Published May 12, 2009
New research published today suggests that eating fish, nuts, olive oil and other foods rich in omega-3 fatty acids and avoiding trans fats may help reduce the risk of a common eye disorder called age-related macular degeneration, or AMD.
AMD arises from gradual damage to the macula, a structure on the retina that allows for seeing fine detail. AMD is the leading cause of vision loss in the elderly.
Among 2,454 participants in the long-running Blue Mountains Eye Study, researchers found that eating one serving of fish per week was associated with a 31 percent lower risk of developing early AMD, after adjusting for the potential influence of age, sex and smoking — the only consistently reported modifiable risk factor.
Eating one to two servings of nuts per week was associated with a 35 percent lower risk of early AMD, they also found.
Jennifer S. L Tan, of Westmead Hospital, University of Sydney, Australia, and colleagues say their findings support the hypothesis that boosting intake of omega-3 polyunsaturated fatty acids and eating fish and nuts regularly "may protect against the development of early AMD."
Further studies are needed to determine whether changing a person's diet or recommending supplementation could prevent or delay the development of AMD, they conclude in a report in the journal Archives of Ophthalmology.
In a related study in the journal, Dr. Elaine W.-T. Chong, of the Centre for Eye Research Australia, and colleagues report that a diet with large amounts of foods containing unhealthy trans fats may raise the risk of AMD.
Among 6,734 people who provided information on diet in the early 1990s when they were ages 58 to 69 years old and were then tracked for the development of AMD until between 2003 and 2006, a total of 2,872 developed early AMD and 88 developed late AMD.
According to Chong and colleagues, people who consumed the most trans-unsaturated fats, found in baked goods and processed foods, were 76 percent more likely to have late AMD than people who consumed the least trans-unsaturated fats.
They also found that people who consumed the most omega-3 fatty acids were 15 percent less likely to have early AMD than those who consumed the least omega-3 fatty acids.
Consuming 100 milliliters or more per week of olive oil (versus less than 1 milliliter per week) lowered the odds of late AMD by 52 percent, the researchers say.
There were no significant ties between intake of fish, total fat, butter or margarine and the development of AMD.
"Our findings suggest that people who follow a diet low in processed foods high in trans-unsaturated fatty acids and rich in omega-3 fatty acids and olive oil might enjoy some protection from developing AMD," Chong's team concludes.