Sunscreen 101: Everything you need to know about using SPF

Sunscreen 101: Everything you need to know about using SPF

One skincare step that is often overlooked is using SPF in your daily routine. Whether you're out in the sun or indoors, a good sunscreen is your skin's best friend. Here’s everything you need to know about using SPF and why it’s important to start using it.

What Is SPF?

SPF measures a sunscreen's ability to protect against UVB and UVA rays. The SPF number indicates how much longer you can stay in the sun without burning compared to not wearing sunscreen. For example, if your skin normally starts to redden after 10 minutes in the sun, an SPF 30 sunscreen theoretically allows you to stay in the sun 30 times longer without burning. However, it's important to remember that SPF isn't a guarantee—it needs to be applied and reapplied correctly. 

SPF products vary in strength, usually ranging from SPF 15 to SPF 100. Higher SPF numbers offer more protection, but the difference isn't as significant as you might think. While SPF 30 blocks around 97% of UVB rays, SPF 50 blocks about 98%, and SPF 100 blocks 99%. 

UV Rays and Their Impact

UV rays are the invisible enemy when it comes to skin health. There are two main types of harmful UV rays—UVA and UVB. UVA rays penetrate deep into the skin, leading to premature aging and contributing to skin cancer risk. They are present throughout the year, regardless of weather changes. This is why daily SPF application is important even on cloudy days. 

UVB rays are responsible for sunburn and play a key role in developing skin cancer. Unlike UVA rays, UVB intensity fluctuates based on factors like the sun's strength during the summer months or reflections from surfaces such as water or snow in the winter. Both UVA and UVB rays cause damage that leads to skin cancer. Therefore, choosing a broad-spectrum sunscreen that offers protection against both is essential for optimal skin health.

Choosing the Right SPF for Your Skin

With so many SPFs to choose from, it’s important to pick the right one for your skin. Here are some things to know when choosing sun protection. 

First, consider your skin type. Fair skin that burns easily requires higher SPF while darker skin⎯ which has more melanin, may manage with lower SPF. However, it’s recommended to use SPF 30 or higher for everyone to ensure sufficient protection. SPF 30 provides broad-spectrum coverage and blocks about 97% of UVB rays, which makes it ideal for everyday use—especially when reapplied throughout the day.

Next, what activities do you do? If you're swimming or sweating, opt for water-resistant sunscreens. These products stay effective for longer, but still need to be reapplied according to the time stated on the packaging. 

Do you have any skin sensitivities? Some sunscreens contain ingredients that might irritate sensitive skin. Mineral-based sunscreens containing zinc oxide or titanium dioxide are recommended for people with sensitive or reactive skin because they sit on the skin's surface rather than being absorbed, which reduces the likelihood of irritation. These ingredients are also less likely to cause allergic reactions compared to some chemical sunscreen ingredients.

Why You Need To Reapply Sunscreen

Applying sunscreen once in the morning isn't enough. To maintain protection, you need to reapply throughout the day. For maximum effectiveness, sunscreen should be reapplied every two hours. If you're swimming or sweating heavily, reapply immediately after drying off. This routine may seem cumbersome, but it's necessary for avoiding sun damage. Remember, SPF isn't just for beach days. Incorporate it into your everyday routine and reapply as needed based on your activities and exposure.

How to Apply SPF Properly

Applying SPF correctly ensures you’re fully protected. Here are application tips:

  • Use enough sunscreen to cover all exposed areas. The average adult needs about one ounce for full-body coverage. 
  • Apply SPF 15 to 30 minutes before sun exposure to give your skin time to absorb it
  • Make sure to cover often-missed areas, like the ears, neck, and feet. 
  • Don't forget about lip protection. Use lip balm with SPF to protect your lips from UV damage.

Benefits Of SPF Beyond Sun Protection

While sun protection is the primary function of SPF, it offers additional benefits that contribute to overall skin health and helps maintain a youthful complexion over time. It helps prevent premature aging by protecting against wrinkles and fine lines caused by UV exposure. Sunscreen also reduces the risk of hyperpigmentation which can lead to uneven skin tone and dark spots. SPF supports overall skin health by minimizing the risk of skin cancer.

Frequently Asked Questions (FAQs)

  1. How Do I Add SPF Into My Skincare Routine? You should use sunscreen after cleansing and moisturizing in the morning. Apply a broad-spectrum sunscreen with at least SPF 30 and wait a few minutes for it to absorb before applying makeup. Many makeup products like foundations, now include SPF, however, they often don't offer adequate protection alone, so use them alongside a dedicated sunscreen. 
  2. What Ingredients Should I Look For In SPF? When choosing an SPF, look for zinc oxide and titanium dioxide if you have sensitive or acne-prone skin, as these mineral-based ingredients sit on the skin’s surface to reflect UV rays and are less likely to cause irritation. For broad-spectrum protection, avobenzone is effective at absorbing UVA rays that contribute to skin aging. Octinoxate and octocrylene are also common in sunscreens and work well for general outdoor use, though they may not be ideal for sensitive skin types.
  3. What SPF products does Sarah recommend? For our sunscreen and SPF recommendations, visit here.