First things first, what is the difference between UVA and UVB rays?
Both UVA and UVB rays are forms of ionizing radiation from the sun. Both types of rays cause damage at the cellular level.
Kevin Maguire, M.D., University of Vermont Associate Professor of Surgery and Chief, Division of Plastic, Reconstructive and Cosmetic Surgery (Photo: UVM Medical Center)
The information, below, was originally published on the University of Vermont Medical Center’s blog in a post, titled “Fun in the Sun? How to Protect Your Skin This Summer . . . & Beyond.”
Below, Kevin Maguire, M.D., F.A.C.S., University of Vermont associate professor of surgery and chief, Division of Plastic, Reconstructive and Cosmetic Surgery, answers questions on how to protect your skin from damage and skin cancer. For Maguire, and many of his plastic surgery colleagues, skin cancer management is the number-one reconstructive case nationwide. Fortunately, most skin cancers are curable depending on type and how quickly they are diagnosed. Learn how to help prevent skin cancer before it even gets started, below.
First things first, what is the difference between UVA and UVB rays?
Both UVA and UVB rays are forms of ionizing radiation from the sun. Both types of rays cause damage at the cellular level. This sun-related damage can be seen beginning at the age of thirty, and even younger. Both UVA and UVB rays do so by creating mutations in your DNA. When this cellular DNA damage is not corrected, it can result in skin cancer and premature aging of the skin.
You may have heard that UVA rays are not damaging, and that UVB rays are the culprit. That’s false. Both A and B can cause skin damage or skin cancer if left unchecked or uncorrected. So, look for broad spectrum skin care products that block both types of rays.
Is wearing a cosmetics skin product with SPF, such as moisturizer or foundation, enough to protect my skin?
It’s a reasonable start. Many daily cosmetics may have some form of protection, which is perfectly fine for everyday activities, such as getting out of your car to go to work or shopping – activities where you are primarily indoors. If you are looking to go out on a hike, head to the beach, play an outdoor sport or work outdoors – any situation where you will be outside for an extended amount of time – you will need to use a true skin protection product, like sunscreen or sun block to help effectively prevent the sun damage.
I’ve looked at sunscreens, but I don’t know what SPF means. What is it?
SPF stands for Sun Protection Factor and measures the relative level of protection from the damaging UVB sun rays. It’s a ratio of how long you can stay in the sun using that product as opposed to using nothing. But it’s important to realize the SPF rating applies only to UVB protection, not UVA. For example, if a pale Caucasian male (an Irishman like me) goes out into the sun without any protection, he will probably develop sunburn within 20-30 minutes. That’s considered Fitzpatrick Type 1 skin. The Fitzpatrick scale is a numerical classification for human skin color. A darker African-American is considered a Fitzpatrick Type 6. You can take a quiz to find out your skin type.
A person may use their skin type to determine what type of SPF they need. You will want to multiply the number of minutes it takes you to develop a sunburn by the SPF to find out how long the sunscreen will protect you. For example, if my skin normally burns after 10 minutes and I apply an SPF 15 sunscreen, it will allow me to stay in the sun without burning for 150 minutes. Generally, going up to SPF 50 is advisable – anything above that offers no significant additional protection. For example, an SPF 15 blocks 93% of UVB and SPF 30 blocks 97%.
It’s important to note that children are an exception – all children and infants must use the same level of skin protection, regardless of skin type.
Remember to re-apply your sunscreen every two hours. Also, sunscreens should be only one of the strategies in your skin health program. You should also consider covering up with clothing that filters out sun (not all garments do – you can still get sunburned through a mesh fabric) and floppy hats. Seek the shade and avoid direct sun exposure during the interval of 10 AM to 4 PM when the sun’s rays are most potent.
Can you combine SPFs?
No. SPFs are not cumulative.
Why do some people tan and why do others burn?
It has to do with your body’s PROTECTIVE response. Tanning is your body’s response to the insult of ionizing radiation. As the sun penetrates your skin, it turns on a protective mechanism. A cell named the melanocyte becomes turbo charged and increases the amount of pigment in your skin. This increase in the amount and density of pigment causes the skin to turn brown, or tanned. This tanned or darker color is an attempt to decreasing the ability of the ionizing radiation to penetrate into your skin and cause cellular damage.
So, tanning is a protective response. The reason why some people tan relates back to skin type. It depends on the density of the cells responsible for making melanin, the melanocyte, and the amount of pigment produced. In a Caucasian this density is lower than in African-Americans. A Caucasian’s ability to produce this pigment is much lower – and that’s why some people burn.
I do not recommend tanning, outdoors or indoors. Tanning beds should be avoided at all costs. Studies show a steady increase in the diagnosis of basal cells, squamous cells, and melanomas in people in their twenties and thirties. Additionally, these skin cancers tend to be very aggressive. If you must have a tan, please consider artificial tanners or a professionally applied spray tan. Although this approach is temporary and short lived, it is much more healthful.
Do medications have any effect on sun/skin protection?
It depends on the type of medicine that you are taking. For instance, some antibiotics make you sun sick and some skin products may make you sensitive to the sun. Many patients use Retin-A for the treatment of acne and certain aging processes. It can make you sun sensitive and susceptible to sunburn. Talk to your doctor about your specific medications and how they interact with the sun.
How often should people check their skin for abnormalities?
Get into the habit of checking your skin monthly, same as you would your self-breast or self-testes exam. Use a mirror to review your skin from head-to-toe (including your back and the bottoms of your feet).
Reach out to your primary care doctor, dermatologist, or plastic surgeon if you find anything peculiar as soon as possible (within 90 days). Peculiar means skin growths that are:
- Red and stay red
- Pearly white and raised
- Ulcerated
- A pigmented freckle that is oozing, itching, bleeding, has more than one color to it (brown, blue, black), or has irregular edges.
- Persists or recurs.
The old adage that an ounce of prevention is worth a pound of cure accurately explains your skin health and sun exposure. The amount of sun damage is cumulative through the years. So, it’s never too late to start but the earlier you start a solid sun protection plan the better off you will be. Solid common sense and diligence will assure that you will enjoy good skin health for many years to come.