Healthy eyes: Exercise protects against macular degeneration
Exercise is central to human health: among other things, the heart and circulation, metabolism, skeleton and psyche benefit.
What is less well known is that people who are regularly physically active also do something for their eye health: The risk of developing age-related macular degeneration (AMD) is then significantly lower.
This condition is one of the most common eye diseases in Western nations and is also the most common cause of severe vision loss or blindness.
Metabolic deposits in the eye
The disease usually develops insidiously and often goes unnoticed for many years. In this case, the function of the outermost layer of the retina, the pigment epithelium, continues to decline. This cell layer has the main task of breaking down harmful metabolic products of the photoreceptors.
If this process is disrupted, deposits initially form in or under the retina. Later, the light-sensitive photoreceptors perish. This applies in particular to the central area of the retina – the so-called macula. In this area of the retina lies the place of sharpest vision. And that’s exactly where the eyesight continues to decline.
High blood pressure increases the risk
The risk of age-related macular degeneration increases progressively from the age of about 50. In addition to older age, smoking is considered the most important risk factor. But high blood pressure also increases the risk of AMD. “As a rule of thumb, what is bad for vascular health in the rest of the body also damages the eyes,” says Prof. Frank Holz, Director of the University Eye Clinic Bonn and Chairman of the Eye Foundation.
A direct connection between cardiovascular diseases and AMD is difficult to prove. However, the parallels are so striking that many physicians consider common disease mechanisms to be likely.
Heart protection is also eye protection
“Physical activity has a direct effect on some important parameters that influence both cardiovascular and AMD risk,” explains Holz. In addition to body weight and blood pressure, these include blood sugar regulation and blood lipid levels. Exercise could also activate antioxidant enzymes that also protect the macula from aggressive molecules such as oxygen radicals.
Just walking is not enough
However, a little walking is not enough: This is shown by a German-Dutch evaluation of various studies (meta-analysis) on the topic with a total of more than 14,500 older participants. It found that the risk of AMD is increased for people who exercise little. Specifically, it was 19 percent higher than for people who were highly physically active. The researchers rated intensive exercise, lifting loads and strenuous gardening as high physical activity.
The effect of moderate physical activity cannot be derived from the data. The reason: The overview study included data from various studies that related to different activity criteria. “An exact dose-benefit effect cannot be derived from this,” explains study lead author Dr. Matthias Mauschitz from the University Hospital Bonn when asked by netDoktor.
Sport protects against early onset of the disease
The correlation was most evident in the youngest subjects, who were 61 years old on average: Here, less physically active people were 74 percent more likely to develop AMD than intensively active subjects.
“The message for practice is clear,” says Holz: “Even if AMD is a typical disease of old age, sports or other physical activities should be started in middle age at the latest.”
Then prevention is most effective. Significantly older people are often simply no longer able to re-engage in more intensive physical activity.
In the UAE
Age-related macular degeneration (AMD) is a leading cause of vision loss among individuals aged 50 and older. In the United Arab Emirates (UAE), several specialized eye care centers offer comprehensive services for the diagnosis and management of AMD.