Understanding Chemical & Physical SPF (Plus My Top Picks)
Welcome to summer. Now, more than ever, the use of SPF is crucial to your skin health. I advocate for sunscreen year round, but I realize that not everyone feels as strongly about UVA/UVB rays as I do. There is also a tremendous amount of confusion as to whether or not we should use chemical or physical sunscreens. Don’t worry, I am going to share my favorite SPF’s, why they are great choices, the difference between chemical and physical, and how best to apply your given protectant. Welcome to The Deep Dive, SPF 2019 Edition.
First up, let’s clear up some things…
SPF means Sun Protection Factor. This relates to the ability for the product to protect the skin against the suns Ultra Violet A (UVA) rays and Ultra Violet B (UVB) rays.
The most damaging to the skin is the UVA rays due to the fact that the rays penetrate deeper than the epidermis (surface level of the skin) and go down into the dermis of the skin (the deepest level). The UVB rays only reach the epidermis.
Chemical SPF is a form of sunscreen that IS absorbed by the skin cells and converts the both types of UV rays into heat inside the body. Both rays, once converted, get released from the body. Compare this to the serum in your skincare routine, you press it into the skin and it is absorbed. Depending on the type of serum, you will feel the benefits on your skin quickly. With chemical SPF you tend to feel the heat radiate from your face. This formula is good for normal, combination, dry, and oily skin.
Physical SPF is a form of sunscreen that will sit on top of the skin and DOES NOT get absorbed into the skin and enter the bloodstream. Because the ingredients in a physical SPF will not go into the body, it will reflect off the UV rays. Think of it like your highlighter, the sun hits it, and all we see is a blinding ray of glow. This is best for sensitive skin.
(Ed. note, I have Dehydrated/Dry skin that is sensitive and have reacted with both formulas. Similarly, there are ones from both type that do not upset my skin.)
A lot of people are afraid of chemical SPF’s due to the fact that the ingredients are taken into the body and can potentially be harmful. This year, 2019, the FDA issued a statement about this. A study was released in May 2019 in the Journal of the American Medical Association, scientist MK Matta and his team found that absorption rates of chemical ingredients are not enough to cause damage. The FDA took this article and stated that they do not agree or disagree with the claims about the chemical absorption not being harmful; instead they want more tests to be done to corroborate these claims. There are 12 active ingredients in SPF, but the common actives (in order of “toxicity”) are: Oxibenzone, Octinoxate, Homosalate, Octisalate, Octocrylene, Titanium Dioxide, Zinc Oxcide, Avobenzone, Mexoryl SX.
My Personal SPF Experience…
I do not like using strictly chemical sunscreens. I tend to migrate towards a dual SPF (meaning it has chemical and physical active ingredients) daily or just physical when I am particularly sensitive. Do the fact that SPF is a DAILY NECESSITY; you need to be diligent to pick a formula and brand that is best for you. Some of my favorite brands include: Coola, Supergoop, and EltaMD. Also, the appropriate amount of sunscreen for your face need to get the complete protection of the SPF is a full teaspoon. In fact, if we are talking about SPF, a shot glass is the amount you need for your whole body. You should go through your daily SPF bottle roughly every three weeks.
The EltaMD UV Clear Broad Spectrum SPF 46 is one of my top choices. This formula is a dual SPF and has the actives of Zinc Oxide at 9% (physical) and Oxtinoxate 7.5% (chemical). The reason that I love this formula is because it applies clear and does not create any type of cast on the skin. Furthermore, it has an SPF score of 46, which means that, theoretically, your skin will go 46 times longer without burning that the 20 minute average it takes for skin to burn. I cannot attest to this as I reapply my sunscreen every 3-4 hours on days without makeup.
The UV Clear has a lot of ingredients that are great for acne prone skin.
Niacinamide is an ingredient that will help brighten any sort of PIE (the red spots after acne) and PIH (the brown spots after acne). Vitamin E (antioxidant) will be an amazing hydrator and protector of the skin. Sodium Hyaluronate (humectant) will also help to hydrate the skin as well as help heal any wounds you experience from your acne.
There are a few ingredients in this SPF that you want to watch out for. Cyclopentasiloxane (solvent) is a silicone and can clog pores. Lactic Acid (exfoliant and skin conditioner) while amazing for anti-aging and skin cell turn over, can cause irritation for sensitive skin. Butylene Glycol (humectant) is an organic alcohol that is great for conditioning the skin but can be slightly pore clogging.
A few specific SPF’s that I have used and enjoy are the EltaMD UV Physical Broad-Spectrum SPF 41 (physical), Supergoop Everyday Sunscreen Broad-Spectrum SPF 30 (chemical), Coola Mineral Face SPF 30 (physical), and the Josie Maran Argan Daily Moisturizer SPF 47 (physical).
So, what are your sunscreen preferences? Do you have a better understanding of chemical vs physical SPF?
* Both EltaMD sunscreen’s are press samples from Base Beauty Creative Agency. I have previously used the UV Clear Broad Spectrum SPF 46. *
* NONE of the links in this post are affiliate *