20 October 2005
Fat Intake Behind Dry Eye Syndrome?
Dry eye syndrome affects mainly women, with 8 million sufferers in the United States alone. It's a painful and debilitating eye disease but help may be at hand if researchers from Brigham and Women's Hospital (BWH) and Schepens Eye Research Institute (SERI) are correct in their assessment that the syndrome is related to dietary fat intake. The researchers found that the amount, type and ratio of essential fatty acids in the diet may play a key role in dry eye prevention. Their study appears in the American Journal of Clinical Nutrition.
Characteristics of dry eye syndrome are a decline in the quality or quantity of tears that normally bathe the eye to keep it moist and functioning well. The condition causes symptoms such as pain, irritation, dryness and a gritty sensation. If untreated, it can eventually lead to scarring or ulceration of the cornea, and loss of vision. The symptoms can be so severe that reading, driving, working and participating in other vision-related activities is difficult or impossible.
Researcher Biljana Miljanovic, from BWH, said that up until now there had been no hard information available for doctors to treat sufferers whose quality of life, productivity and safety was compromised. "Our study set out to examine how changing dietary habits in America, primarily a shift in the balance of essential fatty acids we are consuming, may be associated with onset of this eye disease. We 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," she said. The study made some interesting findings, including:
- Those 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 dietary intake.
- A 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. Unfortunately, the current average American diet consists of a similarly high ratio of omega 6 to omega 3 fatty acids.
- Consumption of tuna five times a week reduced the risk of dry eye syndrome by 68 percent.
- Other types of fish with lower levels of omega 3 fatty acids were less effective at protecting against dry eye syndrome.
"We are accustomed to the mantra 'you are what you eat' and our study suggests that this also applies to a person's vision," said co-researcher Debra Schaumberg, from SERI. "Based on this report, preventing dry eye syndrome is another potential reason to follow a diet rich in tuna and other foods plentiful in omega 3 fatty acids."
Source: Schepens Eye Research Institute