From our earliest childhood, we have all grown to love and appreciate the sun which we associate with warmth and relaxation. Solar deities and sun worship can be found throughout most of recorded history, in various forms. Without sunlight, the existence of life on Earth is not possible. On the other hand, UVR radiation is regarded as representing one of the most important environmental hazards for human skin. In reality, the sun is both our best friend and our worst enemy.
Today it is no secret that the sun has invaluable health benefits. UV light helps to synthesize vitamin D, in the body which is essential for absorbing calcium, keeping our bones healthy, and for protecting against serious chronic diseases later in life such as osteoporosis, Type II diabetes, multiple sclerosis and many common cancers. Direct sunlight also helps us produce serotonin, a neurotransmitter which is associated with happy feelings, this chemical is often lacking in people suffering with anxiety and depression.
The adverse effects of the sun on our skin can take various forms, and so it is worth keeping them in mind in order to maintain a healthy skin.
The acute clinical effect of ultraviolet exposure to the skin involves melanogenesis, i.e. tanning, when our body generates melanin, which is our natural sunscreen, which protects us against harmful UV rays. Too much exposure to skin can cause unwanted hyper pigmentation, age spots and melasma to appear. Sun damage to the skin has a cumulative effect, so even a brief period in the sun adds to a significant total over a lifetime.
UV radiation can be high even on cool and overcast days. This means you can’t rely on clear skies or high temperatures to determine when you need to protect yourself from the sun. This is why a common impact of direct sun exposure on our skin is the typical sunburn; and its effects lead to reddened, irritated and sore skin.
Repeated skin exposure is also the main causes of premature skin aging, as the skin in the sun generates free radicals under the influence mostly of UVA rays. These free radicals damage skin cells by breaking down the collagen and elastin that give skin its youthful appearance; the skin then produces wrinkles and starts sagging prematurely.
Research shows that the more time spent in the sun and repeated sunburn over the years, the greater are the odds of developing actinic keratosis (AK), also known as a solar keratosis. This skin disorder appears in the form of dry, red or brown scaly patches of skin once the skin has been exposed to the sun. Such crusty, scaly growths can be painful but do not represent a danger if properly treated. However, if left untreated, AK can potentially lead to skin cancer.
More than 90 percent of skin cancers are solely caused by over sun exposure. There are the 3 main kinds of skin cancer: Basal skin cancer, Squamous cell carcinoma, and the most serious one, Melanoma, which often appears as a mole, or in the change of appearance in an existing mole on the skin.
UVA rays are also one of the primary causes of sun allergies. They reduce the strength of our body’s immune system, making skin more prone to allergic reactions from the sun. The most common types of allergies are Polymorphus Light Eruption (PLE) and Acne Aestivalis, the latter is caused by a combination of UVA rays and sun creams or sprays, and leads to skin irritation and inflammation.
A balance is required between excessive sun exposure which increases the risk of skin cancer and enough sun exposure to maintain adequate vitamin D levels. Production of vitamin D from exposure of the skin to sunlight is influenced by a number of factors including age, skin colour, latitude, season and time of day, making it difficult to provide advice to the population as a whole. Given the considerable evidence showing UV to be carcinogenic, skin cancer prevention must remain as a high public health priority. For this reason, extended and deliberate sun exposure without any form of sun protection when the UV Index is 3 or above is not recommended, even for those diagnosed with vitamin D deficiency.
As a rule of thumb, each individual exposing is/her skin to the sun should keep in mind the following basic advice:
- Avoid the sun as much as possible, and particularly between 11:00 am and 3:00 pm when the UV index is at its highest.
- Babies and young children should be kept away from all sun exposure, be it direct or reflected,
- While in the sun, it is advised to wear protective clothing, wide-brimmed hats as well as sunglasses,
- The application of a broad spectrum sunscreen minimum SPF 15 should be part of a daily skin protection routine,
- Apply sunscreen 20 minutes before you go outdoors and every two hours afterwards. Sunscreen should never be used to extend the time you spend in the sun.
- Check closely for any skin change in appearance and/or pigmentation, and if in doubt, immediately consult with your physician or usual dermatologist.
A great way to stay healthy and to take great care of your skin is to visit your dermatologist on a regular basis for check-ups and treatments.