I’m confused about the benefits of sunscreen. I thought it was important to wear it all the time – even in winter – to prevent sun damage, but I’ve read that we need some sun (without sunscreen) for vitamin D. Sunscreens also seem to contain chemicals that are bad for long-term health?
The GP Naomi Potter
Levels of UV radiation are low in Britain during winter, so at this time of year sunscreen should not be necessary unless you are outside for prolonged periods. The evidence regarding long-term harm from sunscreen is unclear, but the evidence for long-term harm (premature ageing, skin cancer) from too much sun is well known. We need some sun for vitamin-D synthesis, but most people meet their requirements through their outdoor activities.
The Facialist Linda Meredith
Since the introduction of SPF creams, skin cancer has increased, mainly because no one seems aware that for total protection creams must be reapplied every two hours. I don’t think you should use them all year in Britain, as most have components that may break down to form damaging free radicals. Sunscreen is obviously a must in direct sunlight, to prevent burning, but remove it completely at the end of the day, and look for para-aminobenzoic-acid-free formulae.
The Dermatologist Ross Perry
Sunlight accounts for 90 per cent of our vitamin-D production, and we are seeing more patients with deficiencies due to lifestyles and confusion about how to use sunblock. Exposing your arms and face to the sun for 15 minutes once or twice a week in summer is enough to help with vitamin-D production and won’t mean you age quicker. Micronized-titanium-dioxide- and micronized-zinc-oxide-based creams that sit on the skin and block rays are best.
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