Eyes | May 3, 2017 | Author: Naturopath
Macular Degeneration (MD) refers to a group of degenerative diseases that affect the retina— causing progressive loss of vision in the centre of the visual field. This loss of vision affects the ability to see fine detail, drive, read, recognise faces and perform other daily activities. Macular degeneration is the leading cause of irreversible blindness, affecting one third of adults over 75 years of age. Oxidative damage due to smoking and excessive sun exposure as well as poor diet are the main risk factors associated with this condition. Although there is no cure for MD, there are many treatment options that can be used to slow its progression.
For people wanting to prevent it from occurring in the first place, particularly if you have a strong family history of MD, there are many preventative modifications that you can make in your diet and lifestyle that have been proven to reduce your risk.
Common signs and symptoms associated with MD include:
MD begins in the Retinal Pigment Epithelium (RPE), a layer of cells underneath the retina. It is responsible for providing oxygen, sugar and other nutrients to the retina and moving waste products down to ‘the choroid’.
In MD, these waste products, known as ‘drusen’, accumulates between the layers of the RPE and promotes leakage of the fluid behind the fovea (a pit positioned within the centre of the macula), resulting in death of cone cells (photoreceptors) within the fovea.
This loss of cone cells causes the total loss of or blurred central vision.
There are two types of macular degeneration:
Dry macular degeneration is the more common but milder form of MD characterised by the thinning of the retina and drusen deposition.
Wet macular degeneration is a more series form of MD with faster progression of the condition. It is characterised by drusen deposition and haemorrhaging of vessels under the retinal layer, which causes retinal cells to die.
Follow these three steps to reduce your risk of developing MD. In epidemiological studies a healthy diet, coupled with the absence of smoking and physical activity were associated with a reduced occurrence of early or advanced MD. In one study, women aged between 50-74 years of age who followed these same recommendations had threefold lower odds for early MD compared to women who displayed unhealthy lifestyles.
Cigarette smoking has been shown to be one of the major modifiable risk factors for MD, almost doubling the risk of its development while also promoting the progression of the disease. These accelerated changes are likely due to the toxic compounds, many of which have been shown to induce oxidative stress and decrease free radical scavengers. But most importantly, if cigarette smoking is given up early enough, it can to some extent reverse the damage it has caused.
The adoption of a healthy dietary pattern such as the Mediterranean diet is associated with a lower risk of MD.
This diet is rich in vegetables, legumes, cereals, fruits, seeds and nuts, thereby providing high amounts of antioxidant compounds. Dairy products and poultry are consumed in low to moderate amounts with low amounts of red and processed meats. Wine is consumed during meals in low to moderate amounts. It is high in fatty fish such as salmon, trout, sardines and mackerel, rich in omega-3 fatty acids and olive oil as a source of monounsaturated fat.
The Alienor study, performed on elderly residents in France found that the regular use of olive oil was significantly associated with a decreased risk of late MD.
Specific antioxidants have been found to play a significant role in eye health. The carotenoids lutein and zeaxanthin are not synthesised by humans and are found in dark leafy greens such as spinach, kale, watercress and collards, broccoli and pumpkin. Foods rich in beta-carotene, flavonoids and vitamins C and E are also important and are found in a variety of vegetables, fruits, nuts, seeds and cereals. Zinc is vital for healthy eye function and is found in cereals, nuts, seeds, meat and seafood. Dark berries such as blueberries, bilberry, blackberries and dark cherries may also lower the risk.
For people who already have MD, taking a supplement with these antioxidants as well as omega-3 have been found to reduce the progression of the condition.
One to two hours of low-intensity physical activity each day, preferably outside, is associated with a decreased risk of developing MD. Insufficient physical activity increases the build-up of metabolic wastes and contributes to an increase in inflammatory events. On the other hand, exercise can upregulate the enzymatic systems related to antioxidant protection, reducing oxidative stress. Being outdoors can also contribute to a better vitamin D status, also associated with a lower risk of MD. Try walking, swimming, cycling or any activity where your moving rather than sitting.
Other ways to reduce your risk include maintaining a healthy weight and making sure your blood pressure and cholesterol readings are within normal range. Wearing sunglasses can also protect your eyes from the damaging effects of too much sunlight.
Yu SS, et al. Links between the brain and retina: the effects of cigarette smoking-induced age-related changes in Alzheimer’s disease and macular degeneration. Front Neurol. 2016 Jul 27;7:119
Cougnard-Grégoire A, et al. Olive oil consumption and age-related macular degeneration: the alienor study. PLoS One. 2016 Jul 28;11(7):e0160240
Carneiro Â, et al. Nutritional and lifestyle interventions for age-related macular degeneration: a review. Oxid Med Cell Longey. 2017;2017:6469138