Approximately 20% of Americans will develop skin cancer at some point in their life, making skin cancer the most common cancer in the United States. July is UV Awareness Month, making it the perfect opportunity to educate yourself about the dangers of ultraviolet (UV) radiation, the differences between UVA and UVB rays and how to protect your skin.
Dr. Joel Schlessinger, board-certified dermatologist, Mohs surgeon and cosmetic surgeon, explains, “UV radiation from the sun is a major cause of skin damage, leading to premature aging, sunburns and skin cancer. It’s essential to protect your skin from UV radiation every day by wearing a broad-spectrum sunscreen with at least SPF 30 or more.”
He adds, “There are two primary types of UV rays, UVA and UVB. Knowing the differences between these rays and how to protect yourself is crucial for maintaining healthy skin.”
What’s the difference between UVA and UVB radiation?
Dr. Daniel Schlessinger explains, “A helpful mnemonic for explaining the differences between UV rays is: UV-Aging versus UV-Burning.
UVA (“UV-Aging”) rays account for about 95% of the UV radiation that reaches the Earth’s surface. These rays have a longer wavelength and can penetrate deeper into the skin, affecting the dermis, the skin’s thickest layer. UVA rays are primarily responsible for causing skin aging, long-term skin damage and may contribute to some skin cancers. This can lead to wrinkles, age spots and loss of skin elasticity. Unlike UVB rays, UVA rays are present with relatively equal intensity during all daylight hours throughout the year and can penetrate clouds and glass. It’s essential to protect your skin from UVA rays every day by wearing a physical or chemical sunscreen, even on cloudy days.
UVB rays (“UV-Burning”) rays are only responsible for about 5% of the UV radiation reaching Earth but are more intense and cause more immediate damage than UVA rays. These rays primarily affect the outer layer of the skin, the epidermis, and are the main cause of sunburns. UVB rays also play a significant role in the development of skin cancer. Unlike UVA rays, UVB rays vary in intensity depending on the time of day, season and altitude. They’re strongest between 10 a.m. and 4 p.m. during the summer months and can cause damage and sunburn in a short amount of time.
What is SPF anyway?
Sun Protection Factor (SPF) measures a sunscreen’s ability to protect the skin from UVB rays, which cause sunburn and contribute to skin cancer. The SPF number indicates how long it would take for UVB rays to redden the skin. For example, if a sunscreen has an SPF of 30, it would take thirty times longer for your skin to burn than if you were wearing no sunscreen. SPF works by absorbing, reflecting or scattering sunlight through active ingredients. It’s important to apply sunscreen liberally and reapply every two hours, or more frequently if swimming or sweating, to ensure adequate protection.
How do I choose between chemical and physical sunscreen?
When it comes to protecting your skin from UV radiation, sunscreen is your first line of defense. There are two main types of sunscreen: chemical and physical. Understanding the differences between them can help you choose the best product for your skin type and lifestyle.
Dr. Joel Schlessinger explains, “Physical sunscreens shield skin by deflecting the sun’s rays, while a chemical sunscreen absorbs them. Essentially, chemical sunscreens contain chemical ingredients that offer a different form of protection. Chemical sunscreens work better and longer while also going on a bit more sheer in appearance, but they also have some allergic issues and the concerns of usage in pregnant women and children. Personally, I prefer physical sunscreens when and if possible, but if I am going out for a long time or in intense sun I will layer with chemical sunscreens..”
Dr. Daniel Schlessinger, board-certified dermatologist as well as Mohs surgeon and cosmetic surgeon, adds, “Your choice of sunscreen typically depends on personal preferences, but a few considerations can help you decide which is best. I, too, suggest physical sunscreens for pregnant women, children and infants. Physical sunscreens are generally less likely to cause allergic reactions or skin irritation but need to be reapplied frequently. The ingredients that make up chemical sunscreens have been available for more than 20 years in the United States and there has been an ongoing need for better and more chemical sunscreen options, but for now we have limited options. Fortunately, many sunscreen manufacturers have worked very hard to get the most out of what we have.”
Chemical sunscreen
Chemical sunscreens contain organic carbon-based compounds that absorb UV radiation and convert it into heat, which is then released from the skin. Ingredients such as avobenzone, octinoxate and oxybenzone are commonly found in chemical sunscreens. These formulations tend to be more lightweight and can be easier to apply without leaving a white residue. However, some people with sensitive skin may experience irritation or allergic reactions to certain chemical ingredients.
Physical sunscreen
Also known as mineral sunscreen, physical sunscreen contains active mineral ingredients like zinc oxide and titanium dioxide. These minerals sit on top of the skin and physically block and reflect UV rays. Physical sunscreens provide broad-spectrum protection against both UVA and UVB rays and are generally less likely to cause skin irritation. They are often recommended for sensitive skin and for use on infants and children. One drawback is that physical sunscreens can sometimes leave a white cast on the skin, although many modern formulations have addressed this issue with tinted or micronized options.
Choosing the right sunscreen for your skin
Understanding the differences between UVA and UVB rays is essential for protecting your skin from sun damage and maintaining a healthy complexion. Both types of rays pose significant risks, making it crucial to use a broad-spectrum sunscreen that provides protection against both.
Dr. Joel Schlessinger recommends EltaMD UV Clear Broad Spectrum SPF 46 Facial Sunscreen. He explains, “This is the best sunscreen for people on-the-go and works as a great base layer. In addition to providing excellent sun protection, it also calms and treats blemishes with 5% high-purity niacinamide and lactic acid.”
Colorescience Total Protection No Show Mineral Sunscreen SPF 50 is a favorite of Dr. Daniel Schlessinger. He adds, “This 10% zinc-oxide sunscreen is an all-mineral formula, yet it provides a sheer finish without any white cast. It includes Colorescience’s proprietary EnviroScreen Technology, which further protects skin against damaging environmental factors like pollution.”
Whether you choose a chemical or physical sunscreen, the most important thing is to apply it regularly and liberally, especially during peak sun hours. Dr. Joel Schlessinger recommends using a half-dollar-sized amount for the face and neck, and enough to fill a shot glass for the rest of the body. By staying informed and taking proactive steps, you can enjoy the sun safely and keep your skin looking its best.
Maintaining healthy skin
At Schlessinger MD and LovelySkin Spa, our team is dedicated to helping you achieve your very best skin. If you’re interested in addressing specific skin concerns you can book a consultation with a member of our team to discuss your goals. If you’d like to speak to us directly, you can call or text us at (402) 334-1226.