As summer quickly approaches and we begin spending more time outdoors, I thought this would be a good time to address ALL-THINGS related to sunscreen. With so many products available, it’s confusing for consumers to know which type of sunscreen product to use, how much SPF to apply, and how often you should re-apply.
What is the difference between Physical & Chemical SPF?
- Made with active mineral ingredients like zinc oxide and titanium dioxide
- Works by deflecting the sun’s rays
- Sits on top of the skin like armor and prevents the sun’s rays from being absorbed into the skin
- Typically referred to as “physical blockers”
- Made with carbon-based compounds like oxybenzone, avobenzone, octisalate, and octinoxate
- Works by absorbing the sun’s rays, converting them into heat and then releases heat from the skin
- Prevents the sun’s rays from penetrating the skin
- Typically referred to as chemical absorbers
What are the Pros and Cons of Physical vs. Chemical SPF?
Physical Sunscreen Pros:
- Offers protection against both UVA and UVB rays (it’s naturally broad-spectrum)
- Protects from the sun as soon as it’s applied, no wait needed for it to take effect
- Lasts longer than chemical sunscreen when exposed to direct UV light (but NOT when doing physical activities that cause the skin to get wet or sweat)
- Less likely to cause a stinging sensation or irritation on the skin, making it better for sensitive, easily-reactive skin types
- Better for those with heat-activated skin (like those prone to rosacea and extreme redness) since it deflects the heat given off by the sun along with UV rays
- Less likely to be pore-clogging, making it ideal for blemish-prone skin types (of course, this will also depend on the other ingredients used in a formula)
- Has a longer shelf life than chemical sunscreen
Physical Sunscreen Cons:
- Can rub, sweat, or rinse off easily, meaning more frequent reapplication is needed when outdoors
- May leave a white-ish cast on the skin, making some formulas incompatible with darker skin tones
- May create an occlusive film (barrier), which results in increased perspiration during physical activities. This can cause the sunscreen to wear off more quickly
- Tends to be thicker, which will require more effort to rub in
- Won’t offer full protection unless applied generously and accurately. Otherwise, UV light can get through gaps in the sunscreen molecules and penetrate the skin
Chemical Sunscreen Pros:
- Tends to be thinner and, therefore, spreads more easily on the skin, making it more wearable for daily use
- Less is needed to protect the skin because there is no risk of there being gaps between the sunscreen molecules after application
Chemical Sunscreen Cons:
- Can possibly cause an increase in existing brown spots and discoloration due to the chemical reaction that increases internal skin temperature (yes, heat can make brown spots worse)
- Requires 10-15 minutes to become effective after application
- Increased chance of irritation and stinging (especially for those who have dry skin with a damaged skin barrier) due to the multiple ingredients combined in order to achieve broad-spectrum UVA and UVB protection
- The higher the SPF (especially formulas of SPF 50 or greater), the higher the risk of irritation for sensitive skin types
- The protection it offers gets used up more quickly when in direct UV light, so reapplication must be more frequent
- Increased chance of redness for rosacea-prone skin types because it changes UV rays into heat, which can exacerbate flushing
- The chemical ingredients oxybenzone and octinoxate have been banned in Hawaii for posing a risk to coral reefs when worn while swimming in the ocean. NOTE: This applies to water-resistant beach sunscreens only and not daily use sunscreens or makeup with sunscreen.
- Can cause stinging if it drips into the eyes from sweating
The best SPF is the one you will apply regularly and is compatible with your skin type. There are Pros and Cons to both chemical and physical SPFs but the one you will apply and reapply is the best choice for you.
Join me soon for part 2 of my series and learn what SPF is best!