related macular degeneration, a major cause of blindness.

Age-related macular degeneration (AMD), a major cause of blindness, is estimated to affect 9 million U.S. adults. Evidence from observational and epidemiologic studies suggest an inverse relation between regular dietary intake of fish and DHA and EPA and the risk of advanced AMD.
In a recent study published online in the Archives of Ophthalmology, researchers examined whether the intake of omega-3 fatty acids and fish affects the incidence of AMD in women.

A detailed food-frequency questionnaire was completed by 38,022 women at an average age of 54.6 years. All women were free of a diagnosis of AMD at the beginning of the trial. After an average of 10 years follow-up, 235 cases of AMD were confirmed.

Women in the highest third of intake of DHA, compared to those in the lowest, had a 38% decreased risk of AMD. Those with the highest third of intake of EPA had a 34% decrease risk of AMD. Similarly to intakes of individual omega-3 fatty acids, women who consumed 1 or more servings of fish per week had a 42% decreased risk in comparison to those who ate less than 1 serving per month.

The results from this prospective study from a large population of women indicate that regular consumption of fish and omega-3 fatty acids from fish (EPA and DHA) significantly reduces the risk of AMD. This is some of the strongest evidence to date that support a role for long-chain fatty omega-3 fatty acids in the primary prevention of AMD, and possibly a reduction in the number of people who ultimately have advanced AMD, potentially leading to blindness.

William G. Christen, ScD et al. Dietary omega Fatty Acid and Fish Intake and Incident Age-Related Macular Degeneration in Women. Arch Ophthalmol. Published online March 14, 2011. doi:10.1001/archophthalmol.2011.34

High Glycemic Load Diets Increase Risk of Age-Related Hearing Loss

In a recent study of adults over 50 years old, those with a high glycemic load diet had a significantly increased risk of age-related hearing loss.

Age-related hearing loss is a common disability in older adults, and nutrition may play a role in the development of this condition. Carbohydrate nutrition is thought to possibly relate to age-related hearing loss.

In a recent issue of the Journal of Nutrition, researchers sought to determine the association between glycemic index (GI) and glycemic load (GL) and age-related hearing loss.

Hearing loss was measured in 2956 participants aged 50 years or older enrolled in the Blue Mountains Hearing Study. Food frequency questionnaires were used to document intakes of carbohydrates, sugar, starch, cereal and total fiber. Australian GI values were used to calculate average GI and GL values of the diets.

A higher average dietary GI was associated with a 59% increased prevalence of any hearing loss. Participants in the highest 25% of average dietary GL intake compared with those in the lowest 25% had a 76% greater risk of developing hearing loss. Higher carbohydrate and sugar intakes were also associated with occurrence of hearing loss.

In this study group, a high-GL diet was a predictor of hearing loss, as was higher intake of total carbohydrates. It is possible that prolonged high blood glucose levels after a meal may be an underlying biological mechanism in the development of age-related hearing loss.

Gopinath B, et al. Dietary Glycemic Load Is a Predictor of Age-Related Hearing Loss in Older Adults. 2010. J Nutr 140(12):2207-12.