Which sunscreen should I use?

Thinking about a late summer escape? Then you will want to be stocked up with the right sunscreen. The vast range of sunscreens are available in pharmacies or supermarkets can be bewildering. Understanding a little bit about how they work and what they do will help you choose a product that’s suitable. The purpose of sunscreen is to block Ultraviolet (UV) radiation. UVB causes tanning, burning and skin cancer. UVA causes collagen damage, premature ageing and skin cancer. Did you know that UV Radiatio, like tobacco, is now rated a Group 1 Carcinogen – that is, a hazard that causes cancer in humans?

Ensure your suncreen has UVA and UVB cover

Sunscreens carry an SPF Rating. This is derived from laboratory studies and reflects how good the sunscreen is at blocking UVB light. A sunscreen with an SPF of 15 blocks 93% of UVB light. SPF 30 sunscreens block 96% of UV light and SPF 50 block 98% of light. So double the SPF does not block double the amount of light.  There is no internationally recognised UVA rating system though in the UK the Boots Star Rating is used by many sunscreen manufacturers. A one star offers minimum protection against UVA while a five star rated product provides maximal UVA protection. You should ensure your suncreen is broad-spectrum, that is, it protects against UVB and UVB

Physical or chemical?

Some products contain physical UV blockers such as titanium dioxide and zinc oxide. These reflect and absorb the light. They are less likely to cause allergic reactions but more likely to be opaque on the skin. Chemical sunscreens contain molecules that absorb light such as octyl methoxycinnamate (OMC) and methylbenzylidene camphor, prime UVB filters; and butyl methoxycinnamate, a prime UVA filter. Products designed for children often contain physical blockers as these are thought to cause less irritation.

Cream, lotion or spray?

Sprays are useful to cover large areas quickly or hair bearing areas. The choice is based purely on personal preference but it is important to appreciate that thinner preparions such as lotions and sprays are likely to be sweated and wiped off sooner and will need more frequent reapplication.

Apply sunscreen 20 minutes before going out and then every 2 hrs

Forgetting to do this is the main reason that sunscreens fail. Apply sunscreen 20 minutes before you go outside and every 2 hrs thereafter – whether or not the label tells you to do this. This is because sunscreens degrade, and get sweated, wiped or washed off. Its best to reapply sunscreen after swimming as well. So called ‘once-a-day’ sunscreens and ‘waterproof’ sunscreens are of dubious value and these products need to be reapplied as well

And finally…..apply enough else it won’t work!

A good layer of sunscreen is needed for it to work – for the average-sized adult, this means  half a teaspoon  (about 3 ml) to each arm and the face/neck (including ears), and just over one teaspoon (about 6 ml) to each leg, front of body and back of body. This means that one full body application requires 35 ml of sunscreen. Children need a proportionately smaller amount.

The Midland Skin Institute is a private dermatology service based in Birmingham that specialises in skin disorders and offers a comprehensive skin cancer service from screening to management. More information can be found at www.midlandskin.co.uk.