Here’s some link love for MssJackson …
Mssjackson asks…Does zinc oxide and titanium dioxide in products give sunprotection the same way?
The Right Brain responds:
Yes, MJ, zinc oxide and titanium dioxide have the same mode of action: They are both minerals and they both physically scatter the rays of the sun to prevent sunburn.
How is sunblock different than sunscreen?
These minerals are generally referred to as sunblocks which describes the mode of action of blocking the sun’s rays. Compare that with the alternative which are typically referred to as “chemical sunscreens.” (Note: To be accurate, ALL these ingredients are chemicals. And sun “block” versus sun “screen” is not strictly a technical term either. But this is how the market refers to these ingredients so we’ll follow that convention for today’s post.)
Sunscreens work by absorbing UV rays and changing them into a different wavelength of light that is not harmful to skin. Because sunscreens are chemically reactive, they can cause skin irritation especially at higher concentrations. This is why you see so many concerns raised about chemical sunscreens and photosensitivity. Oxybenzone, octyl salicylate, and octyl methoxycinnamate are examples of UV absorbers.
Pro and con
If both types of ingredients provide the same benefit yet chemical sunscreens have potential irritation concerns, why doesn’t eveeryone just use mineral sunblock? Until fairly recently the reason was that sunblocks were not very aesthetically pleasing to use. Because of their large particle size, these ingredients always left a white film on the skin. (Think of the noses of the life guards at your local pool.) In the last several years, mineral sunblocks with smaller particle sizes have been developed to reduce this whitening effect. However, concerns have also been raised that micronized titanium oxide can penetrate the skin and cause other health issues. The products that we have right now are not perfect, but they’re better than risking skin cancer by wearing nothing.
Image credit: Flikr
{ 11 comments… read them below or add one }
Chemical sunscreen irritates my face a little bit. That’s why I choose not to wear it on the face. Instead I use “physical” sunblock, even though it’s a bit more difficult to wear. It is definitely sticky and not easy to apply, but it makes a good primer too!
I guess for me personally, it’s physical sunblock for the face as it’s very sensitive and chemical sunscreen on the body.
Thank you so much for answering my question!
Is “Photodynamic Therapy” by DERMAdoctor just a sunscreen then? It supposedly has the power to turn harmful uv rays into red light therapy. Does regular sunscreen do the same?
“micronized” is already old hat – we already have nanoparticles available of TiO2, early reports indicate that it is not a problem, doesn’t get absorbed by the body, but still need more info.
@WestHillsManor: I don’t know if the chemistry is exactly the same but it’s certainly the same principle.
Clive: thanks for the clarification. I actually meant to refer to the nano particle issue.
I always thought that sunscreen and sunblock are the same thing because the purpose of both is to protect from harmful rays of the sun.
There’s always the solution of using products containing both chemical and natural filters..
Update: according to new US regulations that take effect this year, the term “sunblock” will no longer be allowed.
I still can’t use either right now on my face. I wonder if there way convince my dermatologist to do patch allergy test, right now my dermatologist says there are way to many chemicals in sunscreen and sunblocks to determine which ones are causing me contact dermatitis. So I living without either.
Since I don’t burn and its unheard of for people from sunny island where I am from to get it skin cancer combined with the fact I am now living in a country which most of the people will not get enough sunlight to even get the right amount of Vitamin D per day I think I have a very low chance of getting skin cancer in my life time without sunscreen.
Hyspin, I still think you should ask your derm if maybe you have periorificial dermatitis, which there are treatments for. I’m not a doctor, but I guess I kind of hope that’s what it is because you could get treated if so. In the meantime, you could try a powder sunscreen (like colorescience).
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