sunblock - why?

If you're in the sun, skin must be protected. Why? Because the sun gives out harmful rays: Ultra Violet radiation. It doesn't matter that the UK isn't generally a hot country - we still get the rays.


UVA v UVB v UVC?

UVA (alpha) rays are quite a long (solar spectrum-320-400 nanometers) which enables then to penetrate and thus harm our skins more deeply: this is why they are the greatest factor in ageing skin. UVB (beta) rays are shorter (290-320) and are partially absorbed by the Ozone layer. UVC rays are almost wholly absorbed by the Ozone layer - as yet. Good job, as these would be the most harmful rays. As is known, this protective layer is being steadily depleted at certain points of the Earth's atmosphere. If you can't be arsed being environmentally aware for the purposes of the future inhabitants of the planet, do it so you look less haggard in 40 years time.


Ageing and sun exposure

Of the UV light reaching Earth, 90-95% is UVA. Thus it is thought these rays are the main culprits in ageing - they wrought deep tissue damage the direct result of which is premature ageing. They are also involved in the first stages of tanning - their deep action on the skin prompts it to form its protective melanin coat. UVB are the rays which burn us, however these do play a role (along with escaped UVC) in ageing.

While the desire to stay unhaggard is a motivating factor in caring for our skin & staying our of its harmful blast, sustained exposure to its rays can bring about much more serious harm in the form of skin cancers.

The 'good' things we get from sun exposure - freckles, tans are symptomatic of skin damage. Further damage can be seen in skin given sustained sun exposure - loss of elasticity, coarse texture and premature wrinkling. The things we consider 'bad' - burn, peeling skin, redness are the immediate effects of unprotected sun exposure - as the skin forms it protective coat (tan) we think we're safe, but while this may give a small degree of protection, it is essentially a defense mechanism - the skin putting up its arms screaming 'stop!' at the onslaught of harmful rays battering it.

UVB rays cannot harm you through glass, but UVA rays can.

Tanning salons are as bad as sitting in the bright sun, unprotected.

Having darker-toned skin gives you NO added protection from skin damage.


Sun block?

You've to factor in two discrete protection factors - that for UVB (the SPF rating system) and that for UVA (the star rating). The best option is to go for the highest of each: I use SPF40 with 5-star protection. Anything over SPF20 is recommended for us pasty Scots - for daily use. Look for 5-stars if possible in addition to the SPF rating - remember its is UVA rays which do the most damage. The SPF value relates to time spent in the sun - it gives X times (where X is the SPF factor) the length of time in the sub before burning as opposed to unprotected skin. As this rating protects only against UVB rays it is imperative to look for something with the anti-UVA star rating.


Key phrases to look for when buying sunblock

broad-spectrum: a sun protection product which should protect you from the whole UVA and UVB spectrum

filters or blocks?:

An UV filter ABSORBS rays whereas an UV block forms a layer over the skin that physically scatters and reflects UV rays. Filters are called 'chemical sunscreens' while blocks are 'physical sunscreens'.

Blocks, physical sunscreens, as they are composed of minerals tend to be heavier. Filters are lighter and are more easily absorbed.