All Your Sunscreen Questions, Answered

Ask any dermatologist for their top skincare tip and you’re likely to receive the same answer: “Wear sunscreen — every single day.” But for many of us, this advice is easier said than done. It can be difficult to find a formula that works for your skin, doesn’t irritate your eyes, and won’t leave you feeling like a sticky mess or Casper the ghost. 

According to the 2020 RealSelf Sun Safety Report, nearly two-thirds of Americans use anti-aging skincare products as part of their regimen, but a mere 11 percent wear sunscreen every day and 46 percent never wear it at all. 

Ilanit Samuels, PA-C, with Baumann Cosmetic Dermatology, Miami, Fla., says, “I give my patients the analogy of buying an expensive couture dress. You’d never put a $5,000 dress in the washing machine. If you come in for an anti-aging procedure and you’re not using a high-quality sunscreen like ALASTIN HydraTint Pro Mineral Broad Spectrum Sunscreen SPF 36 or  SilkSHIELD® All Mineral Sunscreen SPF 30 with TriHex Technology®, you’re flushing your money down the toilet. You need to continue to treat and care for your skin in order to safeguard what you spend.”

Here’s how to navigate your sunscreen questions so you can reap the benefits of daily use and protect your skin for years to come. 

What are the benefits of wearing sunscreen every day? 

When used as directed, daily sunscreen use is shown to decrease your risk of skin cancer and precancers. According to the Skin Cancer Foundation, regular application can reduce your risk of squamous cell carcinoma by roughly 40 percent, while lowering your risk of melanoma by 50 percent.  

The sun is also responsible for 90 percent(!) of premature skin aging. Think wrinkles and fine lines, sagging skin, age spots, hyperpigmentation, and rough texture.

By blocking the sun’s harmful rays, sunscreen helps to keep your skin looking its best (and its youngest), while warding off all visible signs of aging. 

What’s the difference between UVA and UVB light? 

When shopping for sunscreen, experts agree that you should look for formulas labeled “broad spectrum.” Broad-spectrum sunscreen is proven to block both UVA and UVB light. Both of these types of light are forms of ultraviolet radiation, part of the sun’s natural energy. UVA light has a longer wavelength that penetrates the skin more deeply and is connected to premature skin aging, while UVB light has a shorter wavelength and is the type that may cause your skin to burn. Both UVA and UVB damage the DNA in your skin cells.

What’s the difference between mineral and chemical sunscreen? 

Mineral sunscreen uses particles like titanium dioxide and zinc oxide to reflect UV radiation from the skin, providing a physical barrier to shield the sun’s harmful rays. Chemical sunscreen, on the other hand, employs certain chemical filters like oxybenzone and octisalate that absorb the rays (instead of deflecting them), causing a chemical reaction that releases the energy as heat.

Many people with sensitive skin prefer mineral sunscreens as they are less likely to irritate the eyes and skin. Additionally, mineral sunscreens naturally offer broad-spectrum protection, thereby helping to ward off both skin cancer and premature skin aging. The reason why some people avoid mineral sunscreen is that many formulas leave a white, chalky look. ALASTIN’s formulas, however, provide all the benefits of all-mineral sunscreens with zero white cast. 

HydraTint Pro Mineral Broad Spectrum Sunscreen SPF 36 includes a glowy tint that works with most skin tones, while the untinted SilkSHIELD® All Mineral Sunscreen SPF 30 with TriHex Technology® glides smoothly over the skin with an invisible finish. Both are formulated with non-nano-zinc oxide, a well-proven mineral blocker that makes it easy to wear these sunscreens every day. 

What is SPF exactly? 

Contrary to popular belief, the level of SPF or “sun protection factor” in your sunscreen is not directly linked to the amount of time you are protected for — SPF 15 does not mean you need to reapply after 15 minutes. Instead, the FDA describes SPF as “a measure of how much solar energy (UV radiation is required to produce sunburn on protected skin (i.e., in the presence of sunscreen) relative to the amount of solar energy required to produce sunburn on unprotected skin.” 

Solar energy absorption can differ depending on how fair your skin is and where the sun is in the sky. When it comes to SPF, the one rule of thumb most dermatologists agree on is that you should look for a sunscreen with an SPF rating of 30 or higher, which blocks 97 percent of the sun’s rays. Higher levels of SPFs don’t make a marked difference in terms of protection. For example, SPF 50 blocks 98 percent.  HydraTint Sunscreen has an SPF of 36 and SilkSHIELD® has an SPF of 30 — both fitting the bill. 

How much sunscreen is enough? 

For sunscreen to work properly, you need to use an adequate amount to cover your skin. For the face, that’s 0.4 fluid ounces. You can also visualize that as  ⅓ teaspoon or a nickel-sized dollop. (If you are using HydraTint, you’ll want a full two pumps). 

For the body, aim to slather yourself with 1.5 fluid ounces. That’s the amount it would take to fill up a standard-sized shot glass. 

How should I layer sunscreen with moisturizer? 

According to John Hopkins Medicine, as long as you use the appropriate amount of sunscreen, it doesn’t matter if you apply sunscreen before or after your moisturizer. However, most people prefer to use sunscreen as the final layer of their skincare, the “icing on the cake,” right before you apply any makeup. Using sunscreen as the final step will ensure you don’t inadvertently wipe it off while applying other serums or moisturizers, and your other products can also help prep the skin to ensure your sunscreen doesn’t cake. 

What’s the best way to apply sunscreen with makeup? 

After you layer your skincare and use your sunscreen, you can go ahead and apply your makeup. A word of warning: Do not rely on the SPF in your foundation to provide ample coverage. Experts agree it’s nearly impossible to apply enough foundation to get the protection you need. 

Depending on the level of makeup coverage you’re after, you may want to use a tinted sunscreen like HydraTint. The formula delivers a soft glow thanks to an iron oxide tint that works for most skin tones and can be used in place of makeup. If the tint is too light or dark for your skin tone, you may prefer to use a translucent formula like SilkSHIELD® instead. Both HydraTint and SilkSHIELD® can also be used as a primer as they are formulated to play well with foundation and prevent pilling. 

How often do I need to apply sunscreen? 

Sunscreen should be reapplied throughout the day — especially if you’re out in the sun. Get into the habit of applying sunscreen every single morning, even if you’re planning to be inside. UV light can damage your skin through the window of an office or car. After your first application, reapply as needed. According to John Hopkins, you may not need to reapply if you’re indoors all day, but if you are outside you should reapply every two hours. You’ll also want to re-up after swimming or exercising.

Does sunscreen have any other benefits? 

Sunscreen has one critical job: Protecting your skin from the sun’s harmful rays. Beyond this, some science-backed formulations do have added perks. For example, HydraTint provides long-lasting hydration, powerful antioxidants that help protect the skin from pollution, IR rays, and blue light — all while delivering a soft glowing tint that evens and brightens most skin tones. SilkSHIELD® also provides protection from IR rays, pollution, and blue light, as well as anti-aging benefits that last long after sunset thanks to an exclusive blend of peptides

Remember: When it comes to sunscreen, the most important advice is to find a formula you love so you’ll feel motivated to use it every single day — and reap the benefits of younger-looking skin for decades to come. 



1Phillips, Madison. “RealSelf Report: 62% of Americans Use Anti-Aging Products Daily, But Only 11% Wear Sunscreen Daily.” (2020, May 1). RealSelf.
2Halpern, A, Marghoob, A, & Reiter, O. “Melanoma Overview.” (2022, January 1). Skin Cancer Foundation.
3Chien, A & Jacobe, H. “UV Radiation & Your Skin.” (2021, August 1). Skin Cancer Foundation.
4Timmons, Jessica. “What’s the Difference Between Physical and Chemical Sunscreen?” (2022, February 3). Healthline.
5“How to Choose Your Sunscreen.” (2019, June 11). Penn Medicine.
6 “Sun Protection Factor (SPF).” (2017, July 14). U.S. Food & Drug Administration.
7Taglia, Lauren. “Quick Dose: How Much SPF Do You Really Need?” Northwestern Medicine.
Mayer, Beth Ann. “Exactly How Much Sunscreen Should You Use On Your Face?” (2021, August 9). Healthline.
9Chein, Anna Lien-Lun. “Sunscreen and Your Morning Routine” John Hopkins Medicine.
Wadyka, Sally. “Will Moisturizers With SPF Protect Your Skin?” (2019, April 3). Consumer Reports.
11Chein, Anna Lien-Lun. “Sunscreen and Your Morning Routine” John Hopkins Medicine.

Article Reviewed by Wendy Johnson
Wendy Johnson

Vice President, Marketing

Wendy Johnson brings to Alastin Skincare over 22 years of pharmaceutical, biotechnology, and aesthetics industry experience in various sales, training, marketing and thought leader development roles.

After spending 10 years in gastroenterology at Tap Pharmaceuticals and Prometheus Laboratories, with sales and marketing oversight for in-line and pre-launch products, Mrs. Johnson transitioned to an aesthetic career at SkinMedica in 2004. While there, she was responsible for marketing one of the top 2 branded prescription hydroquinones, launching a leading branded low potency steroid, and oversight of the acne franchise line extensions.

In 2010, Wendy joined Merz North America where she developed and managed the Physician Relations department in support of injectable, topical and device business units under Medical Affairs, before transitioning into managing a Regional Aesthetics Marketing team.

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