Ask Dr. Macrene:What is the best SPF Number to use?

During our summer event, we sat with Ivan Pol and Dr. Macrene to speak on best ways to combat sun damage, how to shop for SPF and more. 

Sun exposure is one of the leading causes of premature skin aging and skin cancer. While sunscreen and protective clothing remain essential, modern dermatology has introduced advanced treatments like photodynamic therapy (PDT)—a powerful way to repair sun damage and prevent precancerous cells from turning into skin cancer.

What Is Photodynamic Therapy?

Photodynamic therapy is considered the most advanced dermatology treatment for sun damage and skin cancer prevention. Here’s how it works:

  1. A light-sensitive solution is applied to an area such as the face, scalp, chest, or arms.

  2. This solution binds specifically to precancerous cells.

  3. Light is then used to activate the solution, selectively targeting and destroying damaged cells while sparing healthy skin.

The result? A field treatment that clears away sun damage and dramatically reduces the risk of skin cancer developing later.

Why Sun Protection Still Matters

Even with treatments like PDT, daily sun protection is non-negotiable. Cumulative exposure over a lifetime increases your risk. Dermatologists call this the multi-hit hypothesis—the more “hits” of sun damage you take, the higher the chance a precancerous cell mutates into cancer.

That’s why experts recommend:

  • Avoiding peak sun hours (10 AM–4 PM).

  • Seeking natural coverage like trees or shade when outdoors.

  • Wearing sun-protective clothing and wide-brim hats.

  • Using sunscreen daily—not just when it’s sunny.

What is the best SPF Number to use?

Dr Macrene says, "The higher the number, the better. I am a huge proponent of SPF 100 for two main reasons: One, everybody is under-applying their sunscreen, sometimes by 50% because if you put on the suggested amount you’ll experience a white cast. But if you are under-applying you’re only getting an SPF of 50. 
 
Secondly, every two hours you get a degradation of the sunscreen. If you started with SPF 30, after two hours you’re at 15. In conclusion, I’d recommend SPF 50. But when I get my hands on SPF 100, I prefer using that.”

Smart Sun Habits Beyond Sunscreen

Sunscreen is just one part of the equation. To minimize damage:

  • Plan outdoor activities in the late afternoon or early evening.

  • Wear UV-blocking clothing and reapply sunscreen often.

  • Be cautious around reflective surfaces like water, sand, and concrete, which intensify exposure.

  • Remember that face and scalp are high-risk zones, especially for swimmers and athletes.

The Bottom Line: Prevention + Innovation = Healthy Skin

Protecting your skin is about combining advanced dermatology treatments like photodynamic therapy with everyday protective habits. By clearing away precancerous cells and reinforcing your natural defenses with sunscreen and sun-smart living, you dramatically reduce your risk of skin cancer while keeping your skin healthy and youthful.

Watch the full video here.

 

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