Two new studies have found as association between eating foods high in omega-three fatty acids, and reducing the risk eye diseases like age-related macular degeneration.

In the first study, researchers found that eating foods containing omega-three fatty acids, such as nuts, appeared to reduce the risk of age-related macular degeneration - the leading cause of blindness in the elderly.

The participants completed a questionnaire about the foods they ate regularly. Digital photographs of the retina were taken at the start of the study and again five and 10 years later to track the development of age-related macular degeneration.

The results showed that after adjusting for other risk factors, people who ate one serving of fish per week had a 31% lower risk of early signs of AMD. Those who ate one to two servings of nuts rich in omega-3 fatty acids had a 35% lower risk.

Age-related macular degeneration is a condition where the central vision is lost as cells at the back of the eye degenerate over time or new blood vessels grow and bleed.

Writing in the Archives of Ophthalmology, one of the authors said: "In conclusion, our findings support the hypothesis that increased intake of omega-three polyunsaturated fatty acids and regular consumption of fish and/or nuts in the diet may protect against the development of early AMD."

It is thought fatty acids may protect the eyes by preventing the build-up of plaque in the arteries or reducing inflammation, blood vessel formation and oxygen-related cell damage in the retina.

The second study, published in the same journal, found that eating a Mediterranean-style diet rich in fish, nuts, and olive oil is also linked to saving your eyesight and helping to prevent age-related macular degeneration (AMD).

Researchers found people who ate higher levels of trans fats more often found in baked goods and processed foods were more likely to develop late-stage age-related macular degeneration. In addition, those who ate the most omega-3 fatty acids through olive oil were less likely to have AMD. They concluded that "A diet low in trans-unsaturated fat and rich in omega-3 fatty acids and olive oil may reduce the risk of AMD."

Trans fats have been shown to increase the risk of inflammatory diseases like heart disease, and researchers think that these fats may also have a similar effect on the blood vessels in eyes.

In contrast, olive oil contains heart-healthy omega-3 fatty acids along with other beneficial compounds such as antioxidants and anti-inflammatory components that are associated with helping protect the blood vessels in the eyes and reducing the risk of age-related macular degeneration.

Research paper details:

• Tan JSL,Wang JJ, Flood V, Mitchell P. Dietary fatty acids and the 10-Year Incidence of Age-Related Macular Degeneration: The Blue Mountains Eye Study Arch Ophthalmol. 2009;127(5):656-665.

• Chong EW, Robman LD, Simpson JA, et al. Fat Consumption and Its Association With Age-Related Macular Degeneration Arch Ophthalmol. 2009;127(5):674-680.