By Dr. Alexsia Priolo

It’s that time of year where you’re likely donning lighter clothes , spending time outside, and filling up on vitamin D. Therefore, finding a sunscreen that works for you is incredibly important because it’s one of the necessary ingredients to protect your skin.

Here’s what you need to know about choosing your perfect sunscreen:

SPF RATING

SPF stands for sun protection factor and generally refers to the sunscreen’s ability to deflect UVB rays. The rating is calculated by comparing the amount of time needed to burn sunscreen-protected skin versus unprotected skin. It’s important to know that no sunscreen can completely block the sun’s rays, which is why the term sunblock is no longer used.

High SPF products tend to convince users into staying into the sun longer and overexposing themselves to UVA and UVB rays, but the protection is negligible. A SPF of 15 confers about 93% of protection while an SPF of 50 confers about 97-99% of protection.

BROAD SPECTRUM

This means that the sunscreen protects against UVA and UVB rays by providing a physical or chemical barrier that absorbs or reflects UV rays before it can damage the skin. UVA rays penetrate deep into the dermis and may cause premature aging. While UVB rays burn the superficial layers of the skin and may develop into skin cancer.

ACTIVE INGREDIENTS

There are two main types of sunscreens: mineral and chemical.

Mineral (physical) sunscreens often form a white film on the top of the skin and the active ingredients are often zinc oxide and titanium dioxide. To get the most UVA and UVB protection, look for a product that has more than 20% of zinc. Titanium dioxide does not provide enough UVA protection. Studies have shown that zinc and titanium do not significantly penetrate the skin in large amounts, unlike chemical sunscreens.

Mineral sunscreens have the ‘non-nano’ claim. Zinc and titanium are in the form of nanoparticles, these sizes vary among manufacturers, but are all considered nanoparticles. There is no evidence that zinc crosses the skin in significant amounts. However, there is an inhalation concern for mineral sunscreens as they may cause lung damage. If you choose to use a spray, cover the mouth of the person as you spray towards it. To protect their face, spray sunscreen on your hands and apply it to the face directly.

Chemical (non-mineral) sunscreens often soak into the skin, without leaving a thin film. Ingredients include avobenzone, oxybenzone, octocrylene and emcamsule. Studies have shown that oxybenzone can be found in breast milk, amniotic fluid, urine and blood. There is a potential link between oxybenzone and lower testosterone levels in adolescent boys, hormonal changes in men, and shorter pregnancies and disrupted birth weights in babies.

WATER OR SWEAT RESISTANT

There is no such thing as waterproof sunscreen, all sunscreens eventually wash off. When your sunscreen gives you a resistant time (eg. 40 minutes), you must reapply it according to that time, otherwise sunscreens should be reapplied every two hours in normal conditions.

SUN SAFETY TIPS

1. Off hours – Plan around the sun: early morning or late afternoons, when the sun isn’t so high in the sky. Avoid going outside between 11am to 4 pm.

2. UV Index – Check it before you plan your outdoor activities for the day using your weather app on your phone or the Weather Network.

3. Clothes – Wear hats, shirts, pants, shorts to shield your skin. If you can see your hand through your shirt, it may be too sheer and not provide adequate protection. Cotton and linen are breathable fabrics.

4. Shade – Find or make shade, keep your infants in the shade.

5. Sunglasses – Use this functional accessory to protect your eyes from UV rays.

Applying Sunscreen

Apply 15 minutes before going outside (although it’s thought that mineral sunscreens will work right away as they don’t penetrate into the skin). Use enough sunscreen to cover your entire face and body (avoiding the eyes and mouth). Reapply at least every two hours, and more often if you’re swimming or sweating.

Frequently forgotten spots

-Ears
-Nose
-Lips
-Back of Neck
-Hands
-Tops of feet
-Along the hairline
-Areas of the head exposed by balding or thinning hair

References:

Ewg.org. (2019). EWG’s 2019 Guide to Safer Sunscreens. [online] Available at: https://www.ewg.org/sunscreen/.

Matta, M., Zusterzeel, R., Pilli, N., Patel, V., Volpe, D., Florian, J., Oh, L., Bashaw, E., Zineh, I., Sanabria, C., Kemp, S., Godfrey, A., Adah, S., Coelho, S., Wang, J., Furlong, L., Ganley, C., Michele, T. and Strauss, D. (2019). Effect of Sunscreen Application Under Maximal Use Conditions on Plasma Concentration of Sunscreen Active Ingredients. JAMA, 321(21), p.2082.