Researchers from Brigham and Women's Hospital (BWH) and Schepens Eye Research Institute (SERI) found that the amount, type and ratio of essential fatty acids in the diet may play a key role in dry eye prevention in women. The study is published in the October 2005 issue of the American Journal of Clinical Nutrition.
Researchers found that a high intake of omega 3 fatty acids, often referred to as a 'good' fat, commonly found in fish and walnuts, is associated with a protective effect. Conversely, a higher ratio of omega 6, a fat found in many cooking and salad oils and animal meats, compared to omega 3 in the diet, may increase the risk of dry eye syndrome.
In this study, the researchers report the following specific findings:
* Women with the highest levels of omega 3 in their diets reduced their risk of dry eye syndrome by 20 percent compared to women with the lowest levels of this fat in their diet.
* A dietary ratio of omega 6 to omega 3 greater than 15:1 was associated with a 2.5-fold increased risk of dry eye syndrome in women. Currently, the average American diet consists of a similarly high ratio of omega 6 to omega 3 fatty acids.
* Tuna consumption reduced the risk of dry eye syndrome. Women who reported eating at least five servings of tuna per week had a 68 percent reduced risk of dry eye syndrome compared to women who consumed one serving per week.
* Other fish types that have lower levels of omega 3 fatty acids did not appear to protect against dry eye syndrome.
These findings are based on surveys completed by more than 37,000 women enrolled in the landmark, BWH-based Women's Health Study. Survey questions were designed to elicit information about an individual's history of diagnosed dry eye syndrome and dietary habits.