How Omega-3 Helps Prevent Age-Related Vision Loss
Age-related vision loss is a natural process, caused by a number of factors and affecting each person in different degrees. Now a research team at the University of Alberta has discovered that an omega-3 fatty acid in fish prevents the accumulation of a toxin called lipofuscin, which can lead to age-related vision loss.
Omega-3 may help preserve vision
The omega-3 fatty acid in question is docosahexaenoic acid (DHA), which the body is capable of producing in small amounts. However, people must get the necessary amounts of DHA from supplements or foods such as cold water fatty fish (e.g., salmon, tuna, herring). Vegetarian sources of DHA are extracted from seaweed.
The body uses DHA for development of the nervous system and vision during the first six months of life and for healthy brain function during adulthood. DHA also plays a part in heart health, and some research has suggested it may have a role in cancer prevention.
As people age, retina function progressively declines and A2E, a component of the toxin lipofuscin, builds up in the retinal pigment epithelial cells. These events are usually worse in people who have age-related retinal diseases, such as macular degeneration.
At the University of Alberta, a team of investigators under the auspices of Yves Sauve, a researcher in the Faculty of Medicine & Dentistry, conducted studies in mice and discovered that those fed DHA did not accumulate lipofuscin and its compound. Lipofuscin, a brownish pigment left over from the breakdown of damaged blood cells, is also known as the aging pigment.
Sauve noted that this toxin increases twofold as people age. In their lab tests, however, "there was no increase in this toxin whatsoever. This has never been demonstrated before--that supplementing the diet with DHA could make this kind of difference."
According to Sauve, their discovery "could result in a very broad therapeutic use." To that end, the scientists have already initiated another study that involves individuals with age-related macular degeneration, the leading cause of blindness in people older than 50.
In that study, they will explore whether people who have certain genetic markers will respond to DHA in the diet. That work, along with the findings from the current study and future research, will hopefully clarify how this omega-3 can help prevent age-related vision loss.
Dornstauder B et al. Dietary docosahexaenoic acid supplementation prevents age-related functional losses and A2E accumulation in the retina. Investigative Ophthalmology and Visual Sciences 2012 Apr; 53(4): 2256-65
Image: Wikimedia Commons