Retinitis pigmentosa, Omega-3s slow vision loss by 40%
Retinitis pigmentosa: course greatly slowed thanks to fish oil
The combination of a diet rich in omega-3 fatty acids and taking vitamin A supplements can greatly slow vision loss in those suffering from retinitis pigmentosa. Researchers at Harvard University (Boston, United States) made the discovery, thanks to data collected during a study published in the Archives of Ophthalmology. Indeed, the research found that consumption of at least 0.2 grams per day of Omega-3 reduced the rapidity of loss of the ability to see at a distance by 40 percent each year. According to the group of U.S. scientists, led by Eliot Berson, this effect could ensure that patients maintain their vision for 18 years longer.
Retinitis pigmentosa and vision loss
Retinitis pigmentosa is a genetic disease that affects the eyes. Suffering from it is one in every 4,000 inhabitants, with a total of 2 million individuals affected by the disease worldwide. This disease causes night blindness as early as adolescence. In young adults, the situation worsens, turning into loss of side vision. Further worsening of symptoms is manifested by the restriction of the eye's ability to tunnel vision, allowing it to see only what is in the central part of the visual field. There is currently no effective cure for this disease, and blindness usually occurs by age 60.
The clinical study
The Harvard researchers' discovery was made possible by 3 clinical trials involving, in total, 357 patients with retinitis pigmentosa. All participants were taking a daily vitamin A supplement in the form of palmitate. Berson and colleagues showed that in individuals who, in addition to vitamin A, also take at least 0.2 grams per day of Omega-3, the decrease in distance visual acuity occurs at a 40% lower rate than observed in those who introduce low amounts of these nutrients. Intake of Omega-3 can reduce the rapidity of loss of sensitivity in the central part of the visual field by about 50 percent.
The benefits of omega-3s for vision
Based on these findings, the researchers concluded that the combination of adiet rich in Omega-3 and vitamin A intake could enable many individuals with retinitis pigmentosa to maintain both visual acuity and a good central visual field for most of their lives. In fact, the action of Omega-3 and vitamin A would allow the preservation of central retinal function. In particular, Berson hypothesizes that the action of vitamin A is made possible bydocosahexanoic acid (DHA), an Omega-3 found infish oil. In retinitis pigmentosa, degeneration of the rods-elements of the eye that are essential for vision-would lead to a deficiency of both vitamin A and DHA. Intake of the two nutrients would counteract the vision damage resulting from this situation.
Source
1. Berson EL, Rosner B, Sandberg MA, Weigel-DiFranco C, Willet WC, "Omega-3 Intake and Visual Acuity in Patients With Retinitis Pigmentosa Receiving Vitamin A," Arch Ophthalmol., Published online ahead of print, doi:10.1001/archopthalmol.2011.2580
