• YarrMatey@lemmy.dbzer0.com
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    11 days ago

    Clothing that is UPF 50 can provide protection but unless your wardrobe is filled with these specialized clothing you won’t get the same protection. For instance, a white T-shirt provides only moderate sun protection, with a UPF of about 7. When that T-shirt gets wet, it provides a UPF of only 3. A dark, long-sleeved denim shirt can provide a UPF of about 1,700; in essence, complete sun protection. (https://www.skincancer.org/skin-cancer-prevention/sun-protection/sun-protective-clothing/)

    It’s recommended to use both sunscreen and sun protective clothing by just about every skin cancer authority (https://www.cancer.org.au/cancer-information/causes-and-prevention/sun-safety/preventing-skin-cancer). I have no idea what data you are referring to that sunscreen is not a good thing, I suspect exposure to fear mongering from the “natural” anti-science crowd. Let me guess, you think sunscreen is a hormonal disruptor even though you would need to use oxybenzone (the “worst” one) sunscreen continuously for 277 years to get the equivalent amount to cause a noticeable hormonal effect - so even oxybenzone is considered safe. Or you think “nano” sunscreen is bad even though the studies so far have found that the nanoparticles don’t get very far into the skin (only to the dead layers of the stratum corneum). It’s possible that nanoparticles will penetrate further if you apply them on broken skin, but they’re currently considered safe.

    Physical vs chemical sunscreens is a debate with a lot of misinformation and fear mongering because people will drink water while not registering water is a filthy cHeMiCaL (half joking). You should be much more concerned where you buy your sunscreen because the US has shitty standards for UVA protection while the other countries have much better UVA systems and standards. I can’t even begin to debunk this but here we go:

    https://labmuffin.com/chemical-vs-physical-sunscreens-the-science-with-video/

    Physical and Chemical work the same

    Physical sunscreen ingredients (more correctly known as inorganic sunscreen ingredients) are zinc oxide and titanium dioxide.

    Chemical sunscreen ingredients (more correctly known as organic sunscreen ingredients) are everything else.

    The reason organic (carbon-based) and inorganic (not carbon-based) is a better classification than chemical/physical is that there’s overlap between how they work. Both types work by absorbing UV and turning it into heat. Inorganic sunscreens also scatter and reflect about 5-10% of the incoming UV, as do some particulate organic sunscreens like Tinosorb M, so really they should be classified as both chemical and physical.

    Natural things aren’t better than synthetic, man-made things

    The amount of heat produced from UV by sunscreen is really, imperceptibly tiny. There’s also only a 5% difference in the heat produced by the two types of sunscreens, since physical sunscreens also absorb about 95% of the UV they protect you from.

    Even if they were – physical sunscreens aren’t even natural. They’re processed to get rid of toxic contaminants, and often need to be coated in synthetic chemicals to stop them from being photocatalytic, and prevent them from clumping up and causing patchy protection.

    https://www.kindofstephen.com/physical-vs-chemical-sunscreens-myths/

    Even more detailed explanation

    Chemicals are physical – they have a mass and take up space. On the other end, the “physical” sunscreens titanium dioxide and zinc oxide are chemicals, you can find the elements titanium and zinc on the periodic table.

    In marketing, organic is a label that describes how something is produced – often with a safe-list of chemical treatments and approved practices.

    In chemistry, organic means the chemistry of compounds that contain carbon. Titanium dioxide and zinc oxide don’t contain carbon. They’re made up of metal and oxygen and classified as inorganic.

    Marking the categories as organic and inorganic makes more sense because all of the sunscreen chemicals used contain carbon, except for titanium dioxide and zinc oxide.

    It’s often said that inorganic sunscreens (titanium dioxide and zinc oxide) reflect UV off of the skin and organic sunscreens absorb UV and convert it into heat. In reality, for most of the UV spectrum they work very similarly.

    Organic sunscreens absorb UV because of the way the bonds between their carbon molecules are arranged… The energy from UV light promotes electrons in the conjugated carbon bonds of organic sunscreen molecules from a lower energy state to a higher energy excited state. The excited electrons in the bonds then relax or release the absorbed energy by stretching, vibrating, or bending – this turns that energy into heat.

    Inorganic sunscreens work very similarly – even though their structure is different from organic sunscreens… The principle behind the UV protection is exactly the same as organic sunscreens.

    There is a strong belief that these inorganic metal oxide sunscreens act by reflecting UV light instead of absorbing it, but this isn’t the complete story. UV light is divided into UVB and UVA. UVB is between 280 to 315 or 320 nm and UVA is between 315 or 320 to 400 nm. Inorganic sunscreens predominately absorb in the UVB spectrum and reflect in the long UVA (above 360 nm) and visible spectrum. Only about 5% of UVB light is reflected by inorganic sunscreens and the remainder gets absorbed and converted – just like organic sunscreens.

    Both organic and inorganic sunscreen particles can penetrate into the upper layers of the skin. If and how much they penetrate is dependent on properties like their particle or molecular size as well as the overall sunscreen formula. This isn’t a desired effect and formulators work to reduce the amount that penetrates. Modern organic sunscreens often have larger molecular sizes, chemical and physical properties, or even coatings which make it more difficult for them to penetrate past the surface of the skin.

    Keep in mind that skin penetration doesn’t mean that it’s causing harm to our bodies. There has to be a biological mechanism for it cause an effect. There is a lot current and ongoing research into this area, but we don’t have any strong answers yet.

    • makyo@lemmy.world
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      11 days ago

      As someone who gets to go to the skin doc every year for skin cancer checks - absolutely wear sunscreen.