3 Comments
User's avatar
Steve's avatar

What keeps confusing me is the claim that after x amount of time you receive damage.

What I'd like to know is, what are the stages of damage you receive from sun exposure.

Because the way this is worded (not just by you but in any related literature) it always sounds as if you do not receive damage until those 30 minutes when you turn red.

Is that actually the case?

Do you only receive damage once you turn red?

Or do you receive damage on your way to turning red already?

And if so, say you turn red after 30 minutes under whatever conditions, do you receive 50% of that damage after 15 minutes, meaning is the damage occuring linearly or is it exponential and not that bad until you actually turn red?

Expand full comment
Fabio's avatar

Hi Steve! I was wondering the same thing myself!

It'd be amazing if it was like that, but I'm afraid it's not, I guess you still get a little bit of damage even before getting the erythema, maybe a little less, I don't know.

Surely they say that if you get a lot of sunburns you have more chances of getting skin cancer, I think this is because of the erythema, so basically the fact that you damaged your skin a lot in a short period of time and also the total amount of photones/power (dose) that you got to get that sunburn.

The thing is that you can get the same dose by staying out in the sun just 30 minutes a day with UVI 1, the difference is that you spread it over a longer period (a lot of days) and therefore you don't get any erythema/sunburn and yet the dose you received is the same.

This could mean that if you don't get the erythema, you haven't stayed long enough to cause a "deeper" damage and your molecules can sort of recover from it without having long term damage.

This is just my assumption so I'm not sure, what do you think? Maybe Richard has a better answer.

Regardless of the assumptions above, by using 1MED as the maximum unprotected daily dose, you are making sure that you don't stay a lot in the sun anyway, which in turn results in less damage and lower probability of getting skin cancer.

Expand full comment
Chelsea Langman's avatar

Agree!!That’s why everyone should use the UVNZ app, highly promoted at Skin Aware, even on our sunscreen stations https://skinaware.co.nz/get-proactive/

Expand full comment