Sun exposure: how much is too much

Skin has immense capability to repair from sun damage. And by sun damage - I mean damage at DNA level. Its a complex mechanism but an important one.

In Perth, UV is more than 3 almost every day of the year at some point during the day. And when UV is high, even small duration of sun exposure (eg hanging your washing, collecting your mail) is enough to start the process of DNA damage. Amount of DNA damage is proportional to the duration of exposure.

Body tries to repair the DNA damage and it manifests as:

> increased tan in the skin

> redness

> blistering

Half life of DNA repair is 20-30 hrs (in other words- it will take take about 20-30 hrs to repair about half of the damaged DNA)

Sometimes, these repair mechanisms fail resulting in "mutations" in DNA. Multiple mutations over a long period of time can result in skin cancers.

So remember: Slip, Slop, Slap, Seek and Slide