Re: Reactions to sunblocks

[Guest guest]

May I suggest Neutrogena chemical free 17, you can buy it anywhere. It's

the only thing my derm has recommended by name. One of the pluses is it

doesn't smell. I think this has been put out since the book was published.

I also wear a big brim (3 " ) hat a lot.

Becky

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[Guest guest]

> summer is approaching for many of us (sadly, not those who put

prawns

> on the barbie ). I've not signed it, out of respect for the

sender

I didn't know Barbie was the kind of doll who liked prawns...

> -=-=-=

>

>

> Two questions for general consumption: a number of people on the

list

> talk about not needing sunblock when the day is cloudy. Can someone

> explain that reasoning to me? I'm not aware that UV is inhibited by

> clouds, which (aside from rosacea) is suppose to age skin/increase

> risk for skin cancer. I know that my face is sensitive to the heat

of

> the sun -- heat from anything, actually -- which is a problem when

my

> skin is overtly irritated. But sunscreen/block doesn't protect

> against heat, that requires large-rimmed hats, parumbrellas, and

> other shade-producing objects. (One happy discovery: with my skin

> less reactive these days, I've found it is enjoying the sun during

> this mid-April heat wave -- so much different than last fall, when

my

> skin was at its worst, and the heat from the sun actually hurt my

> face.)

Actually zinc oxide reflects the infared spectrum and to some degree

it therefore reflects heat.

We all need sun protection. We need sun protection under the shade,

in clouds, and wherever we are. To some extent depending on cloud

cover and lattitude, the sun's UVB rays are less intensive. There is

a difference between San Diego and Seattle, for instance. The

galderma web site has a USA wide UV exposure map. UVA is less

variable.

>

> Second, can someone explain why spf is so important in these

> discussions? It only measures UVB, and I though rosaceans were as

> much or more concerned about UVA. Since it only measures UVB, and

> since anything over 15 is already above the 90% percentile, I

> wouldn't think that the difference between spf 30 and spf 60 has

much

> practical meaning for most rosaceans. If there is a concern, why

not

> just reapply a lower spf more frequently, which is the best way to

> insure continual coverage anyway, right?

Spf isn't that important. Spectrum of protection is. If you have at

least spf 15, and it is made of a physical sunblock, one should be

fine. Especially for photosenstive people -- UVA II is implicated in

this phenomenon. This leaves zinc oxide, titanium dioxide, and

parsol, as the premior sunblocks, the only ones that have decent UVA

protection.

However, one should always endeavor to avoid the sun so one won't

need to apply a potentially occlusive and comedogenic sunblock.