Diet and age-related macular degeneration
Diet is important for prevention of age-related macular degeneration (AMD). Genetic and environmental factors such as smoking play a role also. Recent scientific evidence shows what you eat, and which vitamin and dietary supplements you take, determines how well you see in many years time and your retinal macular health.
You can help maintain a healthy retina and good vision, by a proper diet, and by taking appropriate dietary supplements, according to the AREDS findings, published May 2013. The benefits of a diet high in Omega 3 fatty acids may play a role according to a British study in 2009.
Dry and wet AMD
Age-related Macular degeneration (AMD) affects the cells in the layer of tissue called the retina at the back of the eye in the zone called the macula that provides sharp central vision necessary for reading, driving, and recognising faces. AMD is a leading cause of blindness.
Over age 50, small yellow deposits called drusen form in the retina. Drusen are a normal part of ageing. With time, the retina breaks down in areas of the macula where there are large drusen, leaving bare patches of the non-functioning retina, called geographic atrophy (GA). This associate with loss of central vision. Diet and supplements can help influence this development.
AMD can spur the growth of new blood vessels beneath the retina, which leaks blood and fluid, resulting in sudden vision loss. Intra-vitreal eye injections help arrest and improve this.
AREDS –First vision and dietary supplement study
- The original five-year Age-related Eye Disease Study (AREDS) by the National Eye Institute (NEI) in the USA 2001, concluded that daily high doses of vitamins C and E, beta- carotene, and minerals zinc and copper—AREDS formulation—slows the progression of AMD to advanced AMD
- Participants with AMD who took the AREDS formulation were 25% less likely to progress to advanced AMD over the five-year study period, compared with participants who received a placebo.
AREDS 2 said, “no more beta carotene, omega-3 fatty acids do not work, Lutein and Zeaxanthin do some good”.
Lutein and zeaxanthin are carotenoids, plant-derived vitamins that include beta-carotene; in leafy green vegetables. They accumulate in the retina.
Omega-3 Fatty Acids
A 2009 study concluded that the Omega-3 fatty acids in oily fish connect with preventing the onset and slowing the progression of AMD in the elderly. The researchers suggested that people at risk should eat two portions of oily fish per week. This was not born out by the AREDS study which is a more robust study.
Omega 3 fatty acids occur in oily fish: salmon, sardines, mackerel, anchovies and herring
Recommendations about Diet and Vision
- Diet and visual health are importantly interlinked, but genetic factors and smoking also influence.
Dr Jaheed Khan at Clinica London says:
“It is sensible to have a healthy diet in leafy vegetables, stop smoking, and keep taking Vitamin supplements as there is some evidence from AREDS that it helps”.
- A healthy diet high in Lutein and Zeaxanthin is beneficial, along with Vitamins A, C, E and possibly Omega 3 fatty acids.
- Long-term use of AREDS supplements appears safe and protective against advanced AMD
- People over 60 years old should get an eye exam once a year and discuss with their eye care professional whether taking AREDS supplements is appropriate.
Ophthalmologists Jaheed Khan and Professor Michel Michaelides at Clinica London assess the risk of developing AMD by looking for drusen in the retina, determine whether they are small or large, whether there are new blood vessels growing (wet AMD) and the risk of causing visual loss.