Prevent blindness, ageing with sunglasses

Wearing sunglasses does not only make you look good and in control of the situations around, it ensures that your eyes are protected from cataract and ageing, reports Sade Oguntola.

Just about all fashion-loving people wear some form of big glasses. They surely have their reasons for it if they are asked. Though the most obvious benefit is that they make you look outstanding, but this is one fashion accessory with many health benefits. They protect eyes from the UV radiation, an invisible form of energy that takes the form of radiation, which can damage eyes if they are overexposed. They also ensure fewer wrinkles when you are older.

For some certain groups of individuals, this is one way to cope with some side effects of some medications. Some medications such as that to treat psoriasis and malaria can cause people to experience photosensitivity. A good example of such drugs that heighten sensitivity to sunlight and causing increased discomfort if sunglasses are not in place is chloroquine.

Dr. Gboyega Ajayi, an eye specialist at Ojulowo Eye Clinic, Ibadan, said the ordinary light from sunlight consists of rays with many wavelengths, some visible and some invisible. While we use those that are visible to see, the invisible rays, which include ultra-violet rays, that cannot be seen are, however, dangerous to the eyes.

These rays, called UVA and UVB, can cause irreparable damage to your retina and corneas, one reason people are cautioned on staring directly to the sun.

Meanwhile, such disorders as cataracts, macular degeneration, and even skin cancer around the eyes can be signs of sun damage and can be prevented in part by the use of sunglasses. Although, no one truly knows what causes cataracts, studies have shown links between this condition and increased exposure to ultraviolet light.

Despite the fact that in countries like Nigeria it could be very sunny, Dr. Ajayi explained that the environment is not very reflective and so, the rays of the sun do not bounce back to the eye from the surfaces around.

Dr. Ajayi declared: “UV rays can cause certain damages to the conjunctiva and cornea just as a disease called pterygium can cause increase exposure of the eye to higher amounts of UV light, especially when there is lot of dust. This is rampant in some areas in Nigeria. Pterygium is hardly seen in temperate climates and if it is seen at all, it will be seen in immigrants to the area or in those that have spent a number of years in the tropics. Pterygium is a raised, wedge-shaped growth of the conjunctiva.  It is most common among those who live in tropical climates or spend a lot of time in the sun. Its symptoms may include irritation, redness, and tearing. 

He explained that pterygium can cause visual impairment such as astigmatism with time, if it grows over the central cornea, adding that with more UV rays now entering the eye, it can become red, uncomfortable, itchy and so on. 

Since pterygium is most commonly caused by sun exposure, protecting the eyes from sun, dust and wind with sunglasses is recommended. 

Though the eyes of people in tropical areas are not as exposed to dangers from UV rays as those in temperate countries because there is lesser reflective surfaces for the rays of the sun, Dr. Ajayi, however, said anybody wearing a pair of sunglasses must ensure that the type he or she is wearing has UV filters.

“Ordinary glasses may be protective against dusts entering the eyes but the other side of the coin is that in areas with lots of UV rays reflecting surfaces, like the sea shore, if you must wear any, it must be one with a UV filter. You can only have a false sense of protection wearing ordinary glasses. You will still be absorbing more UV rays than you would without the glasses because it cuts down some other rays and allows UV to pass into the eyes unhindered.

“It is the same reason that people are asked not to look directly at the sun so as not to become blind. The UV rays from the sun can burn the macula, which is the sensitive part of the innermost coating of the eye used for seeing. Because the burn most times is irreversible, such a person may go blind for life,” he said.

While assuring that sunglasses with UV rays filter always have it indicated on it, he emphasised that wearing any sunglasses at night, when it is dark or when there is no sun is unnecessary. He said “such a habit of wearing it in the dark or when there is no sun would be of a bigger disadvantage because it will reduce the amount of light into the eyes and so, such a person will not see well. Such, when walking, may miss his steps and have a fall.”

He also assured that wearing sunglasses is okay to protect the eyes from too much light after cataract surgery, a covering for a cosmetic blemish, or when wanting to prevent people from being able to read the expression on their faces or follow the direction of their gaze.

One use for sunglasses has only recently been discovered. The next time you are flying overseas and want to avoid the taxing effects of jet lag, try to put on a pair of sunglasses. Scientists discovered that sunglasses help fool the body through the use of light. Your biological clock (which-as it turns out-is a real thing) consists of about 20,000 nerve cells that respond differently to light and darkness. By wearing sunglasses for a certain period of time during a long trip, you can lessen the effects of jet lag.

Sunglasses can offer wind resistance to protect your eyes from drying out. Whether riding in an open vehicle or on motorcycle, wearing the proper sunglasses can keep your eyes from the painful wind effects. When wind hits the eye, it dries it out and causes burning, itching, and irritation.

Similarly, Dr. Ayotunde Ajayeoba, a consultant in the Department of Ophthalmology, University College Hospital (UCH), Ibadan, said wearing sunglasses can help prevent a medical problem called solar retinopathy (maculopathy) which occurs as a result of too much sun damaging the back of the eye.

He assured that sunglasses, whether with tinted or photo chromic lenses, can help filter off some of the dangerous rays of light from the sun which can easily damage the eye just as wearing it tends to reduce your tendency to squint due to bright light. Thus, it helps reduce the appearance of crow’s feet by allowing your facial muscles to remain relaxed.

Even if you need to wear it when driving, recommendations by the UK’s Eye Care Trust is that :

Choose a design with a thin frame and arms so that it will not obscure your peripheral vision.

Wear those with lighter tint.

Choose polarising filters if possible as they specifically cut the kind of reflected light created by the windscreen of the car in front of you, and reflections cast up from the road by water or debris.

So, when next you want to buy any pair of sunglasses, just about any face shape can help protect your eyes and still give you the cool look you desire. While those with round faces may want to opt for a smaller, more angular style than the traditionally round lens style of big sunglasses, oval, square and heart-shaped faces will look elegant in oversized black lenses and frames. For a bit of fun, you can also try other colours like blue frames with navy blue lenses. White frames with black lenses look amazing and offer a new twist on a popular style too.