Sunscreen 101: Physical vs. Chemical Barriers Explained

Jump To Section:

Every day in Florida we step out into the world under the watchful gaze of the sun. While the sun is life giving, it also poses significant risks to our skin. There are many essentials in skincare, but using sunscreen is our greatest protection against the sun’s relentless ultraviolet (UV) onslaught. However, not all sunscreens are created equal, and understanding the nuances between chemical and physical barriers is crucial for optimal skin health.

Chemical sunscreens absorb UV rays and transform them into harmless heat. However, emerging research and skin health advocacy increasingly highlight the benefits of physical barrier sunscreens. These sunscreens, leveraging minerals like zinc oxide and titanium dioxide, act as a literal shield, reflecting UV rays away from the skin. At Glow Dermspa, we advocate the use of physical barrier sunscreens, not just for their efficacy but also for their gentler impact on the skin and the environment.

Among the plethora of options, two brands stand tall in our recommendation list: Alastin and EltaMD. These sunscreens are not only formulated with the skin-friendly minerals zinc and titanium but also embody the pinnacle of skincare innovation, offering broad-spectrum protection without compromising on comfort or cosmetic elegance. As we delve deeper into the world of sunscreens, let us guide you through the importance of choosing the right type, the distinct advantages of physical over chemical barriers, and why Alastin and EltaMD should be your go-to choices for safeguarding your skin against the sun’s rays.

Understanding Chemical vs. Physical Barrier Sunscreens

The world of sunscreens is divided primarily into two distinct types: chemical and physical barriers, each employing a unique mechanism to shield the skin from the sun’s ultraviolet (UV) radiation. This distinction is crucial for making informed choices about skin health and environmental impact.

Chemical Sunscreens: The Invisible Absorbers

Chemical sunscreens are formulated with organic (carbon-based) compounds, such as avobenzone, oxybenzone, octinoxate, and octocrylene. These compounds absorb UV radiation, converting it into heat, which is then released from the skin. The allure of chemical sunscreens lies in their lightweight, easily absorbed formulations, making them a favored choice for daily wear and cosmetic layering. However, concerns have been raised about potential skin sensitivities, hormonal disruptions, and environmental impacts, particularly the harm to coral reefs attributed to some chemical ingredients.

Physical (Mineral) Sunscreens: The Reflective Shields

In contrast, physical barrier sunscreens utilize natural minerals, primarily zinc oxide and titanium dioxide, to create a protective shield atop the skin. This shield reflects and scatters UV rays, preventing them from penetrating the skin. Unlike their chemical counterparts, physical sunscreens offer immediate protection upon application, are less likely to cause skin irritation or allergic reactions, and are considered safer for sensitive skin and the environment. Their broad-spectrum coverage effectively guards against both UVA (aging) and UVB (burning) rays, with zinc oxide being particularly noted for its comprehensive UVA protection.

The Benefits of Zinc Oxide and Titanium Dioxide

Zinc oxide and titanium dioxide stand out for their safety profile and efficacy. Zinc oxide is renowned for its ability to cover the entire spectrum of UVA and UVB rays, offering superior photo-stable protection that remains effective under prolonged sun exposure. Titanium dioxide complements this by providing robust UVB protection. Together, they form the foundation of physical sunscreens recommended by dermatologists and skincare experts for all skin types, including sensitive and acne-prone skin.

This exploration into the mechanisms of chemical and physical sunscreens illuminates the superiority of physical barriers in providing safe, effective, and environmentally friendly sun protection. As we proceed, the focus will shift to the benefits of physical barrier sunscreens, highlighting their unmatched ability to safeguard the skin against the sun’s harmful effects.

The Benefits of Physical Barrier Sunscreens

Physical barrier sunscreens, leveraging the protective powers of zinc oxide and titanium dioxide, offer a plethora of advantages over their chemical counterparts. These benefits not only extend to superior skin protection but also encompass environmental safety and suitability for sensitive skin types. Here, we explore why physical barrier sunscreens are the preferred choice for discerning skincare enthusiasts.

Broad-Spectrum Coverage

One of the standout features of physical sunscreens is their ability to provide broad-spectrum protection. Zinc oxide, in particular, is highly effective at shielding the skin from both UVA and UVB rays. UVA rays are known for their deep skin penetration, contributing to premature aging and skin cancer, while UVB rays are responsible for sunburn and surface damage. By reflecting and scattering these rays away from the skin, physical barrier sunscreens ensure comprehensive protection against the sun’s full spectrum of harmful effects.

Gentle on Sensitive Skin

Physical sunscreens are inherently gentler on the skin compared to chemical formulations. Since they sit on the skin’s surface and do not get absorbed, they are less likely to cause irritation, making them ideal for individuals with sensitive, reactive, or acne-prone skin. Moreover, zinc oxide and titanium dioxide are non-comedogenic, meaning they do not clog pores, further reducing the risk of acne outbreaks and skin irritations.

Environmentally Friendly

The environmental impact of sunscreen has become a growing concern, with research indicating that certain chemical sunscreen ingredients contribute to coral reef bleaching and aquatic toxicity. Physical barrier sunscreens, free from these harmful chemicals, are considered reef-safe and less damaging to marine ecosystems. Choosing a physical sunscreen not only protects your skin but also plays a part in preserving our planet’s precious coral reefs and aquatic life.

Stable and Effective Protection

Physical sunscreens offer stable and long-lasting protection under sun exposure. Unlike some chemical ingredients that can degrade and lose efficacy when exposed to sunlight, zinc oxide and titanium dioxide remain stable, providing consistent protection throughout the day. This stability ensures that the sunscreen continues to reflect harmful rays away from the skin without breaking down, offering peace of mind during prolonged outdoor activities.

The benefits of physical barrier sunscreens are clear: superior protection, gentleness on sensitive skin, environmental safety, and stable efficacy. These attributes make them the recommended choice for anyone seeking effective and responsible sun protection.

Spotlight on Alastin and EltaMD Sunscreens

In the vast sea of sun protection options, Alastin and EltaMD emerge as beacon brands, exemplifying the pinnacle of physical barrier sunscreen technology. These brands have distinguished themselves not only through their commitment to using zinc oxide and titanium dioxide but also in their dedication to formulating products that meet the needs of diverse skin types while ensuring environmental responsibility. Here, we shine a spotlight on what makes Alastin and EltaMD the preferred choices for discerning skincare enthusiasts.

Alastin Sunscreens: Innovation Meets Efficacy

Alastin Skincare is renowned for its cutting-edge approach to skincare, with sunscreens that epitomize the brand’s innovation. Their physical sunscreens are formulated with a high concentration of zinc oxide, providing broad-spectrum protection against UVA and UVB rays. What sets Alastin apart is the inclusion of proprietary ingredients designed to support the skin’s natural healing processes and enhance skin health. Their sunscreens not only protect against sun damage but also contribute to the skin’s overall rejuvenation, making them a favored choice for those looking to combine sun protection with anti-aging benefits.

EltaMD Sunscreens: Trusted Protection for Every Skin Type

EltaMD has established a sterling reputation for offering a wide range of sunscreen products tailored to various skin concerns, including acne-prone, sensitive, and rosacea-affected skin. Their formulations boast a blend of zinc oxide for broad-spectrum protection and additional ingredients like hyaluronic acid to hydrate and soothe the skin. EltaMD’s commitment to non-comedogenic, fragrance-free, and paraben-free formulas has made their sunscreens a staple in dermatologists’ recommendations. Their products are designed to be lightweight and wearable, making daily sun protection an effortless addition to any skincare routine.

Choosing Alastin and EltaMD: Beyond the Sunscreen

Opting for Alastin or EltaMD sunscreens goes beyond choosing a product; it’s a decision to invest in your skin’s long-term health and environmental sustainability. These brands’ formulations ensure that users receive the highest level of protection without compromising on skin comfort or contributing to ecological damage. By selecting Alastin or EltaMD, individuals can enjoy the outdoors with confidence, knowing their skin is shielded by products that align with the highest standards of safety, efficacy, and responsibility.

Choosing the Right Sunscreen for Your Skin Type

Navigating the vast array of sunscreen options can be daunting, especially when trying to match products with your specific skin type and concerns. The decision between Alastin, EltaMD, or any high-quality sunscreen should be informed not just by the brand’s reputation but also by how well the product aligns with your skin’s unique needs. Here’s a guide to selecting the right sunscreen, ensuring you get the most effective and comfortable protection.

How Your Skin Type Relates to Sunscreen

The first step in choosing the right sunscreen is understanding your skin type. Whether your skin is oily, dry, sensitive, or combination, there’s a sunscreen that caters to your specific needs.

For oily skin, look for lightweight, non-comedogenic formulas that won’t clog pores or exacerbate oiliness.

Dry skin types will benefit from sunscreens with added moisturizers, like hyaluronic acid or ceramides, to nourish the skin while providing protection.

Sensitive skin individuals should lean towards physical sunscreens with minimal ingredients to reduce the risk of irritation.

The Role of SPF in Sunscreen Effectiveness

SPF, or Sun Protection Factor, measures a sunscreen’s ability to protect against UVB rays, the primary cause of sunburn. While higher SPF values offer greater protection, it’s crucial to understand that the increase in protection is not linear. For example, SPF 30 blocks about 97% of UVB rays, while SPF 50 blocks about 98%. No sunscreen can block 100% of UV rays, so it’s essential to choose an SPF appropriate for your exposure level and reapply regularly, especially after swimming or sweating.

Tips for Sunscreen Application and Reapplication

For optimal protection, apply sunscreen generously about 15 minutes before sun exposure to allow for proper absorption. Most adults need about one ounce (enough to fill a shot glass) to fully cover the body. Don’t forget easily missed areas like the tops of the ears, back of the neck, and the feet. Reapplication is just as important as the initial application. Sunscreen should be reapplied at least every two hours, or more frequently if you’re swimming or sweating heavily.

Choosing the right sunscreen involves more than picking a brand; it requires considering your skin type, the SPF level, and application habits. By selecting a product that matches your skin’s needs and committing to diligent application and reapplication, you can enjoy the sun’s warmth without compromising your skin’s health. As we demystify common myths and misconceptions in the next section, we’ll further equip you with the knowledge needed to make informed sunscreen choices.

Common Myths and Misconceptions About Sunscreens

When it comes to sunscreen, misinformation abounds, leading to confusion and, sometimes, inadequate protection against the sun’s harmful effects. By dispelling some of the most common myths and misconceptions about sunscreens, we aim to empower you with accurate information to make informed decisions about your sun protection strategy.

Myth 1: Chemical Sunscreens Are Unsafe

Concerns about chemical sunscreens often arise due to studies on their absorption into the skin and potential effects on the environment. While some chemical filters have raised questions, it’s essential to recognize that the FDA continues to evaluate the safety and efficacy of sunscreen ingredients. Physical sunscreens with zinc oxide and titanium dioxide are generally recommended for those with sensitive skin or environmental concerns, but many chemical sunscreens are safe and effective when used as directed.

Myth 2: Higher SPF Means Much Better Protection

While higher SPF sunscreens do offer more protection, the difference becomes marginal beyond a certain point. SPF 30 blocks approximately 97% of UVB rays, whereas SPF 50 blocks about 98%. No sunscreen can block 100% of the sun’s rays, and high SPF values can lead to a false sense of security, potentially resulting in less frequent reapplication. The key is to choose a broad-spectrum sunscreen with an SPF appropriate for your activity level and exposure and to reapply it regularly.

Myth 3: I Don’t Need Sunscreen on Cloudy Days or Indoors

UV rays can penetrate clouds and windows, meaning your skin is at risk of UV exposure even on overcast days or when indoors near windows. UVA rays, in particular, are notorious for their ability to pass through clouds and glass, contributing to premature aging and skin cancer risk. Daily sunscreen application, regardless of the weather or indoor status, is crucial for comprehensive skin protection.

Myth 4: Darker Skin Tones Don’t Need Sunscreen

While melanin in darker skin tones does provide some natural protection against UV radiation, it’s not enough to prevent skin damage. People of all skin colors can develop skin cancer and experience premature aging due to sun exposure. Broad-spectrum sunscreen is essential for everyone, regardless of skin tone, to protect against UVA and UVB rays.

Myth 5: Physical Sunscreens Leave a White Cast and Are Unpleasant to Use

Modern formulations of physical sunscreens have come a long way in addressing the aesthetic concerns historically associated with these products. Brands like Alastin and EltaMD offer physical barrier sunscreens that blend seamlessly into the skin without leaving a white cast, making them suitable for all skin tones and types. Advances in formulation technology have resulted in lightweight, non-greasy products that provide effective protection without compromising on cosmetic elegance.

Armed with the truth about sunscreens, you can navigate the sea of options with confidence, ensuring your skin is protected with the best possible care.

Sunscreen Application Tips for Optimal Protection

Applying sunscreen correctly is just as crucial as choosing the right product. Even the best sunscreens can only offer their full protective benefits when used properly. Here are essential tips to ensure your sunscreen application maximizes skin protection, making sun care an effective and seamless part of your daily routine.

Generous and Even Application

One of the most common mistakes is applying too little sunscreen. For full-body coverage, most adults need about one ounce of sunscreen — roughly the amount that can fit in a shot glass. Ensure even coverage by applying a thick layer to all exposed skin, including often-missed spots like the tops of the ears, back of the neck, and the feet.

Timing Is Everything

Sunscreen should be applied to dry skin 15 to 30 minutes before sun exposure. This allows the sunscreen to bind to the skin and begin working by the time you step outside. For daily use, incorporate sunscreen into your morning skincare routine to ensure you’re protected right from the start of the day.

Reapplication Is Key

Sunscreen wears off over time due to sweating, swimming, and towel drying. Reapply at least every two hours, and immediately after swimming or excessive sweating, regardless of the SPF or water-resistance rating. Remember, no sunscreen is entirely waterproof or sweatproof; reapplication is essential for continued protection.

Don’t Forget Lip Protection

The lips are vulnerable to sunburn and skin cancer, yet they’re often overlooked in sun protection efforts. Use a lip balm with SPF 30 or higher and reapply it regularly, especially if you’re eating, drinking, or swimming.

Consider the Season and Environment

UV exposure can vary significantly depending on the season, location, and time of day. Sun protection is crucial year-round, not just during summer, as UV rays can penetrate clouds and reflect off snow, water, and sand, increasing exposure. Adjust your sunscreen use accordingly, especially during outdoor activities or in environments with higher UV reflection.

Embrace Additional Sun Protection Measures

While sunscreen is a critical tool in sun protection, it’s most effective when combined with other measures. Seek shade during peak UV hours (10 a.m. to 4 p.m.), wear protective clothing, sunglasses with UV protection, and wide-brimmed hats. These additional layers of defense can significantly reduce your overall UV exposure.

Adhering to these sunscreen application tips will enhance your skin’s defense against UV damage, supporting a healthy, cancer-free complexion. As we conclude our discussion, we’ll wrap up with key takeaways and a reminder of the importance of comprehensive sun protection for maintaining vibrant, healthy skin.

FAQ: Sun Protection and Sunscreen Choices

Discover the essentials of effective sun protection and learn about the top sunscreen recommendations from Glow Dermspa to keep your skin safe and healthy under the Florida sun.

What is the difference between chemical and physical barrier sunscreens?
Chemical sunscreens absorb UV rays and convert them into heat, while physical barrier sunscreens, such as those containing zinc oxide and titanium dioxide, reflect UV rays away from the skin. We recommend physical sunscreens for their broad-spectrum protection and gentler impact on both skin and the environment.

Why does Glow Dermspa recommend Alastin and EltaMD sunscreens?
Alastin and EltaMD sunscreens are favored for their use of skin-friendly minerals, such as zinc oxide and titanium dioxide, which offer broad-spectrum UV protection. These brands are known for their lightweight formulas that are comfortable for daily wear and do not leave a white residue, making them suitable for all skin types, including sensitive skin.

Are physical sunscreens suitable for all skin types?
Yes, physical sunscreens are suitable for all skin types, including sensitive, acne-prone, and rosacea-affected skin. They are particularly recommended for those with sensitive skin because they are less likely to cause irritation or allergic reactions compared to chemical sunscreens.

How often should sunscreen be reapplied?
Sunscreen should be reapplied every two hours when outdoors, and immediately after swimming, sweating, or towel drying. Even on cloudy days or when indoors near windows, it’s important to apply sunscreen to protect against UVA rays that can penetrate glass and clouds.

What are the benefits of using sunscreens like Alastin and EltaMD?
Sunscreens from Alastin and EltaMD not only protect against sunburn and long-term UV damage but also enhance skin health by incorporating ingredients that support skin barrier function and hydration. Their non-comedogenic formulas are especially beneficial for maintaining clear, healthy skin.

Can wearing sunscreen prevent skin aging?
Yes, regular use of sunscreen can significantly prevent premature skin aging caused by the sun, such as wrinkles, fine lines, and sun spots. Broad-spectrum sunscreens protect against both UVA and UVB rays, which contribute to skin aging and damage.

Is it necessary to wear sunscreen even if I don’t spend a lot of time outdoors?
Yes, wearing sunscreen daily is crucial as UVA rays, which contribute to skin aging and cancer, can penetrate windows and affect your skin even when you’re indoors or in a car.

What should I look for in a sunscreen if I have acne-prone skin?
For acne-prone skin, look for sunscreens that are oil-free, non-comedogenic, and labeled as suitable for sensitive skin. Physical sunscreens are often preferred as they are less likely to clog pores or cause breakouts.

How can I choose the right SPF number in a sunscreen?
Choose a sunscreen with at least SPF 30 for daily use, which blocks about 97% of UVB rays. For extended outdoor activities, especially in Florida’s sunny climate, SPF 50 or higher can provide additional protection.

Are there any environmental concerns associated with sunscreen use?
Yes, certain chemical sunscreen ingredients have been linked to coral reef damage and other environmental issues. Physical sunscreens with zinc oxide and titanium dioxide are generally considered to be more environmentally friendly options.


Embracing the sun’s warmth and vitality comes with the responsibility of safeguarding our skin from its potentially harmful effects. By understanding the nuances of sunscreen—chemical versus physical barriers, the benefits of physical barrier sunscreens—gives us a more holistic view of sun protection, and its role as an integral part of skin health and wellness.

For residents of Lakewood Ranch, Bradenton, Sarasota and Tampa Florida, the quest for the perfect sunscreen is more than a precaution—it’s a lifestyle. The sun graces us with its presence year-round, demanding a steadfast commitment to skin protection. We understand the importance of this commitment. We at Glow Dermspa are here to guide you through the selection of high-quality sunscreen products, like Alastin and EltaMD, ensuring you enjoy the sun’s embrace safely and confidently.

We invite you to visit Glow Dermspa, where our experts are ready to assist you in finding the sunscreen solution that aligns with your skin type, concerns, and aesthetic preferences. Book an appointment today and embark on a journey to radiant, protected skin under the Florida sun.

Share This Article:

Join the Glow Newsletter

Be the first to know


Related Articles

Explore by Category

Latest Instagram Posts


Meet Our Providers

Melissa Beachy
Melissa Beachy, PA - C Director & Master Injector
Lacy Rogers
Lacy Rogers Aesthetician
Nina Vital Millard, PA-C Master Injector
Dr. Dana Ellis
Dr. Dana Ellis Board Certified Dermatologist

Latest Reviews

Michelle SchillerMichelle Schiller ★★★★★ As always Excellent customer service. Melissa is highly knowledgeable and skilled at injectables.Jesse VanceJesse Vance ★★★★★ Great team Melissa has assembled. The tacos state of the art and the experience Melissa has is tremendous. Would definitely recommend.Debbie OkeefeDebbie Okeefe ★★★★★ Amazing service in a 5 star spa setting!js_loader