Increasing the dietary intake of Omega 3 fatty acids, found in certain kinds of fish, nuts and vegetable oils, may protect one from blindness, suggests a study conducted on mice.

Scientists in Boston found that they have a protective effect against blindness resulting from abnormal blood vessel growth in the eye, according to the study published in the online journal Nature Medicine.

Human clinical trials will soon begin at a children's hospital in Boston to test the effects of Omega 3 supplementation in premature babies who are at risk for vision loss, the researchers were quoted as saying by science portal EurekAlert.

Omega 3 fatty acids are already known to be beneficial for heart and brain functions. Short-term studies have indicated that taking dietary supplements of Omega 3 could also lower blood pressure in people with hypertension.

Abnormal vessel growth is the cause of retinopathy - an eye disease that leads to the eventual loss of vision. It begins with a loss of blood vessels in the retina, which becomes oxygen starved, sends out alarm signals and spurs new vessel growth. But the new vessels grow abnormally and are malformed, leaky and over-abundant.

The abnormal vessels finally pull the retina away from its supporting layer, and this retinal detachment ultimately causes blindness.

The researchers, led by Lois Smith and Kip Connor of Children's Hospital in Boston and Harvard Medical School, and John Paul SanGiovanni of the National Eye Institute (NEI) studied retinopathy in mice, feeding them a diet rich in Omega-3 fatty acids.

Mice on the Omega 3 diet had less initial vessel loss in the retina than those fed with Omega 6 fatty acids. The area with vessel loss was 40-50 percent smaller.

"Our studies suggest that after initial loss, vessels re-grew quickly and efficiently in the Omega 3-fed mice," Connor said.

"This increased the oxygen supply to retinal tissue, resulting in a dampening of the inflammatory 'alarm' signals that lead to pathologic vessel growth."