The latest on sunscreens, sun blocks and sun burn

The link between sun exposure and skin cancer was made all the way back in 1918 by Dr. Norman Paul of Sydney, Australia.

There are components to solar radiation; long wavelength ultraviolet A (UVA) and short wavelength ultraviolet B (UVB). UVA is broken down into UVA and UVA2. For a long time it was thought only UVB caused sun damage to the skin, ie. sunburn.

Research over the past two decades has shown that UVA exposure is the key cause of skin wrinkling and solar damage. This also correlates with a higher incidence of skin cancer. In the early 80’s, it became obvious that sun screens needed to provide a greater degree of protection against UVA rays.

This is what is meant when we speak of “broad spectrum”. It means the sunscreen provides protection against both UVB and UVA.

Generally, I recommend a broad spectrum sunblock with a SPF of 30 or 35. 50 is okay too. Any SPF rating above 50 really doesn’t add much in extra protection but the ingredients are so concentrated they may be irritating to your skin.

What does SPF mean? The initials stand for Sun Protection Factor. If you use a sunscreen with an SPF of 20 it means it would take 20 times longer to get a sunburn than if you had NO sunscreen.

If you get a broad spectrum” sunblock with an SPF of 30-40 or 50, you should have excellent protection. I usually recommend patients liberally apply SPF20 in three coats to exposed areas prior to going out in the sun. You should reapply this every two hours or so.

Today, there are 17 chemical and physical (ie. zinc oxide) screens approved by the FDA.

There are NEW proposed ratings for UVB and UVA protection

Proposed UVB Labeling

• Low – SPF 2 – 14

• Medium – SPF 15 – 29

• High – SPF 30 – 50

• Highest – SPF 50+

Proposed UVA Labeling

Low - *

Medium - **

High - ***

Highest - ****

Some new changes to occur over the next one to two years:

- Sun protection factor would become sun burn protection factor.

- SPF numbers would be capped at 50 since higher numbers don’t provide any significant added protection.

- Terms such as “sunblock” and “waterproof” would no longer be allowed. “Sunscreen” would replace “sunblock”.

- Sunscreens that maintain their SPF numbers offer 40-80 minutes of total immersion would be labeled “water resistant” and not "waterproof".

- Also, sunscreens would contain a warning that sun exposure increases the risk of skin cancer and aging.

There you have it – just in time for your summer sojourn to the beach or Disney World. One other thing – "gooping" is not only allowed, but recommended

Sunscreens. What's new? What's best?

One of the most common questions I get asked is, “What is the best sunscreen?”

There is NO best but there are some basic principles to keep in mind when buying a sunscreen. To put it simply, buy one that is broad spectrum, has an SPF of 30-35 and is waterproof.

There is NO question that all types of skin cancer are related to the sun - the more sun, the greater risk. When we talk about the sun and its harmful rays, it is important to understand that the sun is composed of UVA, UVB and infrared rays. UVB is the one that causes the skin to get red and burn. When we talk about a sunscreen’s SPF factor we are talking about its protection provided to the skin for UVB rays.

These are the rays associated with sunburn. The SPF factor tells us nothing about UVA rays. UVA rays penetrate deeper into skin and can cause significant damage to the cells in the dermis. That is why it is important to get a broad spectrum sunscreen so you will get protection from the deeper penetrating sun rays.

Recent research seems to indicate that UVA can cause more damage to the cellular DNA which in turn can lead to more skin cancers. The problem right now is that there is no consensus on how rate sunscreens for UVA protection. UVA damage can result in the formation of free radicals and peroxides.

Solar rays are little bundles of energy called 'photons'. These photons are absorbed by the sunscreen. Once the photons are absorbed by the sunscreen, a reaction can take place where new secondary substances can be formed which themselves can cause redness, irritation and the like.

That is one of the reasons that many of the newer sunscreens on the market include anti-oxidants in their formulation. The jury is still out on their effectiveness.

Research is ongoing. I am going to throw some new names – medical terms for new chemicals or ingredients that can offer GREATER protection against damaging effects of UVA. Beware – some of these chemicals are a mouthful and you don’t have to learn how to spell them – just know they exist and the next time you but a sun block you may want to see if these new substances are in your sun block.

One of these new substances was helioplex. One of the new UVA absorbers approved by the FDA is Mexoryl. Neutragena did some studies on helioplex and found that it effectively absorbed sun rays between 290 nm – 400 nm, which are UVA. There are two new organic compounds that claim to be broad spectrum and photostable UV protection. Are you ready? Here we go – terephtralylidene dicomphor sulfonic acid and bis-ethyl hexyloxyphenol methoxyphenyl triazine. Wow! What a mouthful!

There are three trends in sunblock :

1. To promote physical blocks to the suns rays. There are inert substances such as zinc oxide and titanium oxide. I’m sure you all have been tot the beach and seen someone walking the beach with a ‘white’ nose. This is usually zinc oxide ointment. Looking great! Through new micro-technology, they can put it in sunscreens that are transparent.
2. Another new trend is to add antioxidants to sunscreen.
3. The other trend is to develop sunscreens that go on easier. These new products are dry feel, not sticky, oily-film like.

In short, select a sunscreen that is broad spectrum, has SPF of 30-35 and is waterproof. Go for it!