Re: Do sunscreens protect equally against UV, regardless of SPF


Oops, I messed up and didn't finish posting all the info. so here is
the rest:

Why bother to block UVA

It turns out that long UVA can cause the skin to age and is likely
involved in the more serious skin cancers such as melanoma. Wrinkles,
uneven pigmentation, sagging and age spots associated with old age are
mostly due to sun exposure and could be prevented with sun avoidance,
proper clothing and a good sunscreen that blocks long UVA. It has been
suggested that sunscreens that block only UVB and some short UVA might
be doing damage because they allow one to be exposed to larger amounts
of long UVA than the person otherwise would have been. This remains a
controversial point, but few will argue that long UVA should be
blocked.

Choosing a Sunscreen

As mentioned above, there is no label requirement for long UVA. The
American Academy of Dermatology has made recommendations to the FDA
regarding this, yet no law has been enacted. At last notice from the
FDA, it looks as though no long UVA labeling will be required until at
least 2005. What is the consumer supposed to do until then?

The only answer is to read the label and question your sunscreen
manufacturer. There are a number of ingredients that block long UVA
including zinc oxide and avobenzone, otherwise known as Parsol 1789.
Although avobenzone blocks long UVA, it has some issues that limit its
usefulness. Avobenzone is photo-unstable, meaning that it breaks down
in the sun and there is clinical evidence that it can cause allergic
reactions.

Zinc oxide is very photo-stable and is not known to cause any allergic
reactions. Early versions of zinc oxide were white and pasty. Newer
versions are completely transparent and very elegant.

Whatever sunscreen you chose, make sure it blocks UVA and ask the
manufacturer about what tests they conduct to insure this - its your
skin and you need to take control of how you treat it.

.

Relevant Pages

  • Re: Do sunscreens protect equally against UV, regardless of SPF
    ... The sun emits a number of different types of radiation, ... UVR is divided into three types: UVA, UVB ... Sunscreens do not provide total ... UVA is divided into two parts, ...
    (alt.fashion)
  • Re: Topical Sun Protectives
    ... Some protection is better than none. ... does not provide much UVA protection. ... as well as a few other chemical UVA filters on the horizon. ... The sunscreens most effective in blocking and/or reflecting UVA ...
    (sci.med)
  • Re: Topical Sun Protectives
    ... Some protection is better than none. ... does not provide much UVA protection. ... as well as a few other chemical UVA filters on the horizon. ... The sunscreens most effective in blocking and/or reflecting UVA ...
    (sci.med.nutrition)