Here are some thoughts from medicine web about SPF Medicine Web

The latest sun screens have been offering SPF that is way higher than what we have been used to. Coppertone, for instance, rolled out its easy-to-use sprays with SPF 70+, while Neutrogena offered an Ultra Sheer Dry Touch lotion in SPF 85, while another Neutrogena sunblock has a high sun protection factor of 100. This has caused a number of dermatologists to cry foul, complaining that SPF has turned into a numbers game.

But what really is the difference that a SPF 100 sunblock can bring compared to the usual products with SPF 30? Here are what the experts say.

You can never be fully protected against the sun's rays

SPF measures how much a product shields you against the sun's ultraviolet B rays, or UVB radiation, which can cause sunburn. However, even the highest of SPF's cannot protect you fully against the more penetrating ultraviolet A radiation, which can cause skin aging and even skin cancer.

The difference is just minimal

A sunblock with SPF 100 blocks 99 percent of UVB rays, while SPF 50 could protect you for up to 98 percent. Meanwhile, products with SPF 30 can deflect 96.7 percent of the sun's rays. Such miniscule difference does not matter, really, but buying a sunblock with a higher SPF could only end you paying more for just a little more protection.

You need a lot of sunblock to protect yourself

In order to get the SPF amount as advertised, you must apply an ounce or a full shot glass of sunblock on your body. This is a huge difference compared to those who only apply about half the recommended amount, especially those who buy a three-ounce tube then make it last for up to a whole month of outings. Remember that putting not enough sunblock could only yield half the protection on your skin.

Dermatologists actually recommend using sunscreens with at least SPF 15, as well as UVA-fighting ingredients like avobenzone or Mexoryl SX. They also advise wearing a wide-brimmed hat to protect yourself against the harsh sun's rays.

Last edited by CaliHawk; 05/03/11 02:22 PM.