With many people just about to embark on their summer holidays I often get asked what is the safe way to get a suntan and if having a base tan does protect against skin cancer. The short answer is the only safe tan is one that comes out of a bottle!
When skin is exposed to ultraviolet radiation a number of reactions occur in the skin. The sunlight stimulates the melanocytes which are the pigment producing cells in the epidermis to produce more melanin. The melanin is packaged in melanosomes which are then transferred to the surrounding keratinocytes which are the epidermis skin cells. This process is a biological mechanism to protect the DNA in the basal cells of the epidermis from further insult from UV radiation from the sun as melanin absorbs UV radiation. It is well known that harsh or chronic UV exposure can cause changes in the genetic information contained in these cells and thus induce an abhorrent line of cells which can turn into a tumour. This is why the incidence of skin cancer is much lower in darker skin compared to pale skin. As well as increasing melanin production in the skin UV radiation also induces inflammatory mediators or cytokines which causes damage to other structures in the skin such as the collagen and elastin which then speeds up the ageing process of the skin. This explains why any degree of skin tanning is therefore inflicting damage to the skin.
So whilst having an increased amount of melanin in the skin due to sun exposure will give some protection to the DNA in the basal cells the skin has already been damaged to obtain this. Protecting the skin from the sun by high sun protection factor sunscreens, protective clothing and behavioural modification such as sitting at the table in the shade rather than in the sun at lunch whilst on holiday is advisable to keep the skin healthy and undamaged. Harsh sun exposure to the degree of sunburn or even worse sunstroke is a known risk factor for melanoma. Therefore trying to remain untanned is the healthiest option for your skin.
There are now very good fake tans which can be applied at home or sprayed on in a salon setting which give a very realistic and cosmetically pleasing appearance. These work by the active ingredients in the applications being absorbed into the top layer of the skin and then oxidising over the next few hours. This does not damage the skin but merely ‘stains’ the skin on a temporary basis. With time the epidermis naturally sheds these stained skin cells and the colour is lost. It is very important to note that using fake tan products, although imparting colour to the skin, do not increase your skin’s protection against the sun. There are some reports that they may have a sun protection factor (SPF) factor of 2 at the very most but this cannot be relied upon.
So, enjoy the summer and the sun but practice safe-sun and protect your skin from the harmful UV rays.
Dr Martin Wade, Dermatologist at The London Skin and Hair Clinic