Anti-Aging 101: Photoaging, AKA: Why You Shouldn't Tan!

Remember this exciting picture from last week, where I showed you what ages us? Yes, I know, you were impressed with my mad Photoshop skills. Well, this week we'll discuss one of these items: The sun. (For those of you wondering about the DNA Helix, just go look at your mom and grandma to get an idea of how you'll age. If you have a strong jaw and prominent cheekbones then you'll age even better.)

I think it should be obvious that smoking ages you. I might post about this at some point, but for now we're going to concentrate on one of my favorite topics.

Anyways... Read on to know why you shouldn't forget your sunscreen. As if avoiding things like Cancer aren't enough and you need a reason related to vanity.

If you aren't familiar with them, you might want to glance at my posts on the dermis and epidermis

So, it actually took me quite a bit of reading to figure out what the sun does to your skin. Strangely enough, it wasn't really well delineated in any of my derm textbooks. I'm pretty sure that's just because it's pretty basic for someone who is actually a dermatologist. (I'm not, I'm an intensivist. I wanted pretty diagrams and lots of skin histology pictures.)

So, what does the sun do to your skin? A bunch of things. And, note that while many of the effects are initially temporary, some of these things will be "turned on" longer and longer with more UV exposure. I'm talking about UV exposure that doesn't even result in a sunburn or tan. So, short amounts of repeated sun exposure... still creates changes in the skin and can result in aging. So, wear your sunscreen every day!

• UV exposure induces pro-inflammatory chemicals known as cytokines (in particular TNF-alpha, IL-1, IL-6 and IL-8 if you are interested). These pro-inflammatory chemicals in turn not only cause local inflammation (and tissue damage), but will also activate some of these cells to create reactive oxygen species and MMPs.

• Localized melanocyte proliferation is seen, you'll see this as hyperpigmentation or freckling in the skin.

• Increased reactive oxygen species (ROS) are seen with UV exposure, damaging pretty much everything in site. UV exposure can increase the skin's own anti-oxidant production for a day or two, but over time the skin is no longer able to do this to the same extent and sun will increase the ROS. ROS are linked to photoaging, cancer and inflammation of the skin.

• UV exposure will increase production of matrix metalloproteinases (MMPs). Basically this is a class of enzymes in the dermis that can go around and cut up/degrade collagen and elastin. You'll see clumping and decreased levels in the remaining collagen and elastin, both of which will cause sagging and loss of elasticity of the skin. This increase in MMP levels starts within hours of sun exposure and can be sustained with repeated UV exposure.

What does it look like?
While the results of photoaging such as wrinkles and loss of elasticity are pretty much the same as regular aging, they'll be accelerated. You'll see both fine and coarse wrinkling, hyperpigmentation, texture changes and loss of pigmentation. I'm not even mentioning the DNA changes that occur with UV exposure, causing both pre-cancerous and cancerous areas.

How can it be treated?
Mostly, it shouldn't be treated, it should be prevented! So, start wearing your sunscreen. Tomorrow is the first day of my new Sunscreen 101 series (obviously, a companion to the anti-aging 101 series), and I'll be reviewing a TON of sunscreens after a few weeks of sunscreen basics each Tuesday. For treatments, you'll really need to see a dermatologist. They can laser and peel your skin to help treat the skin, but it is much better to not have the damage in the first place since the treatment can't fix all of the damage.

Knowing a little bit more about photo-aging, and aging itself does give us a few targets. You can target the ROS by using anti-oxidants. Increase cell turnover with products like peptides and retinoids. You can even target those MMPs with a MMP-inhibitor (Only Dr. Wexler makes those products). Stay tuned for more posts on different ingredient classes and how to get them to work for you!