Like almost any topic in the field of health and wellness, it seems there is a tangled web of research and opinions when it comes to sun exposure and sunscreens. Should we wear SPF 50 sunscreen for our walk from the house to the mailbox, or should we shun all sunscreens in our quest to increase ourlevels as much as possible? Do we buy sun protective clothing to safeguard every inch of our skin from the damaging UV rays, or should the real cause of our cancer fears be the sunscreen ingredients themselves?
As usual, I’m going to seek the balance on this controversial topic and try to share with you some brief synopses of the current research on the issue. I lean heavily on the EWG 2010 Sunscreen Guide but realize that multiple sources are necessary.
What is the Difference Between Sunscreen and Sunblock?
Before we get into the topic too deeply, let’s start with terminology. In general, tubes of sun protection use both terms fairly interchangeably, but officially sunscreens use chemical “absorbers” and sunblocks use physical blockers to protect the skin from UV radiation and sunburns.
The ultimate questions for any suncream is: Does it protect from both UVA (cancer causing) and UVB (skin damaging/burning) rays?
Look for terms like “broad spectrum” coverage or ingredients like avobenzone, zinc oxide and titanium dioxide, all of which protect from UVA rays. All sunscreens will protect from UVB rays because you’d notice if it wasn’t working!
How Sunscreen Works
“Sunscreens absorb UV energy and have to be absorbed into the upper layer of skin to really get up to full speed,” says Darrell Rigel, clinical professor of dermatology at New York University Langone Medical Center. (source) A chemical reaction takes place between the sunscreen ingredients and the UV rays to “screen” your body from most of the effects of the sun. That’s why the instructions on the sunscreen bottles say to put it on 20 minutes before being exposed to the sun. It needs that time to sink in to your skin before its full SPF is realized. (Sources: 1, 2, 3)
How Sunblock Works
Sunblock, on the other hand, is called a “physical” block rather than chemical. It sits on the surface of your skin rather than being absorbed into it. Most sources say that sunblocks “reflect and scatter UV light.” (1, 2, 3, 4 and many more)
Contrary to popular definition, the founder of Kabana, one of the products I’m testing for next week’s review, disagrees with that explanation and claims instead:
“Zinc oxide has a broader UV absorption profile than titanium dioxide, which is noteworthy, because much misinformation populates the media about how these chemicals protect us – they do NOT reflect and scatter in the UV spectrum – rather zinc oxide absorbs UV and does so very effectively. The media (and ‘experts’ alike) need to investigate the physical chemistry of these compounds, rather than assume they reflect UV light because they look white in the visible spectrum. They do reflect in the visible, but would look black in the UV.” (source)
Either way, sunblocks use minerals that sit on the surface of the skin (usually zinc oxide and titanium dioxide) rather than chemicals that sink into the skin to protect one from the sun. Mineral sunblocks begin working right away, so there’s no need to apply 20 minutes before sun exposure.
What is a Sunburn?
What exactly are we trying to protect ourselves from when we use sunscreen, anyway? (Note: I will use the term “sunscreen” alone to refer to both sunscreen and sunblock when both apply simply to avoid having to write sunscreen/sunblock constantly.)
According to this video from a dermatologist: Ultraviolet rays of sun penetrate the skin and cause damage to the skin. Inflammation and redness is a first level sunburn. Blistering means deeper damage to the skin. Tanned skin is superficially damaged skin. Tanning is the skin’s way of trying to protect the skin from damage. UV rays are radiation, so a sunburn is radiation damage.
To be Continued…
When you’re your own boss, you get to change the schedule around sometimes. My best laid plans were foiled by lack of time and discipline, and I’m not willing to write a subpar post without all the information. This research post will be continued Tuesday after my family returns from camping:
Forecast is 85F high, 65F low, lots of sun. I’m taking 25 sunscreens (sunblocks!) with us and subjecting them to one last test on this gorgeous beach at Lake Michigan. (Are you jealous?) I’ll return armed with data and anecdotes and review them all for you Tuesday or Wednesday. The following day I’ve got five sun protective clothing companies to run through the wringer and over $400 in giveaways total!
We’re using the sample 2-night meal plan from Kitchen Stewardship in the Big Woods: A Family Camping Handbook with Real Food Options (buy it here), along with a few of the extensions to last another day. We’re dragging my sister-in-law and her husband along – to the deep woods with no toilet – and we’re going to make nature appreciators out of them if it kills us! 😉
I’ve been working hard all week preparing food for six people for four days, so I guess that’s my excuse for leaving you hanging on the sunblock research. Here’s what you can look forward to in Part Two RIGHT HERE:
- The Risks of Chemical Sunscreens
- Memory Helps to Find the Safer Options
- Sunscreens and Sunblocks Release Free Radicals
- Mineral Sunblocks: Nano vs. Micronized Particles
- Why Zinc Oxide Better Than Titanium Dioxide?
- The dangers of sunshine?
- Skin Cancer: a Sun Issue?
- Vitamin D: The benefits of sunshine
See you Tuesday!
There are affiliate links in this post from which I will earn a small commission.