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Friday, September 14, 2007

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!

1 comment:

  1. I live in Sun Valley where the climate is so harsh on my face... I really need help. I look a lot older than I really am. I am planning on coming to Florida for a vacation and need to make an appointment with you. You look like Paul Newman... have you heard that before? Do you do the new Artefill?? I hear it works a lot longer than the rest of the fillers... can we meet for drinks and you can tell me what I need? Also do you accept Care Credit so that I can charge this procedure?? Your friend, Diane

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