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

Omega–3 Fatty Acid Intake & The Incidence of Age-related Macular Degeneration

Results recently published from a long-term study indicate that people at risk for age-related macular degeneration (AMD) may significantly reduce the risk of this disease by increasing their dietary intake of omega-3 fatty acids from oily fish, nuts and seeds, and fish oil supplements.

Omega-3 fatty acids are important for the vascular and neural health of the retina and may influence the risk of developing age-related macular degeneration (AMD). There are two forms of AMD: dry and wet. In the dry form, normal tissue in the macula slowly disappears, leaving a pale area referred to as central geographic atrophy (CGA). In the wet form, or neovascular (NV) AMD, abnormal blood vessels grow underneath the macula. These vessels leak serum or blood and eventually cause the normal macular tissue to be replaced by scar tissue.

Researchers recently investigated whether omega-3 fatty acid intake was associated with a reduced risk of developing both wet and dry forms of AMD. The study involved 1837 people from the Age-Related Eye Diseases Study (AREDS) who were at moderate to high risk of developing AMD. Clinical measurements were obtained in this group over a period of 12 years (from 1992 to 2005).

Participants who reported the highest omega–3 fatty acid intake were 35% less likely than their peers to develop dry (CGA) AMD, and 32% less likely to develop the more common, wet form (NV) AMD.

Over the 12 years of this study, the incidence of CGA and NV AMD was lowest for those reporting the highest consumption of omega-3 fatty acids, which are found primarily in oily fish, nuts and seeds, and fish oil supplements. If these results are applied to the general population, dietary intervention may have a significant preventive effect on the development and progression of AMD.

Am J Clin Nutr. 2009 Dec;90(6):1601-7


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Compound From Olive Fruit Shows Heart Health Potential

New research shows portion-controlled meal replacement diets as more effective than standard diets at both initial weight loss and long-term weight maintenance in type 2 diabetics.
In a recent study, supplementing with hydroxytyrosol – a polyphenolic compound extracted from olives – correlated with higher activity levels of the enzyme arylesterase, an antioxidant biomarker, and lower levels of oxidized LDL cholesterol. Oxidized LDL is believed to be a major player in promoting atherosclerosis (the build-up of fatty plaques in arteries) and general cardiovascular disease.

Hydroxytyrosol is thought to be the main antioxidant compound in olive fruit, and it is believed to play a significant role in many of the health benefits attributed to olive oil. Previous research has linked the compound to cardiovascular benefits, typically reductions in LDL or “bad” cholesterol. Data has also suggested the compound may boost eye health and reduce the risk of macular degeneration.

Spanish researchers reported these most recent results in the British Journal of Nutrition. Twenty-two healthy volunteers between 20 and 45 years of age and with a BMI between 18 and 33 kg/m2 were recruited. Volunteers were randomly assigned to receive 10 to 15 grams per day of hydroxytyrosol-enriched sunflower oil or non-enriched sunflower oil for three weeks. The former provided a daily hydroxytyrosol dose of between 45 and 50 mg. After the initial three week period, volunteers had two weeks of no intervention before crossing over to receive the other intervention.

Results showed no changes in total, LDL, or HDL-cholesterol between the groups. However, consumption of the hydroxytyrosol-enriched sunflower oil produced significant reductions in oxidized LDL from 79.8 units per liter at the start of the study to 64.1 U/l after three weeks, compared to an increase from 72.7 to 86.4 U/l during the control phase. Furthermore, the activity of arylesterase increased from 235.2 to 448.9 U/l during the hydroxytyrosol phase, compared with an increase from 204.1 to 310.3 U/l during the control phase.

The researchers reported that although hydroxytyrosol-enriched sunflower oil did not significantly reduce LDL-cholesterol or increase HDL-cholesterol, it acted as a functional food by increasing arylesterase activity and reducing oxidized LDL. Based on these results, dietary sources of hydroxytyrosol appear to be capable of reducing certain risk factors associated with coronary artery disease.

Vazquez-Velasco M, et al. Effects of hydroxytyrosol-enriched sunflower oil consumption on CVD risk factors. 2010. Br J Nutr, ePub ahead of print. doi: 10.1017/S0007114510005015