Summers are almost here !! It's time for Icecreams,mangoes , floral dresses and yeahSUNSCREENS ! Soon you will be flooded with various options to choose from. So, in today's "DOC Talk with Miss Derma"here's a brief account of what you need to look for while purchasing a good sunscreen !
It would be boring and monotonous if I try to cover everything about Sunscreens in one article. Hence, I have decided to make a series on this.
So, here's PART- I
*geez, I already feel teacher-y* : D
I had already done a similar post earlier here , but let's recaptulate.. because using proper sun protection method is more effective than any other cosmetic product and procedures !
*adjust specs, goes to the blackboard, starts scribbling in capitals*
What is a Sunscreen ? Sunscreen ‘screens’ the sun rays which are falling on your skin and thereby lets some of the ultraviolet rays to get through.
What is a Sunblock ? Sunblock ‘blocks’ all the sun rays falling on you and thereby deflects all the ultraviolet rays. But no sunscreen can effectively block all parts of the UV spectrum. Hence, FDA no longer allows the term "Sunblock" to be used on product labeling
Some points on UVA and UVB rays ~
- Ultraviolet radiation is the primary cause of skin cancer, exogenous skin aging, wrinkles and blotchy pigmentation.
- UVA - comprises over 90% of UV rays reaching earth.It penetrates deeper into skin and is the main cause of skin wrinkling and aging. It is also related to skin thickening. And is even thought to be a cause of Melanoma.UVA radiation can pass through glass and the amount reaching the surface of earth remains constant throughout the day
- UVB- comprises the rest of UV rays reaching earth.It is the primary causative agent for Skin cancer.It is blocked by glass and the amount reaching the earth's surface varies by time of day! (max between 10am and 4pm)
SPF/ Sun Protection Factor
It refers to the ability of a sunscreen to block UVB rays, which cause sunburns, but not UVA rays. It is an index of protection against sunburn. Theoriticaly , if you are using a sunscreen with SPF 15, means, you can stay in the sun 15 times longer (without visible redness)
So, does that mean using SPF 100, you can stay in the sun..like forever?? NO !
Why ? Because we never apply sunscreen in proper way. And by "proper way " I mean a proper "dosage". Yes, a sunscreen is essentially a drug and not a cosmetic.
The international standard quantity of sunscreen per unit of skin surface is 2mg/cm2. If this is to be strictly followed, we would require approximately 30ml of sunscreen for the entire body ( to achieve that thickness) !
Studies have shown , the ultimate protection we get from our sunscreens is one-third of the spf we use!
Lets make it clear with an example here ~
A sunscreen with spf 15 should gives us 15times protection from the sun( than bare skin). But Because of the faulty application , we achieve only a third . That is , only a 5fold protection.
Just because of the above reason , it is advisable to use a sunscreen with a high SPF . Otherwise, basically an SPF 15 sunscreen blocks 93 % of UVB rays, SPF 30 blocks 97 %, SPF 50 blocks 98 %, and SPF 100 blocks 99 %.... Ultimately the thing is Spf 15/30 if applied/used in the correct way and dosage would give you optimum protection against sunburn. As,you increase the SPF number (after 50), the percentage of protection actually varies little about 0.05-1 % !
*So, class..any doubts?? Feel free to ask at the end of the class in the comments below *
Protection factor UVA / PFA
Goal of UVA protection factor is to protect skin from persistent pigment darkening induced by UVA exposure
A much complex equation goes into this calculation , but may be this will help you get the picture...
- PA + = PFA value of 2 or more but less than 4
- PA++ = PFA value of 4 or more but less than 8
- PA +++ = PFA value of 8 or more
**How to Use Sunscreen**
As mentioned previously, we need to use approximately 30ml of the product in our body to achieve the SPF and PFA mentioned in the label .
- Use sunscreen even when you are indoors, even when its cloudy outside, even if it is not "summer"
- Use a thick layer of the product on all exposed areas of your body. Be generous !
- If you plan to go out in sun , apply sunscreen 30mins prior
- Repeat application every 2 hours
- Use other methods of sun protection like umbrella, full sleeved clothes , hats etc .
You can go through all my sunscreen reviews HERE
My Next class, post will be on "Ingredients to look for in sunscreens ".
Please let me know if you want a post on " Sunscreen for kids" and " Sunscreen and Swimming " in the comments below
Images source : Google images
