Visual System

Omega-3 docosahexaenoic fatty acid (DHA) is an important component of the membranes of retinal cells. This is the membrane that internally lines the eyeball and through which light impulses perceived by the eye are sent to the brain. 

By itself, the retina is particularly rich in long-chain fatty acids. Among these, DHA may constitute up to 50% of the fats in this tissue. For this reason, its involvement in visual function has been hypothesized.


Omega-3, lifelong benefits

In fact, an analysis of the results of 12 different studies, conducted by researchers at the Harvard School of Public Health in Boston, United States, and published in the journal Early Human Development , showed that as early as the age of two months, infants fed Omega-3-fortified milk have better visual abilities than other infants.

But visual tissue does not only need Omega-3s in the early years of life. Even as we age, the retina continues to need adequate amounts of these fatty acids. 

In fact, adiet that ensures the correct levels of Omega-3 reduces the risk of macular degeneration, a condition that, to date, is the most frequent cause of blindness in the world.

And even those with retinitis pigmentosa-an inherited retinal disease that causes progressive loss of night vision and peripheral visual field-can benefit from taking DHA.

This is shown by a study from Harvard Medical School in Boston, USA, which monitored the health status of patients aged 18 to 55 years, all of whom had the condition, for four years.

According to this research, if classic vitamin A therapy is supplemented with 1.2 grams per day of DHA, the course of retinitis pigmentosa is slowed for about two years.

Not only that, patients who have been on vitamin A therapy for at least two years can slow the decline in visual field sensitivity by adding 0.02 grams per day of omega-3 fatty acids to the treatment.


New hypotheses and new confirmations

Despite the amount of data already collected, studies on the benefits of Omega-3s for vision health have not yet stopped.

Specifically, results obtained during the Age-Related Eye Disease Study (AREDS)-a study sponsored by the U.S. National Eye Institute-showed that high doses of antioxidants-vitamin C, vitamin E, beta-carotene, and zinc-fight the progression of degenerative states of a specific area of the retina, the macula lutea.

The presence in the scientific literature of other studies suggesting that this same action could also be carried out by Omega-3s led the National Eye Institute to launch a second study, AREDS2, with the aim of evaluating the effectiveness of Omega-3s in slowing the progression of macular degeneration.