The difference between sunscreen and sunblock

You squirt, scoop, rub, slather your entire body. 

You play, you swim, you sweat, you hike. 

You reapply. 

You repeat. 

Basically, to get the job done right, you should be using a lot of your go-to sun protection. As a product that gets used so darn much, why is there still so much mystery and unknown about the nitty gritty of sunblocks and sunscreens. And yes -  there is an important difference between sunscreen and sunblock! Up until last year, it had been decades since the FDA proposed new regulations on the marketing and formulation efforts of the sun protection industry.

So let’s dive into the need-to-know lingo that will help you keep your skin safe from the sun. Because even though we idolize the sun in all its glory - we are after all, a skincare line that cares about your healthy skin. And to properly take care of your skin in the sun, you need to know the difference between sunscreen and sunblock.

Difference between sunscreen and sunblock

Sunscreen = This category allows the UV rays to penetrate the skin, but then the use of chemical filters alter the rays into non-damaging wavelengths. Generally rubs in clear. 

Vs

Sunblock = This category of sun protection blocks the UV rays from penetrating the skin. This makes it a physical barrier. Mineral filters are used to create this physical barrier between the sun and the skin. Sunblock often leaves a white coat on your skin rather than rubbing on clear. Though many savvy brands are adding ingredients to reduce the white cast. 

Psst - A simple trick to help you remember the difference between sunscreen and sunblock. Sunblock "blocks" UV rays from penetrating the skin. Sunscreen "screens" out damage.

There are officially 16 ingredients in use as “active ingredients” in over the counter sun protection. Let’s divide them by the two following categories, that create the difference between sunscreen and sunblock:

CHEMICAL FILTERS = Are used in sunscreens. There are 14 chemical filters currently being used in the U.S marketplace, though the FDA has found 2 to be NOT generally recognized as safe and effective (1). 

→ Trolamine Salicylate = NOT generally recognized as safe and effective.

→ PABA = Aminobenzoic acid. NOT generally recognized as safe and effective.

→ Oxybenzone = Currently under scrutiny for hormone disruption and skin allergies. It has shown a 109% absorption rate through the skin. Nearly ALL Americans, 96%, have oxybenzone in their system. It is found in breastmilk, as well.

→ Avobenzone = A study from January 2020 has shown systemic absorption of this ingredient from sunscreen application (2). The plasma concentration level was above the threshold deemed safe for use by the FDA. Not considered a hormone disruptor but has a relatively high chance of causing skin sensitivities.

→ Octinoxate = A study from January 2020 has shown systemic absorption of this ingredient from sunscreen application. The plasma concentration level was above the threshold deemed safe for use by the FDA.

→ Octisalate = A study from January 2020 has shown systemic absorption of this ingredient from sunscreen application. The plasma concentration level was above the threshold deemed safe for use by the FDA.

→ Octocrylene = A study from January 2020 has shown systemic absorption of this ingredient from sunscreen application. The plasma concentration level was above the threshold deemed safe for use by the FDA.

→ Homosalate = A study from January 2020 has shown systemic absorption of this ingredient from sunscreen application. The plasma concentration level was above the threshold deemed safe for use by the FDA.

→ Dioxybenzone = Rarely used in the U.S. Insufficient data to be considered safe or effective for use.

→ Cinoxate = Rarely used in the U.S. Insufficient data to be considered safe or effective for use.

→ Ensulizole = Rarely used in the U.S. Insufficient data to be considered safe or effective for use.

→ Mexoryl SX = Waiting FDA approval for use. Insufficient data to be considered safe or effective for use.

→ Meradimate = Rarely used in the U.S. Insufficient data to be considered safe or effective for use.

→ Padimate O = Rarely used in the U.S. Insufficient data to be considered safe or effective for use.

VS

MINERAL FILTERS = Are what is used in sunblock. There are two types and the FDA has decided that the cosmetic industry has enough information about both to deem them “generally recognized as safe and effective:”

☀ Zinc Oxide = Is considered a broad spectrum filter and can be used in concentrations of up to 25%. According to EWG the safety rating is a 2 out of their 1-10 scale. Zinc oxide is generally in powder form, and inhaling the product can be dangerous (hence the 2), though it is likely the consumer gets the product in a non powder form, making it very safe and effective to use. There is less than .01% absorption through the skin. Non-nano zinc-oxide means the particle size of the zinc oxide is large enough to not be absorbed through the skin, making it the safest, and also causing a white coat to appear on the skin (3). 

☀ Titanium Dioxide = can be used in concentrations of up to 25% and has a rating of 2 on the EWG safety scale. There is no known potential for hormone disruption. The skin does not absorb it. 

 Inactive ingredients to avoid:

→  Methylisothiazolinone = A preservative banned in europe but still found in many cosmetics in the U.S, such as sunscreens and baby wipes. Found to be a skin sensitizer or allergen in studies.

→  Retinyl palmitate = Vitamin A. Used in the cosmetic industry as an antioxidant that combats skin from signs of aging. However, with over use, and particularly with topical use before sun exposure, it may contribute to the development of skin tumors and lesions. Recommended to NOT use a sunscreen with this ingredient. 

UVA = Ultraviolet A. These long-wave rays cause the skin to prematurely age. Overexposure may eventually lead to skin cancer.

VS

UVB = Ultraviolet B. These short-wave rays cause sunburns. Overexposure may eventually lead to skin cancer.

SPF = Sun Protective Factor against UVB rays. The number indicates how much longer one can stay out in the sun before burning. For example, SPF 20, implies you can stay out 20 times longer than without sunscreen. Of course, this will vary depending on skin type, time of day, and location. In general, SPF 15 filters 92% of rays, and SPF50 filters 98%. Any higher than SPF50 is deemed negligible and can actually cause people to be overconfident in their protection and not reapply as often as necessary. 

Vs

Broad Spectrum  = Effective protection against both UVA and UVB sun rays. Both can cause damage to the skin and potentially lead to cancer.

Vs

UPF = Ultraviolet Protection Factor. Refers to how much sun penetrates through clothing. Similarly to SPF, the UPF is measured by a number. UPF50, for example, indicates that only 1/50 of the rays can make it through the piece of fabric.

What you need to know about reef safe sunblock:

Sunblocks, because they use non nano zinc oxide, or titanium dioxide, are considered a sure bet for reef-safe sun protection. Many companies use greenwashing techniques, and claim that their sunscreens are reef safe - even when they contain ingredients like oxybenzone that are linked to coral bleaching! Learn what greenwashing is here.

So what does Anato do with this information? 

We've formulated a sunblock that contains the active ingredient non-nano zinc oxide to give your face SPF 50 protection. Our 'Ocean Friendly Sunblocks' is also reef safe, waterproof for up to 2 hours, does not sting the eyes, AND it does not leave a white cast. Bonus: our sunblock doubles up as concealer for certain skin types! 

Other important ways to protect your skin from the sun:

☼ Wear protective clothes

☼ Wear hats & sunglasses

☼ Minimize prolonged sun exposure during peak hours (generally between 10am-4pm depending where you live)

EAT your Sunblock!

  To wrap it up:  

Knowing the difference between sunscreen and sunblock will allow you to make the best decisions for your health. We believe that the safest and most effective sun protection is with a broad-spectrum mineral filter sunblock. Think non-nano zinc oxide, or titanium dioxide. Sunblock will not actually be absorbed into your system, and thus will not have any unintended harm. Always use other measures to protect yourself from the sun's damaging rays, like wearing a hat, sunglasses, and eating the right foods that help your body to defend itself from sun damage. 

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