The human senses are our bridge to our environment and the eyes, “the window to the soul”, are arguably our most important sense organ. We perceive around 80% of all information through sight and as we age, if other senses such as our taste or smell stop working, it’s the eyes that step up to keep us safe.
This is why the increase of age-related macular degeneration (AMD), the leading cause of irreversible vision loss among elderly people, is so devastating.
AMD affects the central part of the retina called the ‘macula’, which is responsible for our detailed vision. There are two forms of AMD – ‘dry’ and ‘wet’. In wet AMD, abnormal blood vessels grow into the macula. These leak fluid and may bleed into the retinal nerve layer so that it becomes water-logged and unable to function.
Wet AMD can develop very suddenly over a few weeks or months, but can be treated if caught quickly. If left untreated the blood and leakage will permanently damage the retinal nerve cells and eventually produce scarring, which is currently irreversible.
Dry AMD, on the other hand, is a gradual deterioration of the macula as the retinal cells die off and are not renewed. There is currently no treatment for dry AMD.
AMD is a ‘progressive disease’, an odd term as the degenerative effects can be devastating. Over time, a person with AMD may find it difficult or impossible to read, drive or even recognise familiar faces.
The exact cause of AMD is unknown. It’s been linked to smoking, high blood pressure, being overweight and having a family history of the disease and it is believed to affect around 1.5m people in the UK alone.
Figures from the Macular Society suggest that around 600,000 of these are affected by age-related macular degeneration (AMD), while as many as 700,000 are affected by other macular conditions with many more at risk, highlighting the extent of what is a real public health issue.
But help is at hand. According to recent research, as we age, key to good eye health and good vision is to ensure we are getting enough carotenoids in our diet.
Carotenoids are naturally occurring pigments that give fruits and vegetables their vibrant red, orange, yellow and green colours. Three carotenoids — lutein, zeaxanthin and meso-zeaxanthin — form the pigment in the macula that protects the millions of photoreceptor cells located in this small region of the central retina.
In particular, the antioxidant and anti-inflammatory properties of these macular pigments reduce oxidative stress on the retina caused by high-energy blue light, which is believed to contribute to the development of macular degeneration.
In response to the growing AMD problem and based on knowledge of macular carotenoids, two large clinical trials, referred to as Age-Related Eye Disease Studies 1 and 2 (AREDS1 and AREDS2), focused on the effects of increased carotenoid ingestion on good eye health.
AREDS1, completed in 2001, initially revealed that daily supplements with a formula rich in lutein and zeaxanthin reduced the risk in subjects with AMD of their macular degeneration progressing to an advanced stage by up to 25 percent.
Based on the positive outcome of this original AREDS study, in 2006 AREDS2 took the research further to see if the supplement used in the initial AREDS trial could be improved and provide added eye benefits.
The outcomes revealed that participants taking the modified AREDS formula with added lutein and zeaxanthin had a 10 to 25 per cent reduction in the risk of AMD progression.
Though there is currently no cure for age-related macular degeneration (AMD), there are a number of things one can do to reduce the risk of getting the disease and experiencing AMD-related vision loss.
Lifestyle changes including exercise and not smoking help while diets rich in green, leafy vegetables such as kale, spinach and chard that have a good source of lutein and zeaxanthin have a lower risk of developing AMD. But because the human body cannot make lutein or zeaxanthin and they have to be ingested in high levels to make a difference, supplementing them in your diet will have a greater impact on reducing the risk of developing advanced AMD.
While many supplements contain two of the three vital ingredients for eye health (Lutein and Zeaxanthin), most exclude the most important which is Meso-Zeaxanthin. There are a lot of vitamins and foods and other products out there that may support the health of your vision.