From UVA to SPF: Understanding Sunscreen

With summer so close we can almost taste it, there’s one thing that’s top of mind for the Standard Dose team: sun protection. While wearing sunscreen is a 365-day deal (more on that later), finding the perfect stick or lotion has likely crossed your mind more frequently as temperatures start to rise. But if just the thought of deciphering jargon or scanning ingredient lists has you breaking out in a pre-season sweat, you’re not alone. Lucky for you, we’re passionate about protecting our skin as well as helping you to do the same. 

Let’s start by recapping why sun protection is so important. While the sun is often our friend (it’s the best source of vitamin D and triggers the release of mood-boosting serotonin in the brain), it also emits ultraviolet (UV) radiation that can damage our skin cells’ DNA and cause serious health problems. There are two types of rays within the UV spectrum that are harmful to our skin: UVA rays and UVB rays. UVA rays have a shorter wavelength and are responsible for damage like skin aging, wrinkles, and tanning. That’s right—tanning isn’t a perk of time spent outdoors and is actually a sign of skin cells in trauma. UVB rays, on the other hand, have a longer wavelength and prompt sunburn. Both rays contribute to skin cancer, a disease that claims the lives of more than two people in the United States every hour. That’s why choosing a sunscreen labeled “broad spectrum” is important: they contain ingredients that protect your skin from both types of UV rays, not just one, and are the only kind we stock at Standard Dose. 

Another acronym that’s vital in understanding sun protection is SPF. It stands for “sun protection factor” and tells you how long it would take for UV rays to burn your skin while wearing that sunscreen as directed versus how long it would take had you not applied. For example, wearing an SPF 30 sunscreen means it would take about 30 times longer for your skin to redden than had you not been using it. The SPF number also reflects the number of rays the formula allows to reach your skin, with SPF 30 allowing about 3% to penetrate and SPF 50 permitting closer to 2%.

While your next question is likely “What level of SPF is right for me?” there, unfortunately, isn’t a one-size-fits-all answer here. Many different factors will determine your SPF needs such as a personal or family history of skin cancer, certain genetic conditions, and even the activities you’ll be enjoying. However, the American Academy of Dermatology recommends using at least SPF 30, which means you should view any products you use that have a lower SPF value (such as a moisturizer with SPF) as an added bonus rather than a replacement for a dedicated, broad-spectrum sunscreen of this strength. 

Another area that’s often confusing about sun protection is the difference between chemical and minerals sunscreens. To understand this, it’s helpful to first think of chemical sunscreens like a sponge: they contain ingredients that absorb the sun’s rays, create a chemical reaction, and turn the rays into heat that’s then released from your skin. Conversely, mineral sunscreens (which are sometimes called physical sunscreens) are like a shield, they sit on top of your skin and reflect the sun’s rays before they make contact. You can tell whether a sunscreen is mineral or physical by looking at the ingredients. Mineral sunscreens will list zinc oxide or titanium dioxide, while chemical sunscreens will note other active ingredients such as oxybenzone and avobenzone. 

In 2019, the FDA issued a proposed rule which asked manufacturers to provide more information about the safety of many active ingredients found in sunscreen. However, it proposed that two ingredients were already “generally recognized as safe and effective” (GRASE): zinc oxide and titanium dioxide. These are the ingredients associated with mineral sunscreens, which are the only kind of sunscreen we currently carry. As well as being safe, these ingredients can also benefit the skin. For example, zinc oxide has anti-inflammatory properties and is more suitable for sensitive skin. When selecting our curation of sunscreens under the mineral umbrella, we also make sure to avoid any that contain cyclic silicones as they pose an environmental risk. 

How ingredients appear in mineral sunscreen formulas is also important to consider. Many sunscreens contain zinc oxide or titanium dioxide nanoparticles (tiny particles of a substance) so the formula doesn’t leave a white film. However, right now there isn’t enough information to totally confirm how nanoparticles are absorbed in the body and what effects they might have. That’s why we’ve chosen to offer non-nano mineral sunscreens and have taken extra care to ensure the lotions and sticks we do carry are light and easy to wear. Our vetting process also ensures the sun protection products we offer have addressed the common sunscreen complaints you’ve likely had in the past, such as formulas being too heavy, rubbing off easily, carrying a strong smell, or causing breakouts. 

While we hope you now feel empowered to choose the right sunscreen for you, consider this your gentle reminder that picking a product is just the beginning, it’s important to wear it right too. For starters, sunscreen should be worn every day of the year, not just in the warmer months. Why? Because even when it’s cloudy outside, 80% of the sun’s rays still reach the earth. Plus, UV rays can travel through windows and are reflected by sand, water, snow, and ice. Another common mistake many people make is applying too little product. To correct this, try using the two-finger method: apply sunscreen to the length of your pointer and index finger, and use this amount (no less!) to cover an area like your face and neck. Lastly, spending too much time in the sun, neglecting to seek shade, and skipping reapplications can negate the hard work of your sunscreen. It’s important to be holistically sun smart this summer, and every day, to keep your skin youthful and healthy.