What to Look for in a Sunscreen: Expert Tips from McKay Dermatology & MedSpa
Located in sunny Stuart, Florida, one of the most common questions we get here at McKay Dermatology & MedSpa is: "What’s the best sunscreen?" With so many options on the market—and plenty of myths floating around—it can be hard to know what to trust.
We’re here to break it down for you with dermatologist-approved sunscreen advice, helpful tips, and some of our favorite in-office sun block products from brands like Alastin and ISDIN. Let’s dive into what you really need to know.
Key Elements to Look for in a Sunscreen
When choosing a sunscreen, make sure the label checks these boxes:
1. Broad-Spectrum Protection
Always choose a broad-spectrum sunscreen. This means it protects against both UVA rays (which cause premature aging) and UVB rays (which cause sunburn).
2. SPF 30 or Higher
For everyday use, we recommend a minimum of SPF 30. If you’ll be spending extended time outdoors—especially in Florida’s sunny climate—go for SPF 50 or higher.
Ingredients to Avoid
Some chemical sunscreen ingredients have raised red flags due to their potential health and environmental impacts. When shopping for sunscreen, consider avoiding:
Oxybenzone – a chemical filter that may disrupt hormones and has been linked in some studies to cell damage, hormone disruption and potential cancer risk. It's also one of the main culprits in coral reef destruction.
Octinoxate – another UV filter suspected of hormone disruption and environmental harm.
Retinyl Palmitate (Vitamin A) – when used in sunscreen, it may break down under UV exposure and create free radicals that could contribute to skin damage and potentially accelerate the development of skin tumors and lesions.
Fragrance – often made from undisclosed chemical blends that can trigger irritation and allergic reactions, especially on sun-exposed skin.
Suns – preservatives and softeners that may interfere with hormone function and have also been studied for links to cancer.
For a safer choice, opt for mineral sunscreens that use zinc oxide or titanium dioxide, which sit on top of the skin to reflect UV rays and are less likely to absorb into the bloodstream.
How Often Should You Reapply Sunscreen?
Reapplication is just as important as picking the right product. You should reapply sunscreen:
· Every 2 hours during sun exposure.
· Immediately after swimming or sweating.
· More often if using spray sunscreens, which can rub off or evaporate more easily.
If you're headed to the pool, lake, or ocean, choose a water-resistant sunscreen—and still reapply every 80 minutes for best protection.
Truth or Myth: The higher the SPF, the longer you can go before reapplying
Myth! The higher levels of SPF only offer slightly more protection. For example, SPF 30 blocks about 97% of UVB rays, SPF 50 blocks about 98%, and SPF 100 blocks about 99%. No sunscreen blocks 100% of rays, and higher SPF can sometimes give a false sense of security, causing people to reapply less often (which is when damage happens!).
Our Favorite Sunscreens (Available In-Office)
We’ve hand-selected a few sunscreen products we love and trust—available right here at McKay Dermatology & MedSpa in Stuart, Florida.
ISDIN Eryfotona Actinica SPF 50+
This ultralight mineral sunscreen is not only broad-spectrum and water-resistant, but it also includes DNA Repairsomes—enzymes that help repair existing sun damage. Perfect for daily wear and especially beneficial for patients with a history of sun damage or pre-cancers.
ISDIN Eryfotona Ageless Tinted Mineral SPF 50
This powerhouse formula offers more than just sun protection—it’s a multitasking anti-aging sunscreen that’s tinted to double as your foundation. Eryfotona Ageless combines broad-spectrum SPF 50 with DNA Repairsomes, peptides, and antioxidants like vitamin E to help prevent and repair visible signs of photoaging. The subtle universal tint helps even out skin tone, making it a great daily option for anyone wanting sun protection with added beauty benefits. Lightweight, non-greasy, and ideal for mature or sun-damaged skin, it’s one of our top recommendations—available for purchase in-office at McKay Dermatology & MedSpa in Stuart, Florida.
Alastin HydraTint Pro Mineral Broad Spectrum SPF 36
A staff and patient favorite! This mineral sunscreen has a gorgeous tint that blends beautifully into most skin tones, offering lightweight coverage and a healthy glow. It’s fragrance-free, non-comedogenic, and great for everyday wear, even under makeup.
Alastin SilkSHIELD All Mineral SPF 30
Designed for even the most sensitive post-procedure skin, this silky formula provides powerful protection with zinc oxide and TriHex Technology® to support the skin’s natural barrier and recovery.
Sun Protection from the Inside Out
Did you know there are supplements that can provide additional UV protection? Heliocare Advanced daily supplement is a favorite for anyone looking to boost their skin’s natural defense against UV damage—especially those with sun-sensitive skin, a history of skin cancer, melasma, or frequent sun exposure. Powered by Fernblock® PLE technology and nicotinamide (vitamin B3), it helps protect against free radicals and supports skin resilience. Heliocare Advanced is the perfect complement to sunscreen (not a replacement for topical sun block).
Protect Your Skin Year-Round
Whether you’re heading to the beach or just running errands around the Treasure Coast, daily sunscreen is non-negotiable. Remember, UV rays are present even on cloudy days—and even when you're indoors near windows or in the car.
Want help finding the right sunscreen for your skin type or lifestyle? Stop by McKay Dermatology & MedSpa and chat with our knowledgeable team. Our curated selection of medical-grade sunscreens from ISDIN and Alastin are available for purchase in-office. Take 20% off all sunscreen purchases through the end of May, 2025.