Despite all the warnings about the dangers of the sun, many of us are still not sun-savvy.
“Over-exposure to UV rays can lead to premature skin-ageing and brown pigmentation and, at worst, skin cancer,” says Dr Richard Barlow, consultant dermatologist at St Thomas’s and the Lister hospitals. “Ultraviolet (UV) radiation is part of the light which reaches the earth from the sun. UVA rays are strongest in summer and penetrate more deeply, causing more photo-ageing effects than UVB rays which are the ones responsible for sunburn. UVA exposure generates free radicals which in turn damages DNA and in some cases can predispose the cells to skin cancers.UVB is largely filtered out by the Earth’s atmosphere in the northern winters and is only strong when the sun is overhead. UVB also causes some damage to collagen but at a slower rate than UVA.”
Dr Robert Sarkany, consultant dermatologist and head of photo-dermatology at St John’s Institute of Dermatology, based at St Thomas’s Hospital, also cautions against excessive exposure, especially if you have fair skin or have a family history of skin cancer: “Sunburn is particularly damaging to the skin, and a tan, which is the body’s response to UVB exposure, is still harmful to the skin. Sunburn and, to a lesser extent long-term tanning, increases your chance of skin cancer.”
Dr Sarkany also suggests “applying broad-spectrum SPF 25-40 thickly during the months of April-October”.
But such advice is being called into question by the latest research taking place around the world, including the UK, the US and Israel.This suggests that there are health risks associated with spending too little time in the sun or consistently slathering skin in very high SPF sunscreens because of fears over skin cancer.
This research is a reminder that the Vitamin D provided by sunlight is an important and vital product of moderate sun exposure.
Dr Barlow says this potential deficiency should be kept in mind by parents who “zealously protect their children” from any kind of UV exposure.
“Ten or 15 minutes per day of summer sunshine is, therefore, a good idea,” he maintains.