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279 points petethomas | 1 comments | | HN request time: 0s | source
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namuol ◴[] No.45305025[source]
> A study published last year, for instance, examined medical data from 360,000 light-skinned Brits and found that greater exposure to UV radiation—either from living in Britain’s sunnier southern bits rather than the darker north, or from regularly using sunbeds—was correlated with either a 12% and 15% lower risk, respectively, of dying, even when the raised risk of skin cancer was taken into account.

Emphasis on “may” - this is hardly a gold standard study. Living in sunnier/warmer climates as a proxy for UV exposure as opposed to lifestyle differences afforded by such a climate, regional culture differences, etc. makes all of this very dubious to me.

I’m going to keep wearing my sunscreen most of the time when I need to be in direct sun, and continue regular screening for skin cancer.

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lurking_swe ◴[] No.45305992[source]
time of day and UV index is the most important thing, right? That is how you can accurately assess the “risk” of being exposed in direct sunlight.

Example: would you put on sunscreen when playing volleyball at the beach at 4:30pm, if the UV index at that time is 2 (UVI scale)? That seems completely unnecessary imo. And many people are vitamin d deficient anyway, so the minor sun exposure would certainly do more good.

If it’s around mid-day and/or the UV index is higher, say 4+, then i 100% agree with you that it’s prudent to apply sunscreen.

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jnsie ◴[] No.45306244[source]
How reliable are UV indexes? Genuine question. The iOS weather app is far from 100% reliable and I wonder the margin of error regarding the UV index number it provides.
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ComputerGuru ◴[] No.45307635[source]
I am in a unique position to confirm that they are a load of bunk. I have solar urticaria and develop hives in response to UV exposure, directly proportional to how much UV is getting through. I’ve developed hives in minutes while the UV index was supposedly only 4 and gone for relatively too long without erupting in hives the next day even when the UV index was supposedly 10.
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1. lurking_swe ◴[] No.45308438{3}[source]
i hate to be that person that quotes chatgpt, but this seems VERY relevant to your complaint:

“Solar urticaria is a rare condition where the skin reacts to specific wavelengths of light rather than the overall UV intensity. The UV index is a general measure of the total amount of erythema-causing UV radiation (mainly UVB) that can cause sunburn in the average person.

But in solar urticaria, the trigger might be UVA, visible light, or even a narrow band of wavelengths — and the UV index doesn’t capture that nuance.

So it’s not that the forecast is wrong — just that the UV index isn’t designed to reflect the sensitivity profile of solar urticaria.”

In other words, you’re (literally) a special case. :)