More Good Fat, Less Bad, Reduces Age-Related Macular Degeneration Risk
More good fat, less bad, reduces age-related macular degeneration risk Two reports published in the May, 2009 issue of the American Medical Association journal Archives of Ophthalmology reveal a protective effect for omega-3 fatty acids, fish, nuts and olive oil, and an adverse effect for trans fatty acids, on the risk of developing age-related macular degeneration (AMD), a leading cause of vision loss in older individuals.
In the first study, Jennifer S.L. Tan, MBBS, BE at the University of Sydney, Australia and her colleagues evaluated data from 2,454 participants in the Blue Mountains Eye Study of men and women aged 49 and older. Those who consumed one serving of fish per week were shown to have a 31 percent lower adjusted risk of developing early AMD compared with those who consumed less.
In the second article, Elaine W. T. Chong, MD, PhD, of the Centre for Eye Research Australia and her associates evaluated data from 6,734 men and women aged 58 to 69 who participated in the Melbourne Collaborative Cohort Study. Dietary questionnaires completed between 1990 and 1994 were analyzed for the intake of various foods and individual fatty acids.
Follow up examinations conducted between 2003 and 2006 detected 2,872 cases of early age-related macular degeneration and 88 cases of late disease.
A high intake of trans-unsaturated fats was associated with a significant increase in late macular degeneration, with those whose intake was categorized as among the top 25 percent of participants having a 76 percent greater risk than those whose intake was among the lowest fourth.
Olive oil emerged as protective against no late disease. When those who reported consuming at least 100 milliliters per week olive oil were compared with those who consumed less than 1 milliliter per week, they were found to have a 52 percent lower risk of late AMD.
For early AMD, those whose omega-3 fatty acid intake was among the top 25 percent had a 15 percent lower risk compared with those whose intake was among the lowest quarter.
Trans fatty acids increase cholesterol levels and inflammation, both of which affect the eyes’ blood vessels, while omega-3 fatty acids may help protect the retina. Although the main fats contained in olive oil were not associated with macular degeneration risk, the oil contains antioxidants and anti-inflammatory compounds that could be protective. “A diet low in trans-unsaturated fat and rich in omega-3 fatty acids and olive oil may reduce the risk of AMD,” the authors conclude.