N-3 Fatty Acid Intake Curbs Risk of Dry Eyes

NEW YORK (Reuters Health) - Women who consume more n-3 fatty acids may reduce their risk of dry eye syndrome, the results of a new study suggest.

Dry eye syndrome is a condition in which the tears that normally bathe the eye fail to do their job, which can lead to corneal damage and vision problems. People who wear contact lens often suffer from the condition, as do those who have undergone laser procedures to correct their vision. Women going through menopause also frequently develop dry eye syndrome.

There is little information available on risk factors for dry eye syndrome, and currently no approach to preventing the condition, Dr. Debra A. Schaumberg of Brigham and Women's Hospital in Boston and colleagues report in the American Journal of Clinical Nutrition. Artificial tears, the most commonly used therapy, provide only temporary relief.

Since inflammation is known to be involved in dry eye syndrome, and there is evidence that n-3 fatty acids can protect against inflammation, the researchers analyzed the relationship between dietary intake of n-3 and n-6 fatty acids and dry eye syndrome among health professionals participating in the Women's Health Study.

Of the 32,470 women included analyses, 4.7 percent reported dry eye syndrome. Women in the highest quartile for n-3 intake were at 17 percent lower risk of the syndrome than women in the lowest intake quartile.

Eating more tuna also appeared to protect against dry eye syndrome, with women who consumed five to six or more 4-ounce servings a week at 68 percent lower risk compared with women who ate one serving of tuna or less weekly. No other types of fish or seafood were associated with dry eye syndrome risk.

The researchers also found that women with the highest ratio of n-6 to omega-3 fatty acid intake were at 2.5-fold greater risk of dry eye syndrome.

They conclude: "In light of the plausibility of hypothesized biological mechanisms, these findings suggest that increasing dietary intake of n-3 fatty acids may reduce the risk of dry eye syndrome, an important and prevalent cause of ocular complaints."

SOURCE: American Journal of Clinical Nutrition, October 2005.