There are essentially two types of skin ageing, namely intrinsic or chronological-ageing and photo-ageing of the skin. The easiest way to differentiate between these two types of skin ageing is to have a good look at yourself in a full length mirror when you get out of the shower.
The skin on your bottom is intrinsic or chronological-aged and the skin on your face, neck, arms and the back of your hands is photo-aged. In other words, the skin on one’s buttocks has essentially been protected from the sun over the years and conversely, the face, neck, arms and back of your hands have been exposed to the ravages of ultra-violet radiation and other environmental factors.
The degree of photo-ageing will depend upon one’s skin type and the accumulative dosage of ultra-violet radiation one has accumulated over a whole lifetime. I usually explain it to my patients by saying that when you are born, it is almost as though you have a meter on your forehead that registers: 000 and every time you are exposed to the sun, the meter ticks over. Most people will get approximately two-thirds of their total sun exposure before the age of 20! Photo-ageing can take a long time to become apparent because of this accumulative effect. Often skin laxity is one of the first signs of photo-ageing due to the collagen and elastin becoming damaged by the UV rays – it becomes loose and causes wrinkles, skin tone becomes dull and of course gravity also takes its toll when jowls and sagging appear.
There are numerous other signs of chronic sun damage and these include darker sun freckles, paler areas, dryness of the skin, dilated capillaries, venous lakes on the lower lip and easy bruising especially on the forearms – this we call purpura. With chronic sun damage, one often gets milia which are tiny little whiteheads and sebaceous gland hyperplasia. Solar Keratoses (i.e. pre-malignant) are often red, scaly areas, commonly seen on sun-exposed areas and usually in patients with a fair skin. A certain percentage of these solar keratoses can develop into squamous cell carcinoma so it is generally recommended that the solar keratoses be treated. If there are just a few lesions, then these can be treated with cryotherapy or liquid nitrogen. Other treatments would include Efudix ointment and Aldara cream.
While you cannot stop the intrinsic or chronological-ageing process, you can prevent a certain amount of photo-ageing by avoiding the sun during the hottest part of the day, always wearing a sunscreen, even on overcast days, wearing a protective hat and clothing, avoiding smoking and tanning beds. Treatment for photo-aged skins includes the use of anti-oxidants, anti-ageing moisturisers with a sunblock during the day and the addition of anti-ageing serums at night.
Leading on from the subject of skin ageing, I am planning to discuss various topics in future blogs which would include the myths and facts of sunscreens, anti-ageing creams, Botox, chemical peels and the various lasers used for photo-ageing.
Dr Ian Webster