Sunscreens Demystified

Posted by Fernanda da Silva Tatley on

Are sunscreens with a high SPF better sun protectors?


SPF is the abbreviation for” sun protection factor”.

 

SPF is a indicator of the ability of the sunscreen to “redirect” UVB rays away from your skin, as if you had your skin coated with a mirror.

 

The SPF level reflects the degree of protection against skin sunburn in comparison to skin that has been exposed to the sun without sunscreen.

 

In principle the best sunscreen is that with the highest SPF level, however SPF 30 is only marginally more protective from UVB rays than SPF 15! This means that SPS 30 is NOT twice as protective as SPF 15.

 

And so, the protection of SPF 60 against UVB is hardly more noticeable that that of SPF 30… and so on! 

 

Then, don’t forget that these levels of protection assume that the sunscreen has been applied correctly, thickly enough, and that it is being reapplied after swimming or excessive sweating.

But, protecting against UVB is NOT enough, because there are 2 harmful types of UV rays – UVA and UVB.

  • UVA accelerates premature skin ageing, causing wrinkles and liver/dark spots. 
  • UVB burns the skin. 

Excessive exposure to UVA and UVB can lead to skin cancer. 

Thus, you need a broad-spectrum sunscreen that protects against both types of radiation. This is what you should be looking for, NOT just the SPF level. 

Besides regardless of SPF level sunscreens should be re-applied every 2 – 3 hours.

 

What are the best sunscreen agents?

Zinc oxide is the best UVA and UVB protector, but it tends to make the sunscreens more difficult to spread and whiter on the skin. To overcome this issue “invisible zinc” was developed.

“Invisible” zinc is a very small size particle of zinc – “nano zinc”. However, many studies have shown that because the nano zinc is much smaller than our skin pore size, it gets taken up very easily.

So, the very particle that you want as a shield disappears into the skin, and many study have show zinc accumulation in our organs. Fortunately, as zinc is an essential metal for our physiology, this may not be a problem. But, why use a sunscreen that does not stay on the skin surface?

Titanium dioxide offers only protection against UVB, but it has more slip.

Chemical sunscreens also called “organic sunscreens” transform UV radiation to heat. BUT, the designation “organic” is purely a chemical tern that has nothing to do with “organic certification”.

Many studies have shown that these chemical sunscreens accumulate in our body, and as they are active ingredients some of them have been demonstrated to be carcinogenic, i.e. cancer forming.

Examples of these sunscreens: avobenzone, cinoxate, ecamsule, menthyl anthranilate, octyl methoxycinnamate, octyl salicylate, oxybenzone or sulisobenzone.

In summary, get to know sunscreens, use them all year around, use protective clothing, stay in the shade in the peak hours (10.00 am – 4.00 pm), and don’t get a false sense of security by using a high SPF level!

 

Manufacturers calculate SPF based on how long it takes to sunburn skin that's been treated with the sunscreen as compared with skin that hasn't been treated with sunscreen.

Theoretically, the best sunscreen has the highest SPF number. It's not that simple, however. When applied correctly, a sunscreen with an SPF of 30 will provide slightly more protection from UVB rays than does a sunscreen with an SPF of 15. But the SPF 30 product isn't twice as protective as the SPF 15 product. Sunscreens with SPFs greater than 50 provide only a small increase in UVB protection.

Also, keep in mind that sunscreen is often not applied thoroughly or thickly enough, and it might be washed off during swimming or sweating. As a result, even the best sunscreen might be less effective than the SPF number on the bottle would lead you to believe.

 

Rather than looking at a sunscreen's SPF, choose a broad-spectrum sunscreen that will protect you from UVA and UVB rays.



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