Shocking Proof of How the Sun Ages You

This man is 69 years old, but half of his face looks much, much older than that. He was a trucker and, for 28 years, his face received much more sunlight on the left side, resulting on premature ageing.
We all knew that being exposed to the sun makes you age prematurely, but seeing the dramatic difference in a single face is just stunning.

His condition is called unilateral dermatoheliosis, from the Greek dermis and helios, skin and sun. It’s also called photoaging, and it results from chronic exposure to the Sun’s UVA and UVB rays. In his case it only affected him on the left side because of his work. As he drove, he received much many hours of sunlight through the left window of his vehicle.
The case was discovered and studied by Jennifer R.S. Gordon and Joaquin C. Brieva, dermatologists at Northwestern University, and published in the New England Journal of Medicine:
A 69-year-old man presented with a 25-year history of gradual, asymptomatic thickening and wrinkling of the skin on the left side of his face. The physical examination showed hyperkeratosis with accentuated ridging, multiple open comedones, and areas of nodular elastosis. Histopathological analysis showed an accumulation of elastolytic material in the dermis and the formation of milia within the vellus hair follicles. Findings were consistent with the Favre-Racouchot syndrome of photodamaged skin, known as dermatoheliosis.
The patient reported that he had driven a delivery truck for 28 years. Ultraviolet A (UVA) rays transmit through window glass, penetrating the epidermis and upper layers of dermis. Chronic UVA exposure can result in thickening of the epidermis and stratum corneum, as well as destruction of elastic fibres. This photoaging effect of UVA is contrasted with photocarcinogenesis.
Since UVB and UVA can cause DNA mutations leading to skin cancer, the doctors recommended their patient to use sun protection and topical retinoids, as well as periodic monitoring for the apparition of skin cancer.
This is a perfect reminder of the negative effects of excessive sun-tanning. If the risk of skin cancer is not enough for you, perhaps knowing that the sun will accelerate your ageing by a decade or two will stop you from being careless. Remember, if you are going to be exposed to the sun in any way — even if you are not at the beach— use UVB and UVA protection, for the good of your skin and your eyes.

Source Jesus Diaz- http://www.gizmodo.com.au/2012/06/shocking-proof-of-how-the-sun-ages-you/